Renishaw plc RMP400 Radio Machine Probe User Manual
Renishaw plc Radio Machine Probe
User Manual

RMP400 high accuracy radio machine 
probe
Installation guide
H-6570-8501-01-A
Draft 5 16/04/18
Renishaw part no: H-6570-8501-01-A
Issued:  ??.????
© 2018 Renishaw plc. All rights reserved. 
This document may not be copied or reproduced 
in whole or in part, or transferred to any other 
media or language, by any means, without the 
prior written permission of Renishaw plc.
The publication of material within this document 
does not imply freedom from the patent rights of 
Renishaw plc.
Draft 5 16/04/18

i
Contents
Before you begin .............................................................1.1
Before you begin ............................................................1.1
Disclaimer  ..............................................................1.1
Trade marks .............................................................1.1
Warranty ................................................................1.1
Changes to equipment .....................................................1.1
CNC machines ...........................................................1.1
Care of the probe .........................................................1.1
Patents .................................................................1.2
EU declaration of conformity ...................................................1.3
FCC Information to user (USA only) .............................................1.3
WEEE directive .............................................................1.3
Radio approval  .............................................................1.4
Safety  ....................................................................1.5
RMP400 basics ...............................................................2.1
Introduction ................................................................2.1
Getting started ...........................................................2.1
System interface ..........................................................2.2
Trigger Logic™ ...........................................................2.2
Probe modes ...............................................................2.2
Configurable settings .........................................................2.2
Switch-on/switch-off methods ................................................2.2
Enhanced trigger filter  .....................................................2.4
Auto-reset function ........................................................2.4
Multiple probe mode ....................................................... 2.4
Acquisition mode .........................................................2.5
RMP400 dimensions .........................................................2.6
RMP400 specification ........................................................2.7
Recommended styli .......................................................... 2.9
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RMP400 installation guide
ii
Contents
System installation ...........................................................3.1
Installing the RMP400 with an RMI or RMI-Q ......................................3.1
Operating envelope  .......................................................3.1
Positioning the RMP400 and RMI or RMI-Q  ....................................3.2
Performance envelope .....................................................3.2
Preparing the RMP400 for use .................................................3.3
Fitting the stylus ..........................................................3.3
Installing the batteries  .....................................................3.4
Mounting the probe on a shank ..............................................3.5
Stylus on-centre adjustment ................................................. 3.6
Calibrating the RMP400  ......................................................3.7
Why calibrate a probe?  ....................................................3.7
Calibrating in a bored hole or on a turned diameter ............................... 3.7
Calibrating in a ring gauge or on a datum sphere  ................................3.7
Calibrating the probe length .................................................3.7
Trigger Logic™ ...............................................................4.1
Reviewing the probe settings  ..................................................4.1
Multiple probe mode settings  ..................................................4.2
Probe settings record  ........................................................4.3
Changing the probe settings ...................................................4.4
RMP400 – RMI partnership .................................................... 4.6
RMP400 – RMI-Q partnership .................................................. 4.7
Operating mode ............................................................. 4.8
Maintenance  .................................................................5.1
Maintenance ...............................................................5.1
Cleaning the probe ..........................................................5.1
Changing the batteries  .......................................................5.2
Fault-finding  .................................................................6.1
Parts list  .....................................................................7.1
Draft 5 16/04/18

1.1
Changes to equipment
Renishaw reserves the right to change equipment 
specifications without notice.
CNC machines
CNC machine tools must always be operated by 
fully trained personnel in accordance with the 
manufacturer’s instructions.
Care of the probe
Keep system components clean and treat the 
probe as a precision tool.
Before you begin
Before you begin Warranty
Equipment requiring attention under warranty 
must be returned to your equipment supplier. 
Unless otherwise specifically agreed in writing 
between you and Renishaw, if you purchased 
the equipment from a Renishaw company, the 
warranty provisions contained in Renishaw’s 
CONDITIONS OF SALE apply. You should consult 
these conditions in order to find out the details 
of your warranty but, in summary, the main 
exclusions from the warranty are if the equipment 
has been: 
•  neglected, mishandled or inappropriately used; 
or
•  modified or altered in any way except with the 
prior written agreement of Renishaw. 
If you purchased the equipment from any other 
supplier, you should contact them to find out what 
repairs are covered by their warranty.
Disclaimer
RENISHAW HAS MADE CONSIDERABLE 
EFFORTS TO ENSURE THE CONTENT OF THIS 
DOCUMENT IS CORRECT AT THE DATE OF 
PUBLICATION BUT MAKES NO WARRANTIES 
OR REPRESENTATIONS REGARDING 
THE CONTENT. RENISHAW EXCLUDES 
LIABILITY, HOWSOEVER ARISING, FOR ANY 
INACCURACIES IN THIS DOCUMENT.
Trade marks
RENISHAW and the probe symbol used in the 
RENISHAW logo are registered trade marks of 
Renishaw plc in the United Kingdom and other 
countries. apply innovation and names and 
designations of other Renishaw products and 
technologies are trade marks of Renishaw plc or 
its subsidiaries.
Google Play and the Google Play logo are 
trademarks of Google LLC.
Apple and the Apple logo are trademarks of 
Apple Inc., registered in the U.S. and other 
countries. App Store is a service mark of Apple 
Inc.,registered in the U.S. and other countries.
All other brand names and product names used 
in this document are trade names, trade marks, or 
registered trade marks of their respective owners.
see Section 1, “Before you begin”
Draft 5 16/04/18

1.2
Before you begin
Patents
Features of the RMP400, and other similar 
Renishaw products, are the subject of one or 
more of the following patents and/or patent 
applications:
Patents will be listed 
here when we have 
them.. Possibly all 
RMP40 patents and 
strain gauge patents 
(Steve to confirm)
Draft 5 16/04/18

1.3
Before you begin
C
FCC Information to user (USA 
only)
47 CFR Section 15.19
This device complies with part 15 of the FCC 
Rules. Operation is subject to the following two 
conditions:
1.  This device may not cause harmful 
interference, and
2.  This device must accept any interference 
received, including interference that may 
cause undesired operation.
47 CFR Section 15.21
The user is cautioned that any changes or 
modifications not expressly approved by 
Renishaw plc or authorised representative could 
void the user’s authority to operate the equipment.
EU declaration of conformity
Renishaw plc declares that the RMP400 complies 
with the applicable standards and regulations. 
Contact Renishaw plc or visit
www.renishaw.com/mtpdoc for the full EU 
declaration of conformity.
WEEE directive
The use of this symbol on Renishaw products 
and/or accompanying documentation indicates 
that the product should not be mixed with 
general household waste upon disposal. It is the 
responsibility of the end user to dispose of this 
product at a designated collection point for waste 
electrical and electronic equipment (WEEE) to 
enable reuse or recycling. Correct disposal of 
this product will help to save valuable resources 
and prevent potential negative effects on the 
environment. For more information, please contact 
your local waste disposal service or Renishaw 
distributor.
Draft 5 16/04/18

1.4
Before you begin
Radio approval
Will be listed here, when there are some (testing 
to take place first).
Draft 5 16/04/18

1.5
Before you begin
Safety
Information to the user
The RMP400 is supplied with two non-
rechargeable ½AA lithium-thionyl chloride 
batteries (approved to BS EN 62133:2013 
[IEC 62133:2012]). Once the charge in these 
batteries is depleted, do not attempt to recharge 
them.
The use of this symbol on the batteries, 
packaging or accompanying documents indicates 
that used batteries should not be mixed with 
general household waste. Please dispose of 
the used batteries at a designated collection 
point. This will prevent potential negative effects 
on the environment and human health which 
could otherwise arise from inappropriate waste 
handling. Please contact your local authority or 
waste disposal service concerning the separate 
collection and disposal of batteries. All lithium and 
rechargeable batteries must be fully discharged or 
protected from short circuiting prior to disposal.
Please ensure replacement batteries are of the 
correct type and are fitted in accordance with 
the instructions in this manual (see page 5.2, 
“Changing the batteries”), and as indicated on the 
product. For specific battery operating, safety and 
disposal guidelines, please refer to the battery 
manufacturer’s literature.
•  Ensure that all batteries are inserted with the 
correct polarity. 
•  Do not store batteries in direct sunlight or rain. 
•  Do not heat or dispose of batteries in a fire. 
•  Avoid forced discharge of the batteries. 
•  Do not short-circuit the batteries. 
•  Do not disassemble, pierce, deform or apply 
excessive pressure to the batteries. 
•  Do not swallow the batteries.
•  Keep the batteries out of the reach of children.
•  Do not get batteries wet.
•  If a battery is damaged, exercise caution when 
handling it.
Please ensure that you comply with international 
and national battery transport regulations when 
transporting batteries or the products.
Lithium batteries are classified as dangerous 
goods and strict controls apply to their shipment 
by air. To reduce the risk of shipment delays, if you 
need to return the products to Renishaw for any 
reason, do not return any batteries.
In all applications involving the use of machine 
tools or CMMs, eye protection is recommended.
The RMP400 has a glass window. Handle with 
care if broken to avoid injury.
Information to the machine supplier/ 
installer
It is the machine supplier’s responsibility to ensure 
that the user is made aware of any hazards 
involved in operation, including those mentioned 
in Renishaw product literature, and to ensure 
that adequate guards and safety interlocks are 
provided.
Under certain circumstances, the probe signal 
may falsely indicate a probe seated condition. Do 
not rely on probe signals to halt the movement of 
the machine.
Information to the equipment installer
All Renishaw equipment is designed to comply 
with the relevant EC and FCC regulatory 
requirements. It is the responsibility of the 
equipment installer to ensure that the following 
guidelines are adhered to, in order for the product 
to function in accordance with these regulations:
•  any interface MUST be installed in a position 
away from any potential sources of electrical 
noise, i.e. power transformers, servo drives etc;
•  all 0 V/ground connections should be 
connected to the machine “star point” (the “star 
point” is a single point return for all equipment 
ground and screen cables). This is very 
important and failure to adhere to this can 
cause a potential difference between grounds;
Draft 5 16/04/18

1.6
Before you begin
•  all screens must be connected as outlined in 
the user instructions;
•  cables must not be routed alongside high 
current sources, i.e. motor power supply cables 
etc, or be near high-speed data lines;
•  cable lengths should always be kept to a 
minimum.
Equipment operation
If this equipment is used in a manner not specified 
by the manufacturer, the protection provided by 
the equipment may be impaired.
Draft 5 16/04/18

2.1
RMP400 basics
Introduction
The RMP400 offers an unrivalled combination 
of size, accuracy, reliability and robustness 
and, allows high-accuracy probing on small to 
medium machining centres or other machines 
where line-of-sight problems affect optical signal 
transmission. 
Successfully combining patented RENGAGE™ 
strain gauge technology with the patented 
frequency hopping radio transmission system of 
the RMP40, the RMP400 provides existing probe 
users with a simple upgrade to solid-state strain 
gauge technology and all the associated benefits 
this brings: 
•  excellent 3D performance to allow probing of 
contoured surfaces;
•  improved repeatability in all probing directions;
•  a low triggering force combined with low pre-
travel variation to provide high accuracy, even 
when used with long styli;
•  a proven ten-fold improvement in life (10 million 
triggers); ????
•  the elimination of reseat failures;
•  high resistance to machine tool vibration;
•  resistance to shock and false triggering 
through the use of solid state accelerometers.
In addition to providing high-accuracy 
measurement on your machine tool, the RMP400 
also offers: 
•  Faster calibration: 
On complex 3D parts, it is common to 
measure in several different directions. Each 
direction of a standard mechanical probe must 
be calibrated, to ensure that the pre-travel 
variation is compensated in the measurement. 
Performing this calibration for every 3D 
direction can be time-consuming.
The RMP400 has almost no pre-travel 
variation, so a single calibration value may be 
used for any probing angle in 2D or 3D. This 
results in a vastly reduced calibration time. An 
additional benefit is a corresponding reduction 
in errors introduced by environmental changes 
within the machine during a long calibration 
cycle.
•  The ability to be used in applications 
where axial and radial reorientations are 
used, enabled by the use of solid state 
accelerometers:
The auto-reset function is required and 
recommendations should be followed for 
optimum metrology performance. 
Getting started
Three multicolour probe LEDs provide visual 
indication of selected probe settings.
For example:
• Switch-on and switch-off methods
• Probe status – triggered or seated
• Battery condition
Batteries are inserted or removed as shown (see 
page 3.5, “Installing the batteries”) for further 
information). 
On insertion of batteries, the LEDs will begin 
to flash (see page 4.1, “Reviewing the probe 
settings”).
see Section 2, “RMP400 basics”
Draft 5 16/04/18

2.2
RMP400 basics
System interface
The RMI and RMI-Q are integrated interfaces/
receivers used to communicate between the 
RMP400 probe and the machine control.
Trigger Logic™
Trigger Logic (see Section 4, “Trigger Logic™”) is 
a method that allows the user to view and select 
all available mode settings in order to customise 
a probe to suit a specific application. Trigger 
Logic is activated by battery insertion and uses 
a sequence of stylus deflections (triggering) to 
systematically lead the user through the available 
choices to allow selection of the required mode 
options.
A Trigger Logic app is available that simplifies this 
process with clear, interactive instructions and 
informative videos and is available for download 
on the following app stores.
or
Current probe settings can be reviewed by 
simply removing the batteries for a minimum of 
five seconds, and then replacing them to activate 
the Trigger Logic review sequence.
Probe modes
The RMP400 probe can be in one of three modes:
Standby mode – Probe is waiting for a switch-on 
signal.
NOTE: The RMP400 will enter hibernation mode 
should the system interface be powered off or 
out of range for a period of 30 seconds (only 
applicable to “radio on” mode).
Operational mode – When activated by one of 
the switch-on methods, the probe is switched on 
and ready for use.
Configuration mode – Ready to change the 
probe settings using Trigger Logic.
Configurable settings
Switch-on/switch-off methods
The following switch-on/switch-off options are 
user-configurable.
•Radio on/Radio off
•Radio on/Timer off
•Spin on/Spin off
•Spin on/Timer off
Draft 5 16/04/18

2.3
RMP400 basics
RMP400 switch-on method
Switch-on options are configurable
RMP400 switch-off method
Switch-off options are configurable
Probe ready time
Radio on
Radio switch on is commanded by 
machine input.
Radio off
Radio switch off is commanded by 
machine input. A timer automatically 
switches the probe off 90 minutes 
after the last trigger if it is not turned 
off by machine input.
Timer off (timeout)
Timeout will occur 12, 33 or 134 
seconds (user configurable) after the 
last probe trigger or reseat.
1.7 seconds 
maximum.
Spin on
Spin at 500 rev/min for one second 
minimum.
Spin off
Spin at 500 rev/min for one second 
minimum. A timer automatically 
switches the probe off 90 minutes 
after the last trigger if it is not spun.
Timer off (timeout)
Timeout will occur 12, 33 or 134 
seconds (user configurable) after the 
last probe trigger or reseat.
2.5 seconds. (The 
probe must be 
stationary for 2.5 
seconds minimum 
after it has stopped 
spinning.)
NOTES:
In “radio on” mode, the switch-on time is user 
selectable “fast” or “standard” when using 
RMI-Q (selection is made in RMI-Q). Otherwise 
1.7 seconds.
For more information on the user selectable 
switch-on time when operating with RMI-Q, please 
refer to the installation guide RMI-Q radio machine 
interface (Renishaw part no. H-5687-8504).
In “radio on” mode, the switch-on time assumes 
a good radio communication link. In a poor RF 
environment this may rise to a maximum of 
3.0 seconds.
In “spin on” mode, the one second starts from 
the moment the spindle reaches 500 rev/min.
The RMP400 must be on for a minimum of 
one second before being switched off.
Draft 5 16/04/18

RMP400 installation guide
2.4
RMP400 basics
Enhanced trigger filter
Probes subjected to high levels of vibration or 
shock loads may output signals without having 
contacted any surface. The enhanced trigger filter 
improves the probe’s resistance to these effects.
When the filter is enabled, a constant 8 ms or 
16 ms delay is introduced to the probe’s output. 
The factory setting is 8 ms. If false triggering is 
noticed, then consider increasing the filter delay to 
16 ms.
Auto-reset function
In previous strain gauge products, the probe was 
required to be turned off during reorientation 
moves. The auto-reset function in the RMP400 
can compensate for stylus forces, resulting from 
changes in probe orientation, that can cause the 
probe to trigger.
This feature is controlled by solid state 
accelerometers and is suitable for applications 
where axial and radial reorientation of the probe is 
applied. 
To achieve optimum metrology performance 
when the auto-reset function is turned on, a dwell 
is recommended before making a programmed 
move that follows any reorientation of the probe.
When using a stylus of up to 150 mm long, 
a 0.2 second dwell is necessary. In most 
applications the machine response time will 
adequately provide this.
When using a heavy stylus configuration, or a 
stylus longer than 150 mm, it is recommended 
that the RMP400 should be turned off during 
reorientation moves.
Multiple probe mode
The RMP400 can be configured, using Trigger 
Logic, to allow multiple radio probes in “spin on/
spin off” or “shank on/shank off” to be used with a 
single RMI or RMI-Q.
Up to four RMP400s can be used with a single 
RMI-Q in “radio on/radio off” mode. For further 
details of this functionality, please refer to the 
installation guide RMI-Q radio machine interface 
(Renishaw part no. H-5687-8504).
NOTES:
Multiple probe mode is a function of the RMP400, 
as such, the option will not appear when the 
“radio on” option has been selected.
RMP400 probes which are set to “multiple probe 
mode on” can coexist alongside any number of 
RMP400 probes set to “multiple probe mode off”.
To allow multiple radio probes to work in close 
proximity, and with a single RMI or RMI-Q, 
16 choices of “mode on” colours are available, 
each representing a different machine tool 
installation. (see page 4.2, “Multiple probe 
settings”).
All probes operating with a single RMI or RMI-Q 
must be set to the same “mode on” colour choice; 
any multiple probes located on adjacent machines 
must all be set to an alternative “mode on” colour 
choice.
NOTE: Each probe per “mode on” colour choice 
needs to be partnered with the RMI or RMI-Q. 
By configuring multiple probes to a single “mode 
on” colour choice, all probes using this “mode on” 
colour choice will have the same identity. 
The probe to be partnered is partnered after 
selecting the multiple probe mode setting and 
choosing the “mode on” option. (see page 4.4, 
“Changing the probe settings”).
There is no limit to the number of probes that can 
be used with a single RMI or RMI-Q so long as 
they all have the same “mode on” colour choice. 
All RMP400 probes are factory set to “mode off”.
The addition of any further probe(s) into a single 
probe installation will require that all probes are 
reconfigured to the same “mode on” colour choice 
and that one of the probes is then repartnered 
with the RMI or RMI-Q. 
Draft 5 16/04/18

2.5
RMP400 basics
The addition of any further probe(s), or 
replacements, into a multi-probe installation can 
be achieved simply through the reconfiguration of 
the probe to the same “mode on” colour choice.
Acquisition mode
System set-up is achieved using Trigger Logic and 
powering-on the RMI or RMI-Q.
Partnering is only required during initial system 
set-up. Further partnering is only required if either 
the RMP400 or RMI/RMI-Q is changed.
NOTES:
Systems using the RMI-Q can be partnered with 
up to four RMP400s manually. Alternatively this 
can be achieved by using ReniKey; a Renishaw 
machine macro cycle which does not require the 
RMI-Q to be power cycled. 
For more information or to download ReniKey free 
of charge visit: 
www.renishaw.com/mtpsupport/renikey
Partnering by ReniKey is not available for RMI.
Partnering will not be lost by reconfiguration of 
probe settings or when changing batteries, except 
where multiple probe mode is selected.
Partnering can take place anywhere within the 
operating envelope.
Draft 5 16/04/18

A range of probe-ready shanks is 
available from Renishaw
50.5 (1.99)
19 (0.75)
Battery cassette 
RMP400 window
11°
11°
Ø40 (Ø1.57)
50 (1.97)
M4 stylus
Probe status LED
2.6
RMP400 basics
RMP400 dimensions
Dimensions given in mm (in)
Stylus overtravel limits
Stylus length ±X/±Y Z
50 (1.97) 12 (0.47) 6 (0.24)
100 (3.94) 22 (0.87) 6 (0.24)
Draft 5 16/04/18

2.7
RMP400 basics
RMP400 specification
Principal application Workpiece inspection and job set-up on multi-tasking machines, 
machining centres and gantry machining centres.
Dimensions Length
Diameter
50.5 mm (1.99 in)
40 mm (1.57 in)
Weight (without shank) With batteries
Without batteries
262 g (9.24 oz)
242 g (8.54 oz)
Transmission type Frequency hopping spread spectrum (FHSS) radio
Radio frequency 2400 MHz to 2483.5 MHz
Switch-on methods Radio M-code or spin on
Switch-off methods Radio M-code, timer or spin off
Probe feedrate (minimum) 3 mm/min (0.12 in/min) (see note 6)
Spindle speed (maximum) 1000 rev/min
Operating range Up to 15 m (49.2 ft)
Receiver/interface RMI or RMI-Q combined interface and receiver unit
Sense directions ±X, ±Y, +Z
Unidirectional repeatability 0.25 µm (10 µin) 2s – 50 mm stylus length (see note 1)
0.35 µm (14 µin) 2s – 100 mm stylus length
X, Y (2D) form measurement 
deviation
±0.25 µm (10 µin) – 50 mm stylus length (see note 1)
±0.25 µm (10 µin) – 100 mm stylus length
X, Y, Z (3D) form 
measurement deviation
±1.00 µm (40 µin) – 50 mm stylus length (see note 1)
±1.75 µm (70 µin) – 100 mm stylus length
Stylus trigger force
(see notes 2 and 5)
XY plane (typical minimum)
+Z direction (typical minimum)
0.06 N, 6 gf (0.22 ozf) 
2.55 N, 260 gf (9.17 ozf)
Stylus overtravel force
XY plane (typical minimum)
+Z direction (typical minimum)
1.04 N, 106 gf (3.74 ozf) (see note 3)
5.50 N, 561 gf (19.78 ozf) (see note 4) 
Stylus overtravel XY plane
+Z plane
±11°
6 mm (0.23 in)
Note 1 Performance specification is tested at a standard test velocity of 240 mm/min (9.45 in/min) with a 50 mm (1.97 in) 
carbon fibre stylus. Significantly higher velocity is possible depending on application requirements.
Note 2 Trigger force, which is critical in some applications, is the force exerted on the component by the stylus when the 
probe triggers. The maximum force applied will occur after the trigger point (overtravel). The force value depends on 
related variables including measuring speed and machine deceleration. RENGAGE™ equipped probes offer ultra-
low trigger forces.
Note 3 Stylus overtravel force in the XY plane typically occurs 70 µm (2755.91 µin) after the trigger point and rises by 
0.1 N mm 10 gf/mm (9.1 oz/in) until the machine tool stops (in the high force direction and using a 50 mm (1.97 in) 
carbon fibre stylus).
Note 4 Stylus overtravel force in the +Z direction occurs 10 µm (393.70 µin) to 11 µm (433.07 µin) after the trigger point and 
rises by 1.2 N/mm, 122 gf/mm (109.60 oz/in) until the machine tool stops. 
Note 5 These are the factory settings, manual adjustment is not possible.
Note 6 Speeds below 3 mm/min commonly occur when manually moving the probe using the handwheel with a very fine 
feedrate.
TBC by end of March
TBC
Draft 5 16/04/18

RMP400 installation guide
2.8
RMP400 basics
Environment IP rating IPX8, BS EN 60529:1992+A2:2013 
(IEC 60529:1989+A1:1999+A2:2013)
IK rating IK01 (BS EN IEC 62262: 2002) [for glass 
window]
Storage temperature –10 °C to +70 °C (+14 °F to +158 °F)
Operating temperature +5 °C to +50 °C (+41 °F to +122 °F)
Battery types 2 × ½AA 3.6 V lithium-thionyl chloride (LTC)
Battery reserve life Approximately one week after a low battery warning is first given (based 
on 5% usage).
Typical battery life See the table below.
Typical battery life
Battery type
Spin switch on Radio switch on
Continuous use
Standby life  5% usage
(72 minutes/day)
Standby life  5% usage
(72 minutes/day)
Lithium-thionyl 
chloride 230 days 90 days 230 days 90 days 165 hours
NOTE:  Using RMP400 with “fast radio on” mode will result in a 20% reduction in standby battery life 
and a 10% reduction in 5% usage battery life.
Draft 5 16/04/18

2.9
RMP400 basics
A
D
C
B
Recommended styli
High modulus carbon fibre styli are designed to 
minimise pre-travel and improve accuracy, as 
the stem material is extremely stiff. This inherent 
stiffness makes the following styli most suitable for 
strain gauge applications.
Part number A-5003-7306
Carbon fibre
A-5003-6510
Carbon fibre
A-5003-6511
Carbon fibre
A-5003-6512
Carbon fibre
ABall diameter mm (inch) 6 (0.24) 6 (0.24) 6 (0.24) 6 (0.24)
BLength mm (inch) 50 (1.97) 100 (3.94) 150 (5.91) 200 (7.88)
CStem diameter mm (inch) 4.5 (0.18) 4.5 (0.18) 4.5 (0.18) 4.5 (0.18)
DEWL mm (inch) 38.5 (1.52) 88.5 (3.48) 138.5 (5.45) 188.5 (7.42)
Mass in g (oz) 4.1 (0.14) 6.2 (0.22) 7.5 (0.26) 8.7 (0.31)
The featured range of solid carbon fibre styli 
ensure the best possible performance of the 
RMP400.
It is possible that the featured range of solid 
carbon fibre styli may not be suitable for every 
RMP400 application and that it may be necessary 
to select specialised styli configurations to meet 
specific application requirements.
In applications where specialised styli are to be 
used, it may be beneficial to reduce the speed of 
probing moves. It has been seen in some cases 
that specialist styli configurations do not exhibit 
the probing characteristics and performance 
that would have otherwise been expected and 
achieved when using standard styli. Reducing the 
speed of the probing move may, in some cases, 
improve the performance of the probe.
When selecting components for an application 
specific stylus, it is recommended that 
a configuration with the least number of 
components is chosen. The stylus diameter 
should always be as large as possible and the 
overall stylus length kept to a minimum. If a stem 
with a reduced diameter is required, then it is 
recommended that an M4 stem with a short length 
and reduced diameter is selected.
Draft 5 16/04/18

2.10
RMP400 basics
This page is intentionally left blank.
Draft 5 16/04/18

3.1
System installation
see Section 3, “System installation”
Installing the RMP400 with an RMI or RMI-Q
CNC machining 
centre spindle
RMP400 
inspection probe
RMI or RMI-Q 
interface Mounting 
bracket
CNC 
machine 
control
Interface unit
Typical tool 
setting probe Cable
Workpiece
Stylus
Operating envelope
Radio transmission does not require line-of-sight 
between the probe and interface as it works 
via reflected paths, and will pass through gaps 
and machine tool windows. This allows easy 
installation, either inside or outside the machine 
enclosure, as long as the probe and RMI or 
RMI-Q are kept within the performance envelope 
shown overleaf. 
Coolant and swarf residue accumulating on 
the RMP400 and RMI or RMI-Q may have a 
detrimental effect on transmission performance. 
Wipe clean as often as is necessary to maintain 
unrestricted transmission.
When operating, do not cover the probe glass 
window, RMI or RMI-Q with your hands, as this 
will affect the performance.
Draft 5 16/04/18

3.2
System 
installation
Positioning the RMP400 and RMI or 
RMI-Q
The probe system should be positioned so that 
the optimum range can be achieved over the full 
travel of the machine’s axes. Always face the front 
cover of the RMI or RMI-Q in the general direction 
of the machining area and the tool magazine, 
ensuring both are within the performance 
envelope shown below. To assist in finding the 
optimum position of the RMI or RMI-Q, the signal 
quality is displayed on an RMI or RMI-Q signal 
LED.
NOTE: Installing the RMP400 and RMI or RMI-Q 
with the RMP400 in radio-on configuration
The RMP400 has a built-in hibernation mode 
(battery-saving mode) that saves battery life 
when the RMI or RMI-Q is unpowered in radio-on 
(radio-off or timer-off) configurations. The RMP400 
goes into hibernation mode 30 seconds after 
the RMI or RMI-Q is unpowered (or the RMP400 
is out of range). When in hibernation mode, the 
RMP400 checks for a powered RMI or RMI-Q 
every 30 seconds. If found, the RMP400 goes 
from hibernation mode to standby mode, ready for 
radio-on.
Performance envelope
The RMP400 and RMI or RMI-Q must be within 
each other’s performance envelope, as shown 
below. The performance envelope shows line-of-
sight performance, however, this is not necessary 
for the RMP400 radio transmission as it will 
operate with any reflected radio path provided 
that the reflected path length does not exceed the 
15 m (49.2 ft) operating range.
Typical plot at +20 °C (+68 °F) 
Transmission range in m (ft) 
Performance envelope when using the RMP400 with the RMI or RMI-Q
75°
60°
45°
30°
15°
0°
15°
30°
45°
60°
75° 90° 75°
60°
45°
30°
15°
0°
15°
45°
60°
75°
75°
60°
45°
30°
30°
45°
60° 75°
10 (33)
15 (49)
15°
0°
15°
30°
5 (16)
10 (33)
15 (49)
Operating and switch-on / switch-off
5 (16)
Draft 5 16/04/18

1
2
3.3
System 
installation
Preparing the RMP400 for use
Fitting the stylus
M-5000-3707
1.8 Nm – 2.2 Nm
(1.3 lbf.ft – 1.6 lbf.ft) 
Draft 5 16/04/18

3.4
System 
installation
Installing the batteries
NOTES:
See (Section 5,“Maintenance”)for a list of suitable 
battery types.
If dead batteries are inadvertently inserted, the 
LEDs will remain a constant red.
Do not allow coolant or debris to enter the battery 
compartment. When inserting batteries, check that 
the battery polarity is correct.
After the batteries have been inserted, the LEDs 
will display the current probe settings, for details, 
(see Section 4, “Trigger Logic™”).
1
4
Please remove the 
battery isolation device 
from the battery 
compartment before use.
2
3
Draft 5 16/04/18

3.5
System 
installation
Mounting the probe on a shank
2 mm A/F 
× 2
2 mm A/F 
× 4
× 4
× 2
2 mm A/F 
× 2
0.5 Nm – 1.5 Nm 
(0.4 lbf.ft – 1.1 lbf.ft)
1
2
Draft 5 16/04/18

1
23
±2.5 µm
±10 µm
±10 µm
3.6
System 
installation
Stylus on-centre adjustment
1.5 Nm – 2.2 Nm
(1.1 lbf.ft – 1.6 lbf.ft)
1.5 Nm – 2.2 Nm
(1.1 lbf.ft – 1.6 lbf.ft)
NOTES:
If a probe and shank assembly is dropped, it must 
be rechecked for correct on-centre adjustment.
Do not hit or tap the probe to achieve on-centre 
adjustment.
× 4
× 2
× 4
360°
360°
360°
Draft 5 16/04/18

3.7
System 
installation
Calibrating the RMP400
Why calibrate a probe?
A spindle probe is just one component of the 
measurement system which communicates with 
the machine tool. Each part of the system can 
introduce a constant difference between the 
position that the stylus touches and the position 
that is reported to the machine. If the probe is 
not calibrated, this difference will appear as an 
inaccuracy in the measurement. Calibration of the 
probe allows the probing software to compensate 
for this difference.
During normal use, the difference between the 
touch position and the reported position does 
not change, but it is important that the probe is 
calibrated in the following circumstances:
•when a probe system is to be used for the first
time;
•when the enhanced trigger filter delay is
changed;
•when a new stylus is fitted to the probe;
•when it is suspected that the stylus has
become distorted or that the probe has been
crashed;
•at regular intervals to compensate for
mechanical changes of your machine tool;
•if repeatability of relocation of the probe shank
is poor. In this case, the probe may need to be
recalibrated each time it is selected.
It is good practice to set the tip of the stylus on-
centre, because this reduces the effect of any 
variation in spindle and tool orientation (see page 
3.6, “Stylus on-centre adjustment”). A small 
amount of run-out is acceptable, and can be 
compensated for as part of the normal calibration 
process.
Three different operations are to be used when 
calibrating a probe. They are:
•calibrating either in a bored hole or on a turned
diameter of known position;
•calibrating either in a ring gauge or on a datum
sphere;
•calibrating the probe length.
Calibrating in a bored hole or on a 
turned diameter
Calibrating a probe, either in a bored hole or on 
a turned diameter of known size, automatically 
stores values for the offset of the stylus ball to 
the spindle centre line. The stored values are 
then used automatically in the measuring cycles. 
Measured values are compensated by these 
values so that they are relative to the true spindle 
centre line.
Calibrating in a ring gauge or on a 
datum sphere
Calibrating a probe either in a ring gauge or 
on a datum sphere with a known diameter 
automatically stores one or more value for the 
radius of the stylus ball. The stored values are 
then used automatically by the measuring cycles 
to give the true size of the feature. The values are 
also used to give true positions of single surface 
features.
NOTE: The stored radius values are based on the 
true electronic trigger points. These values are 
different from the physical sizes.
Calibrating the probe length
Calibrating a probe on a known reference surface 
determines the length of the probe, based on 
the electronic trigger point. The stored value for 
length is different from the physical length of the 
probe assembly. Additionally, the operation can 
automatically compensate for machine and fixture 
height errors by adjusting the probe length value 
that is stored.
Draft 5 16/04/18

3.8
System 
installation
This page is intentionally left blank.
Draft 5 16/04/18

4.1
Key to the symbols
LED short flash
LED long flash
Switch-on method
Radio on
(omitted if “multiple probe mode” is selected) or
Spin on
Switch-off method
Radio off or 
Spin off or
Short timeout
12 s or
Medium timeout
33 s or
Long timeout
134 s
LED check
Probe in standby mode (after 5 seconds)
Enhanced trigger filter and auto-reset facility
Auto-reset off
Trigger filter 
on 8 ms or
Auto-reset off
Trigger filter 
on 16 ms or
Auto-reset on
Trigger filter 
on 8 ms or
Auto-reset on
Trigger filter 
on 16 ms or
Auto-reset off
Trigger filter 
off
Battery status
Battery good or Battery low
Multiple probe mode (omitted for “radio on”)
see “Multiple probe mode settings” to view all 16 choices
Mode off Mode on
or Machine 1 or Machine 2 or or Machine 16
Reviewing the probe settings
Trigger Logic™
see Section 4, “Trigger Logic™”
Hibernation mode (only for “radio on”)
On
30 s or
On
5 s or Off
1
> 5 s
2
3
Draft 5 16/04/18

RMP400 installation guide
4.2
Trigger Logic
Multiple probe mode settings
Deflect the stylus for less than 4 seconds to cycle 
to the next setting.
Multiple probe mode
Mode off Mode on
or Machine 1 or Machine 2 or Machine 3 or Machine 4
Machine 5 or Machine 6 or Machine 7 or Machine 8
Machine 9 or Machine 10 or Machine 11 or Machine 12
Machine 13 or Machine 14 or Machine 15 or Machine 16
Return to
“Mode off”
Draft 5 16/04/18

4.3
Trigger Logic
Factory 
settings
New 
settings
Switch-on method Radio on         
Spin on        
Switch-off method Radio or spin         
Short timeout (12 s)        
Medium timeout (33 s)        
Long timeout (134 s)        
Auto-reset and 
enhanced trigger filter
Auto reset off / 
Trigger filter on (8 ms)
Auto reset off / 
Trigger filter on (16 ms)
Auto reset on / 
Trigger filter on (8 ms)
        
Auto reset on / 
Trigger filter on (16 ms)
Auto reset off / Trigger filter off        
Hibernation mode On (30 s)         
On (5 s)        
Off        
Multiple probe mode Off (factory set)         
On (machine number)  See “Multiple 
probe settings”
RMP400 serial no ........................................
 tick
Probe settings record
This page is provided to note your probe’s 
settings.  tick
Factory settings are for kit (A-6570-0001) only.
Draft 5 16/04/18

RMP400 installation guide
4.4
Trigger Logic
LED check
1
> 5 s
2
3
Probe partnering function
The probe partnering function enables the 
RMP400 to be partnered with the RMI or RMI-Q 
independently of the configuration process for 
other probe settings. To partner RMP400 with 
RMI or RMI-Q, insert the batteries or, if they 
have already been installed, remove them for five 
seconds and then refit them.
Following an LED check, the RMP400 will 
proceed to show the probe settings, this will end 
with “Probe status” being displayed. If the battery 
power is good, probe status will be eight green 
flashes. If battery power is low, each green flash 
will be followed by a blue flash.
Key to the symbols
LED short flash
LED long flash
Deflect the stylus for less than 4 seconds 
to move to the next menu option.
To exit, leave the stylus untouched for 
more than 120 seconds.
Acquisition successful. Probe is now in 
standby.
Whilst the “Probe status” is being displayed, 
deflect and immediately release the stylus  to 
enter “Acquisition mode”.
“Acquisition mode off” will be displayed as a 
sequence of light blue flashes, at this point the 
RMI or RMI-Q must be turned on. 
On the RMP400 select “Acquisition mode on” 
by deflecting the stylus for less than 4 seconds. 
After a successful acquisition, the RMP400 will 
timeout after 8 seconds and then go into standby. 
If “Acquisition mode on” is not selected, the 
RMP400 will timeout after 120 seconds and then 
go into standby (see page 4.10, “RMP400 – RMI 
partnership”) or (see page 4.11, “RMP400 – 
RMI-Q partnership”).
Probe status (seated)
Battery good or Battery low
Probe status
Battery good
or
Battery low
Whilst the “Probe status” is being displayed, 
deflect and release the stylus to enter 
“Acquisition mode off”. Probe status will flash 
red to acknowledge this.
At this point turn on either the RMI or RMI-Q.
All probe settings will be shown, ending 
with “Probe status” being displayed.
Draft 5 16/04/18

4.5
Trigger Logic
Acquisition mode
Acquisition mode off Acquisition mode on
8 seconds
probe in standby
120 seconds 
probe in standby
After 8 
seconds
If acquisition is unsuccessful “Acquisition mode off” will be 
displayed again after 8 seconds. 
Deflect the stylus for less than 4 seconds to select “Acquisition 
mode on” again.
Acquisition 
successful 
Draft 5 16/04/18

RMP400 installation guide
4.6
Trigger Logic
Key to the symbols
LED short flash
LED long flash
Deflect the stylus for less than 4 seconds 
to move to the next menu option.
Deflect the stylus for more than 
4 seconds to move to the next menu.
To exit, leave the stylus untouched for 
more than 120 seconds.
To exit, leave the stylus untouched for 
more than 20 seconds.
LED check
Probe status (triggered)
Battery good or Battery low
Changing the probe settings
Insert the batteries or, if they have already been 
installed, remove them for five seconds and then 
refit them.
Following the LED check, immediately deflect the 
stylus and hold it deflected until eight red flashes 
have been observed (if the battery power is low, 
each red flash will be followed by a blue flash).
Keep the stylus deflected until the “Switch-on 
method” setting is displayed, then release it.
CAUTION: Do not remove the batteries whilst 
in configuration mode. To exit, leave the stylus 
untouched for more than 20 seconds.
Switch-off method
Radio off or 
Spin off
Short 
timeout
12 s
Medium 
timeout
33 s
Long 
timeout
134 s
Switch-on method
(omitted if “multiple probe mode” was selected)
Radio on Spin on
Enhanced trigger filter setting and auto-reset facility
Auto reset off
Trigger filter 
on 8 ms
Auto reset off
Trigger filter 
on 16 ms
Auto reset on 
Trigger filter 
on 8 ms
Auto reset on
Trigger filter 
on 16 ms
Auto reset off
Trigger filter 
off
> 5 s
12
3
Draft 5 16/04/18

4.7
Trigger Logic
Stop triggering here, unless “Multiple probe 
mode” is required, in which case deflect the 
stylus for more than 4 seconds.
New settings 
complete, 
probe in 
standby
If no changes are made in “Multiple probe mode”, then deflecting the 
stylus for more than 4 seconds will return the probe settings to beginning 
of the Trigger Logic menu. If “Multiple probe mode” is selected, proceed to 
“Acquisition mode” to repartner one probe with the RMI-Q.
Return to the beginning of the Trigger Logic menu
Multiple probe mode (omitted for “radio on”)
(see “Multiple probe mode settings” to view all 16 choices)
Mode off Mode on
Machine 1 Machine 2
Machine 16
Hibernation mode (only for “radio on”)
On
30 s
On
5 s
Off
NOTE: Further probes used require the same 
“Multiple probe mode” setting, but do not need 
to be partnered with the RMI or RMI-Q.
NOTE: If using “Multiple probe mode”, refer 
to the installation guide RMI radio machine 
interface (Renishaw part no. H-4113-8554) or the 
installation guide RMI-Q radio machine interface 
(Renishaw part no. H-5687-8504).
NOTE: To partner an RMP400 with an RMI-Q 
please see “RMP400 – RMI-Q partnership”. Once 
acquisition has been successful, the RMP400 will 
revert to “Acquisition mode off”.
NOTE: To partner an RMP400 with an RMI 
please see “RMP400 – RMI partnership”. Once 
acquisition has been successful, the RMP400 will 
revert to “Acquisition mode off”.
Acquisition mode
Acquisition mode off Acquisition mode on
Acquisition mode
Acquisition mode off Acquisition mode on
120 seconds 
probe in standby
120 seconds 
probe in standby
Draft 5 16/04/18

RMP400 installation guide
4.8
Trigger Logic
Master reset function
RMP400 features a master reset function to assist 
user’s who have mistakenly changed the probe 
settings into an unintended state.
The application of the master reset function will 
clear all current probe settings and return the 
probe to default settings.
The default settings are as follows:
• Radio switch-on
• Radio switch-off
• Auto-reset on, Enhanced trigger filter on 8 ms
• Hibernation mode on 30 s
• Multiple probe mode off
The default settings may not be representative of 
the required probe settings. Further configuration 
of RMP400 may subsequently be necessary to 
achieve the required probe settings.
To reset the probe
1.  First enter into the Trigger Logic™ menu and 
ensure that the stylus is no longer deflected.
2.  From within the Trigger Logic menu, hold the 
stylus deflected for 20 seconds. After this 
the status LEDs will proceed to flash yellow 
eight times. A confirmation for master reset 
is required, if nothing is done the probe will 
timeout.
To confirm that a master reset is required, 
release the stylus and then hold the stylus 
deflected again until the eight yellow flash 
sequence has ended. This action will clear 
all probe settings and return the probe to 
default settings. Following an LED check the 
RMP400 will then go back into Trigger Logic 
and will display “Switch-on method”.
3.  Further configuration using Trigger Logic may 
be necessary to achieve the required probe 
settings.
1.  Probe is in the Trigger Logic menu. 
Ensure that the stylus is no longer deflected.
Whilst the status LEDs are flashing yellow to confirm that 
a master reset is required, release the stylus and then 
hold the stylus deflected again until the eight yellow flash 
sequence has ended.
System status LED
Deflect the stylus for 20 seconds until the 
status LEDs start to flash yellow eight times.
2.
Previous settings have been cleared. 
The probe now has default settings.
Draft 5 16/04/18

4.9
Trigger Logic
LED check
Switch-on method
Probe is now back in the Trigger 
Logic menu and will display 
“Switch-on method”.
Configure probe settings as required 
using Trigger Logic
3.
NOTE: RMP400 will continue to be partnered with either the RMI or RMI-Q following the 
activation of the master reset function, unless “Multiple probe mode” has been used.
Draft 5 16/04/18

4.10
Trigger Logic
RMP400 – RMI partnership
System set-up is achieved using Trigger Logic 
and powering the RMI. Partnering is only required 
during initial system set-up. Further partnering 
will be required if either the RMP400 or RMI 
is changed, or if a system is reconfigured for 
multiple probes (multiple probe mode).
Deflect the stylus to select “Acquisition 
mode on”. Ensure this is done within 
8 seconds of the RMI signal LED 
flashing green.
The probe is now in standby 
and the system is ready for use.
Partnering will not be lost by reconfiguring the 
probe settings or when changing batteries, except 
where multiple probe mode is selected. Partnering 
can take place anywhere within the operating 
envelope.
In configuration mode, configure the probe 
settings as required until you reach the 
“Acquisition mode” menu, which defaults to 
“Acquisition mode off”.
SIGNAL LED
RMI in acquisition mode
SIGNAL LED
New partner RMP acquired
Acquisition mode
Acquisition mode off
Switch the RMI on
NOTE: Please refer to the 
installation guide RMI radio 
machine interface (Renishaw part 
no. H-4113-8554) when partnering 
the RMP400.
> 20 s
Draft 5 16/04/18

4.11
Trigger Logic
RMP400 – RMI-Q partnership
System set-up is achieved by using Trigger Logic 
and powering on the RMI-Q or applying ReniKey. 
Partnering is required during initial system set-up. 
Further partnering will be required if either the 
RMP400 or RMI-Q is changed.
Partnering will not be lost by reconfiguring 
the probe settings or changing the batteries. 
Partnering can take place anywhere within the 
operating envelope.
Deflect the stylus to select “Acquisition 
mode on”. Ensure this is done within 60 
seconds of the RMI-Q system status 
LED flashing green.
The probe is now in standby 
and the system is ready for use.
An RMP400 that is partnered with the RMI-Q 
but then used with another system will need to 
be repartnered before being used again with the 
RMI-Q.
In configuration mode, configure the probe 
settings as required until you reach the 
“Acquisition mode” menu, which defaults to 
“Acquisition mode off”.
SYSTEM STATUS LED
RMI-Q in acquisition mode 
with empty probe location
SYSTEM STATUS LED
New partner RMP acquired
Acquisition mode
Acquisition mode off
Switch the RMI-Q on
SYSTEM STATUS LED
RMI-Q in acquisition mode 
with full probe location
or
SYSTEM STATUS LED
Acquisition pending
or
SYSTEM STATUS LED
RMP cleared from location
Displayed for 5 seconds
NOTE: Please refer to the 
installation guide RMI-Q radio 
machine interface (Renishaw part 
no. H-5687-8504) when partnering 
up to four RMPs.
 
> 20 s
Draft 5 16/04/18

4.12
Trigger Logic
Operating mode
NOTE: Due to the nature of lithium-thionyl 
chloride batteries, if a “low battery” LED warning is 
ignored, it is possible for the following sequence of 
events to occur:
1. When the probe is active, the batteries
discharge until battery power becomes too
low for the probe to operate correctly.
2. The probe stops functioning, but then
reactivates as the batteries recover
sufficiently to provide the probe with power.
3. The probe begins to run through the LED
review sequence (see page 4.1, “Reviewing
the probe settings”).
LED colour Probe status Graphic hint
Flashing green Probe seated in operating mode
Flashing red Probe triggered in operating mode
Flashing green and blue Probe seated in operating mode – low battery
Flashing red and blue Probe triggered in operating mode – low battery
Constant red Battery dead
Flashing red 
or
Flashing red and green 
or
Sequence when batteries are inserted
Unsuitable battery
Constant blue Probe damaged beyond use
LEDs 
flashing 
green
LEDs 
flashing 
red
LEDs 
flashing 
red
X/Y
Z
Probe status LEDs
4. Again, the batteries discharge and the probe
ceases to function.
5. Again, the batteries recover sufficiently
to provide the probe with power, and the
sequence repeats itself.
Draft 5 16/04/18

5.1
Maintenance
You may undertake the maintenance routines 
described in these instructions.
Further dismantling and repair of Renishaw 
equipment is a highly specialised operation, which 
must be carried out at an authorised Renishaw 
Service Centre.
Equipment requiring repair, overhaul or attention 
under warranty should be returned to your 
supplier.
Cleaning the probe
Wipe the window of the probe with a clean cloth 
to remove machining residue. This should be 
done on a regular basis to maintain optimum 
transmission.
Maintenance
CAUTION: The RMP400 has a glass window. 
Handle with care if broken to avoid injury.
see Section 5,“Maintenance”
Draft 5 16/04/18

5.2
Maintenance
1
2
CAUTIONS:
Do not leave dead batteries in the probe.
When changing batteries, do not allow coolant or 
debris to enter the battery compartment.
When changing batteries, check that the battery 
polarity is correct.
Take care to avoid damaging the battery cassette 
gasket.
Only use specified batteries.
Changing the batteries
CAUTION: Please dispose of dead batteries in 
accordance with local regulations. Never dispose 
of batteries in a fire.
Draft 5 16/04/18

5.3
Maintenance
NOTES:
After removing the old batteries, wait more than 
5 seconds before inserting the new batteries.
Do not mix new and used batteries or battery 
types, as this will result in reduced life and 
damage to the batteries.
Always ensure that the cassette gasket and 
mating surfaces are clean and free from dirt 
before reassembly.
If dead batteries are inadvertently inserted, the 
LEDs will remain a constant red.
3
45
Battery type
½ AA lithium-thionyl chloride (3.6 V) × 2
Ecocel
Saft:
Tadiran:
Xeno:
EB1426
LS 14250C
LS 14250
SL-750
XL-050F
Dubilier:
Maxell:
Sanyo
Tadiran:
Varta:
SB-AA02
ER3S
CR 14250SE 
SL-350, SL-550,  
TL-4902, TL-5902,
TL-2150, TL-5101
CR ½AA
Draft 5 16/04/18

5.4
Maintenance
This page is intentionally left blank.
Draft 5 16/04/18

6.1
Symptom Cause Action
Probe fails to 
power up (no LEDs 
illuminated or fails 
to indicate current 
probe settings).
Dead batteries. Change batteries.
Unsuitable batteries. Fit suitable batteries.
Batteries inserted incorrectly. Check battery insertion/polarity.
Batteries removed for too short a time 
and probe has not reset.
Remove batteries for a minimum 
of 5 seconds.
Poor connection between battery 
cassette mating surfaces and 
contacts.
Remove any dirt and clean the 
contacts before reassembly.
Probe fails to 
switch on.
Dead batteries. Change batteries.
Batteries inserted incorrectly. Check battery insertion/polarity.
Probe out of range. Check position of RMI or RMI-Q, 
(see operating envelope).
No RMI or RMI-Q “start/stop” signal 
(“radio on” method only).
Check RMI or RMI-Q for green 
start LED.
Incorrect spin speed (“spin on” 
method only).
Check spin speed and duration.
Incorrect switch on method 
configured.
Check configuration and alter as 
required.
Incorrect multiple probe mode setting 
configured.
Check configuration and alter as 
required.
RMP400 in hibernation mode (radio 
on method only).
Ensure probe is in range and wait 
up to 30 seconds, then resend 
switch-on signal. 
Check position of RMI or RMI-Q, 
see operating envelope.
Spin on is within 1 second of spin off.  Check for 1 second dwell following 
spin off.
Fault-finding
see Section 6,“Fault-finding”
Draft 5 16/04/18

6.2
Fault-finding
Symptom Cause Action
Machine stops 
unexpectedly during a 
probing cycle. 
Radio link failure/RMP400 out of 
range.
Check interface/receiver and 
remove obstruction.
RMI or RMI-Q receiver/machine 
fault.
Refer to receiver/machine user’s 
guide.
Dead batteries. Change batteries.
Excessive machine vibration 
causing false probe trigger.
Enable enhanced trigger filter.
Probe unable to find target 
surface.
Check that part is correctly 
positioned and that stylus has not 
broken.
Adjacent probe. Reconfigure adjacent probe to low 
power mode and reduce range of 
receiver.
Stylus not given sufficient time to 
settle from a rapid deceleration.
Add a short dwell before the 
probing move (length of dwell will 
depend on stylus length and rate 
of deceleration). Maximum dwell is 
one second.
Probe crashes. Workpiece obstructing probe path. Review probing software.
Probe length offset missing Review probing software.
In cases where there is more than 
one probe on a machine, incorrect 
probe activated.
Review interface wiring or part 
program.
Probe permanently 
triggered.
Probe orientation has changed – 
i.e. from horizontal to vertical.
Select probe “Auto-reset” function.
New stylus has been fitted. Turn probe off and on again.
Probe was switched on when 
stylus was deflected.
Turn probe off and on again. 
Ensure stylus is seated during 
switch on.
Probe has not settled before a 
trigger move occurs following a 
rotation or rapid move (“Auto-
reset” mode only).
Turn probe off and on again, and 
increase the dwell from 0.2 to 
0.5 second dwell before probing 
move.
Probe has collided with an object 
during a rotation or rapid move 
(“Auto-reset” mode only).
Turn probe off and on again.
Draft 5 16/04/18

6.3
Fault-finding
Symptom Cause Action
Poor probe repeatability 
and/or accuracy.
Debris on part or stylus. Clean part and stylus.
Poor tool change repeatability. Redatum probe after each tool 
change.
Loose probe mounting on shank 
or loose stylus.
Check and tighten as appropriate.
Excessive machine vibration. Enable enhanced trigger filter.
Eliminate vibrations.
Calibration out of date and/or 
incorrect offsets.
Review probing software.
Calibration and probing speeds 
not the same.
Review probing software.
Calibration feature has moved. Correct the position.
Measurement occurs as stylus 
leaves surface.
Review probing software.
Measurement occurs within 
the machine’s acceleration and 
deceleration zone.
Review probing software and 
probe filter settings.
Probing speed too high or too 
slow.
Perform simple repeatability trials 
at various speeds.
Temperature variation causes 
machine and workpiece 
movement.
Minimise temperature changes.
Machine tool faulty. Perform health checks on 
machine tool.
RMP400 status LEDs do 
not correspond to RMI 
or RMI-Q status LEDs.
Radio link failure – RMP400 out 
of RMI or RMI-Q range.
Check position of RMI or RMI-Q, 
see operating envelope.
RMP400 has been enclosed/
shielded by metal.
Remove from obstruction.
RMP400 and RMI or RMI-Q are 
not partnered.
Partner RMP400 and RMI or 
RMI-Q.
Draft 5 16/04/18

6.4
Fault-finding
Symptom Cause Action
RMI or RMI-Q error LED 
lit during probing cycle.
Probe not switched on or probe 
timed out.
Change setting. Review switch-off 
method.
Probe out of range. Check position of RMI or RMI-Q, 
see operating envelope.
Dead batteries. Change batteries.
RMP400 and RMI or RMI-Q are 
not partnered.
Partner RMP400 with RMI or 
RMI-Q.
Probe selection error. Verify that one RMP is working 
and is correctly selected.
“Fast” turn-on error. Ensure that all RMPs are ‘Q’ 
marked probes, or change the 
RMI-Q turn-on time to “standard”.
RMI or RMI-Q low 
battery LED lit. 
Low batteries. Change batteries soon.
Reduced range.  Local radio interference. Identify and remove.
Probe fails to switch off. Incorrect “switch-off” method 
configured.
Check configuration and alter as 
required.
No RMI or RMI-Q “start/stop” 
signal (“radio on” method only).
Check RMI or RMI-Q for green 
start LED.
Probe in timeout mode and 
placed in tool magazine and 
being triggered by movement.
Use shorter timeout setting or use 
different switch-off method.
Incorrect spin speed (spin switch 
on only).
Check spin speed.
Spin off is within 1 second of a 
spin on
Check for a 1 second dwell 
following a spin on.
Probe goes into Trigger 
Logic™ configuration 
mode and cannot be 
reset.
Probe was triggered when 
batteries were inserted.
Do not touch the stylus or stylus 
mounting face during battery 
insertion.
Probe status LED shows 
a constant blue
Probe damaged beyond use. Return the probe to your nearest 
Renishaw supplier for repair/
replacement.
Draft 5 16/04/18

7.1
Item Part number Description
RMP400 A-6570-0001 RMP400 probe with batteries, tool kit and quick-start guide 
(factory-set to radio on/radio off).
Battery P-BT03-0007 ½AA battery – lithium-thionyl chloride (pack of two).
Stylus A-5003-7306 50.0 mm (1.97 in) long carbon fibre stylus with Ø6.0 mm 
(0.24 in) ball.
Stylus A-5003-6510 100.0 mm (3.94 in) long carbon fibre stylus with Ø6.0 mm 
(0.24 in) ball.
Stylus A-5003-6511 150.0 mm (5.91 in) long carbon fibre stylus with Ø6.0 mm 
(0.24 in) ball.
Stylus A-5003-6512 200.0 mm (7.88 in) long carbon fibre stylus with Ø6.0 mm 
(0.24 in) ball.
Tool kit A-4071-0060 Probe tool kit comprising Ø1.98 mm stylus tool, 
2.00 mm AF hexagon key and shank grub screw (× 6).
Battery cassette A-4071-0031 Battery cassette assembly.
Battery gasket A-4038-0301 Battery cap gasket kit.
RMI A-4113-0050 RMI (side exit) with 15 m (49.2 ft) cable, tool kit and user’s 
guide.
RMI-Q A-5687-0050 RMI-Q (side exit) with 15 m (49.2 ft) cable, tool kit and 
quick-start guide.
Mounting bracket A-2033-0830 Mounting bracket with fixing screws, washers and nuts.
Styli tool M-5000-3707 Tool for tightening/releasing styli.
Publications. These can be downloaded from our web site at www.renishaw.com.
RMP400 H-6570-8500 Quick-start guide: for rapid set-up of the RMP400 probe.
RMI QSG A-4113-8550 Quick-start guide: for rapid set-up of the RMI.
RMI IG H-4113-8554 Installation guide: for set-up of the RMI.
RMI-Q QSG H-5687-8500 Quick-start guide: for rapid set-up of the RMI-Q.
RMI-Q IG H-5687-8504 Installation guide: for set-up of the RMI-Q.
Styli H-1000-3200 Technical specifications guide: Styli and accessories – or visit 
our Web shop at www.renishaw.com/shop.
Probe software H-2000-2298 Data sheet: Probe software for machine tools – programs and 
features.
Taper shanks H-2000-2011 Data sheet: taper shanks for machine tool probes.
Parts list
see Section 7,“Parts list”
Draft 5 16/04/18

Renishaw plc
New Mills, Wotton-under-Edge
Gloucestershire, GL12 8JR
United Kingdom
T  +44 (0)1453 524524
F  +44 (0)1453 524901
E uk@renishaw.com
www.renishaw.com
For worldwide contact details, visit 
www.renishaw.com/contact
*H-6570-8501-01*
© 2018 Renishaw plc
Issued: ??.????
Part no. H-6570-8501-01-A
Draft 5 16/04/18