www.bksv.com BRÜEL&KJÆR Power Amplifiers Product Data BP1928–14 Power Amplifier Type 2718 Power Amplifier Type 2718 has been designed to drive small vibration exciters, particularly Vibration Exciter Type 4809, which
BRÜEL & KJÆR® Power Amplifiers Power Amplifier Type 2718 Power Amplifier Type 2718 has been designed to drive small vibration exciters, particularly Vibration Exciter Type 4809, which has a force rating of 45 N (10 lbf) sine peak, and Mini-shaker Type 4810, which has a force rating of 10 N (2.25 lbf) sine peak. Type 2718 provides a flat frequency response and low harmonic distortion over a wide frequency range and has extensive control and monitoring capabilities. Uses · Drives Vibration Exciter Type 4809 · Drives Mini-shaker Type 4810 safely to full rating · General purpose power amplifier for small vibration exciters requiring up to 75 VA in 3 Features · 75 VA power output capacity in 3 · Continuously variable current limit from 1 A to 5 A (RMS) · 40 dB voltage gain · Built-in attenuator and continuously variable gain control · Low distortion over wide frequency range · Built-in protection against short-circuit and excessive heat sink temperature · LEDs on front panel showing distortion (clipped output signal), temperature overload, current overload, output signal phase (0° or 180°) and power status · Liquid crystal display (LCD) showing output current and voltage · Monitor output connectors (voltage and current) on back panel Description Power Amplifier Type 2718 has a flat frequency response from 10 Hz to 20 kHz (±0.5 dB). The power output capacity is 75 VA into a 3 exciter or resistive load, and the maximum voltage gain is 40 dB. This enables the power amplifier to be used in acoustical measurement setups, even when third-octave, narrow-band noise is employed. The use of a transformerless power output stage and high negative feedback results in very low harmonic distortion. A balanced preamplifier and rugged solid-state design results in a stable instrument which can tolerate temperature fluctuations and supply line variations. Fig. 1 Simplified block diagram of Power Amplifier Type 2718 Cont. Variable Current Limit 1 A to 5 A (RMS) Input Input Aenuator 10 mF Coupling Capacitor Driver Power Amplifier Gain Control Preamplifier Temperature Sensor 272084/4 Monitoring The front panel has extensive monitoring capabilities including an LCD that shows output current and output voltage and LEDs that light up when the instrument is in the following states: distortion, temperature overload, current overload, stand-by status and power on. The output current and voltage can also be monitored using two BNC connectors on the back panel. Clipping Detection The input circuitry of Type 2718 includes a continuously variable attenuator for attenuation of the input signal. This is followed by a gain control, in 10 dB steps from 0 to 40 dB, and a preamplifier. The preamplifier is capacitively-coupled to the driver stage, which is equipped with a clipping detector. Excessive signal levels at the input will saturate the amplifier and cause clipping of the output waveform. This will trigger the clipping detector, which then lights the yellow distortion warning LED on the front panel. The instrument remains in operation during clipping. Temperature Protection The power stage employs an output current limiter, which limits the instantaneous positive and negative peaks of the output current. The power output stage is protected by a temperature sensing device. Abnormal load conditions, high ambient temperatures or an output short-circuit could result in output transistor temperatures well in excess of design limits. To prevent any subsequent damage, the temperature protective circuitry blocks the amplifier input signal. When the heat-sink temperature reverts to the normal level, the power amplifier will automatically regain operation. Phase Shift The output signal can be phase inverted (0° or 180°) by use of the phase inversion switch at the front panel. Two LEDs one for each of the two possible positions indicates the chosen output phase. www.bksv.com Product Data BP 1928 14 ËBP-1928---^Î BP 1928 14 2021-06 © Hottinger Brüel&Kjær A/S. All rights reserved. Specifications Power Amplifier Type 2718 COMPLIANCE WITH STANDARDS The CE marking is the manufacturer's declaration that the product meets the requirements of the applicable EU directives RCM mark indicates compliance with applicable ACMA technical standards that is, for telecommunications, radio communications, EMC and EME China RoHS mark indicates compliance with administrative measures on the control of pollution caused by electronic information products according to the Ministry of Information Industries of the People's Republic of China WEEE mark indicates compliance with the EU WEEE Directive Safety, EMC Emission and Immunity: According to relevant standards: · EN/IEC 61010 1, UL 610101 · EN/IEC 6100062 · EN/IEC 6100064 · CISPR32 Class A limit · FCC Rules Part 15 Temperature: According to IEC 6006821 and IEC 6006822 · Operating temperature: +5 to +40 °C (41 to 104 °F) · Storage temperature: 25 to +70 °C (13 to 158 °F) Humidity: According to IEC 60068278, Damp Heat: 93% RH (non-condensing at 40 °C (104 °F)) Mechanical: Non-operating according to IEC 6006826, IEC 60068227, IEC 60068229 Enclosure: According to IEC 60529 POWER OUTPUT CAPACITY 75 VA into 3 exciter or resistive load Connectors (back panel): · 4-pin Neutrik® speakON® connector (for Vibration Exciter Type 4809) · 10 32 UNF Microdot socket (for Mini-shaker Type 4810), current limited to 3 A CURRENT LIMITING Continuous adjustment potentiometer Max. 5 A for Vibration Exciter Type 4809 Max. 1.8 A for Mini-shaker Type 4810 FREQUENCY RESPONSE (20 dB GAIN) 10 Hz to 20 kHz (± 0.5 dB) 4 Hz to 40 kHz (± 3 dB) HARMONIC DISTORTION <0.1 % (20 Hz to 10 kHz) <0.2 % (20 Hz to 20 kHz) At full output capacity INPUT IMPEDANCE 15 k OUTPUT IMPEDANCE <0.04 (10 Hz to 5 kHz) <0.08 (5 kHz to 20 kHz) PROTECTION Current overload Excessive heat sink temperature DC STABILITY <25 mV drift for ±10% supply line variation <25 mV drift for ambient temperature variations between 10 and 40 °C (50 and 104 °F) HUM AND NOISE FLOOR, UNWEIGHTED 100 dB below full output (20 Hz to 20 kHz) MAX. VOLTAGE GAIN AT 1 kHz 40 dB (±1 dB) CONTROLS Power on/off Gain control, 0 to with integral reset Amplifier gain, 0, 10, 20, 30 and 40 dB steps Current limit, adjustable, 1 A to 5 A (RMS) INDICATOR LAMPS (LEDs) Power on Distortion Temperature overload Current overload Phase shift: 0° or 180° MULTIFUNCTION DISPLAY (LCD) Voltage (RMS) read-out accuracy ±3%, 50 Hz to 20 kHz Current (RMS) read-out accuracy ±3%, 50 Hz to 20 kHz MONITOR OUTPUT Voltage: 0.1 V/V ±3%, 2 Hz to 35 kHz Current: 0.1 V/A ±3%, 2 Hz to 35 kHz Connectors: 2 separate BNC sockets (back panel) POWER REQUIREMENTS Single phase 100, 120 or 230 V AC (± 10%, 50 to 60 Hz), Approx. 140 VA at full load FUSES 100 V or 120 V: T 2.5 A slow blow 230 V: T 1.25 A slow blow DIMENSIONS Height: 88 mm (3.5 in), equivalent to 2 RU (rack unit) Width: 482.6 mm (19 in) with flanges for standard 19-inch rack mounting Depth: 450 mm (17.7 in) WEIGHT 13.3 kg (29.3 lb) Ordering Information Type 2718 Power Amplifier Includes the following: · Mains cable OPTIONAL ACCESSORIES WL-1325-D-050 Cable, 4-pin Neutrik speakON connector to two banana plugs, length 5 m (16.4 ft), for use with Vibration Exciter Type 4809 (included with Type 4809) AO-0038-D-012 Cable, super low-noise, 1032 UNF plug to 1032 UNF plug, 1.2 m (4.0 ft), for use with Type 4810 Note: Cables are available in different lengths. Skodsborgvej 307 · DK-2850 Nærum · Denmark Telephone: +45 77 41 20 00 · Fax: +45 45 80 14 05 www.bksv.com · info@hbkworld.com Local representatives and service organizations worldwide To learn more about all HBK offerings, please visit hbkworld.com Although reasonable care has been taken to ensure the information in this document is accurate, nothing herein can be construed to imply representation or warranty as to its accuracy, currency or completeness, nor is it intended to form the basis of any contract. Content is subject to change without notice contact HBK for the latest version of this document. Brüel & Kjær and all other trademarks, service marks, trade names, logos and product names are the property of Hottinger Brüel & Kjær A/S or a third-party company.Acrobat Distiller 21.0 (Windows)