Screening Services & Training LLC                                                                                                                                       Last Update 10/28/2015
25092 Natama Ct                                                                                                             .
Laguna Hills, CA  92653-5607

How to:  Calibrate the SCM-100 Accelerometer Electronics using the Individual Accelerometer Sensitivities.

This procedure applies to systems manufactured by Screening Systems, Inc. that use the SSC-2000 model vibration controller driving the SCM-100 interface.

When the accelerometer transducers are calibrated a calibration sheet is generated for each accelerometer.  These sheets include the actual transducer sensitivity in millivolts per g acceleration (mV/g).  Instead of using the SCM-100 Internal Signal Generator to calibrate all the SCM-100 accelerometer electronics to the same sensitivity, each accelerometer electronics channel may be calibrated to match the individual transducer connected to that channel.

To perform this procedure, connect an external sine-wave function generator (FG) to the first accelerometer channel; Control Accelerometer 1 (X1) BNC accelerometer input connector.  Set the FG to the millivolt sensitivity times 10 +/- 0.5 mVrms for the particular accelerometer connected to this input.  Set the FG to 464 +/- 10 Hz. sine-wave output. For example, if the accelerometer that will be connected to this channel has a sensitivity of 5 mV/g, set the function generator to 50.0 millivolts
RMS and set the Input Level to10.00 gRMS.  Or, if the transducer sensitivity is 9.87 mV/g, set the FG to 98.7 millivolts RMS and the Input Level to 10.00 gRMS.

Select “START (F2)” and wait until the Seconds down-counter reaches zero.  If the accelerometer channel being calibrated is a Control Accelerometer, select the corresponding Averager Control Accelerometer Input Channel bar and select “START (F2)” again.

When the Seconds down-counter has again reached zero, either repeat the above steps for each additional accelerometer channel to be calibrated or if all calibrations are completed, select “EXIT (F1)” and "YES" to save the new calibration data.  Be sure to calibrate the Averager Auxiliary1 Accelerometer 1 (X1) through Averager Auxiliary 1 Accelerometer 6 (Z2) to match any product response accelerometer sensitivities by inputting the FG to the appropriate Auxiliary Accelerometer Input BNC connectors.

For systems that include an additional twelve response accelerometer input circuits, calibrate Averager Auxiliary 2 Accelerometer 1 (X1) through Averager Auxiliary 3 Accelerometer 6 (Z2) to match any product response accelerometer sensitivities by inputting the FG to the appropriate Auxiliary Input BNC connectors.

This completes the calibration procedure.

For technical assistance contact Screening Services & Training LLC  via e-mail.