Section 7 - SPECIFICATIONS
29
7. SPECIFICATIONS
The following specifications apply with a -24 Vdc supply voltage, 100 K
Ω
load, at
77
°
F (25
°
C) unless otherwise specified.
7.1 Accelerometer Interface Module
POWER
Supply Voltage:
-23 Vdc to -26 Vdc
Current Draw:
22 mA maximum
INPUT
Acceleration:
Differential input from a piezoelectric accelerometer
with a sensitivity of 50 pC/g pk or 100 pC/g pk.
Accelerometer pole to pole capacitance plus
extension cable capacitance should not exceed 8300
picofarads.
Overload:
50,000 pC peak for accelerometers with 50 pC/g pk
sensitivity, and 100,000 pC peak for accelerometers
with 100 pC/g pk sensitivity.
ACCELERATION OUTPUT
Sensitivity:
10 mV/g pk (1.02 mV/m/s
2
pk) balanced output, 50
ohm nominal output impedance.
Dynamic Range:
750 gs (7350 m/s
2
) without barriers typical. 500 gs
(4902 m/s
2
) with barriers typical.
Frequency Response:
The low frequency response is controlled by the
charge amplifier. The -3 dB corner is at 4.7 Hz. The
high frequency response is controlled by the
combination of the accelerometer and extension
cable capacitance, the charge amplifier/scaling
stage, and the load capacitance on the acceleration
output buffer. For an accelerometer capacitance of
1000 pF and a cable capacitance of 1000 pF the
upper -3 dB frequency is approximately 5000 Hz.
