Tech Note 101
Wiring CMCP1100 (ICP) Accelerometers

CMCP1100 Industrial Low Cost Accelerometers are of the “ICP” type, which are the Industry Standard. All ICP accelerometers are powered using a CCD or “Constant Current Diode” between 2 and 10 mA. Portable devices with short cables, to conserve battery life, use a CCD in the range of 2.0 mA. CMCP500 Series Monitors, which may need to power longer lengths of instrument wire, use a 4.4 mA CCD.

Recommended power supply voltage is 24 VDC although supply voltages between 18 and 30 VDC can be used. Bias Output Voltage for the CMCP1100 is usually close to 10.0 VDC and is not dependent on power supply voltage.

Wiring for the CMCP-1100 Accelerometer is very simple however if completed incorrectly permanent damage to the Accelerometer will result.

 ****** Do not wire Accelerometers directly to Power Supply. *******

A Constant Current Diode differs from a regular Diode in that it will pass unlimited current in the reverse direction. Be sure CCD is installed properly polarized or Accelerometer will be damaged.

The following diagram shows how to properly wire an ICP accelerometer to an external power supply and read out device such as a Digital Volt Meter (DVM) or Oscilloscope:

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