Introduction

The P702B power unit/amplifier is a portable power source with integral signal conditioning for use with

internally amplified accelerometers. Signal conditioning includes amplification, integration and fault

indication.

Description

The P702B power unit/amplifier is a portable unit specifically designed to furnish 2.4 mA constant DC

current (+27 VDC) necessary to operate the internal charge amplifiers of Meggitt Sensing Systems and

similar piezoelectric transducers (accelerometers and velocity sensors.) In addition the P702B provides

signal conditioning, includes features such as selectable gain levels of 1. 10. 100. extremely low-noise,

integration to yield velocity output, battery condition indication, and visible overload or open/shorted cable

indication. This gives the test engineer broad capabilities for the accurate measurement and recording of

vibration signals over a wide range of test situations. Also virtually any high impedance charge-type

accelerometer can be operated with the P702B with the addition optional charge converter accessory,

CC701. The P702B also has built-in ESD protection to guard against damage of the internal electronics.

All switches and controls are on the front panel. Transducer input and output BNC connectors are

located on the rear panel, as is a connector for the optional line adapter/charger, See Figure 1 in the

appendix.

The P702BF-1 is identical to P702B, except that the frequency response of the P702BF-1 is specified as

–3 dB from 0.5 Hz to 20 kHz (versus 0.5 Hz to 50 kHz for the P702B) in acceleration mode. Other than

the high end frequency response, the P702BF-1 is identical to the P702B in terms of operation,

maintenance and troubleshooting.