The Endevco > ծ model 87 is a piezoelectric accelerometer with integral electronics, designed specifically for measuring ultra-low level, seismic events and low frequency vibration on structures and objects. The unit is hermetically sealed against environmental contamination, features a 1 V/g or 10 V/g sensitivity, state-of-the-art signal-to-noise ratio, and near-dc frequency response. The model 87 incorporates an advanced ultra low noise hybrid circuit operating in a constant current mode. A simple two-wire system transmits its low-impedance voltage output and the required power. Signal ground is isolated from the outer case and mounting surface to prevent ground loops. A specially designed cable assembly is available as an optional accessory. > Sensitivity deviation (%) Temp [˚C] Typical temperature response Sensitivity deviation in % Frequency in Hz size="-2">

The following performance specifications conform to ISA-RP-37.2 (1964) and are typical values, referenced at +75˚F (+24˚C) and 100 Hz, unless otherwise noted. Calibration data, traceable to National Institute of Standards and Technology (NIST), is supplied. > Range g 5 ѱ0.5 Voltage sensitivity, 10% V/g 1 10 Frequency response (ref @ 20 Hz) See typical curve Resonance frequency Hz 1220 1220 Hz 0.015і380 0.05380 Amplitude response ֱ3 dB Transverse sensitivity, typical % < 0.5 Temperature response ˚F (˚C) See typical curve Amplitude non-linearity % < 1 > Output polarity Acceleration directed into...