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Using Calibration Mode
The 685B-Series has the unique ability to be calibrated using a 4-20 mA simulator. (IMI Sensors model 699A05,
see “Accessories” page) This allows for a much more accurate and quantifiable calibration versus manually
attuning the switch. The following steps allow for simple calibration using this configuration.
1)
Connect the 4-20 mA simulator signal across the COMM and CAL pins.
2)
Turn the calibration dipswitch to “on”. This will disable the switch’s ability to measure physical
vibration.
3)
Turn both time delay potentiometers to “zero” for calibration purposes. This can be adjusted to
desired delay after calibration.
4)
Assume that 4 mA equals zero vibration and 20 mA equals full scale vibration. Then calculate, in mA,
the vibration level for which the alert and alarm switches should trip.
5)
Using the 4-20 mA simulator, send the appropriate alarm signal based on the calculation in the
previous step for the alarm signal.
6)
Adjust the “SP” Alarm set point potentiometer to the point when the red Alarm LED illuminates.
7)
Using the 4-20 mA simulator, repeat step 5 for the Alert signal.
8)
Adjust the “SP” Alert set point potentiometer to the point where the yellow Alert LED illuminates. It is
important to set the Alarm potentiometer first because the Alert signal acts as a percentage of the
value set for Alarm.
9)
Disconnect the 4-20 mA simulator.
10)
Turn “off” the calibration dipswitch.
** Warning: To avoid damage, insure 685B-Series is under power prior to applying
the 4-20mA signal from the simulator. **
Testing the Calibration
Pushing the “Test” button inside the housing simulates full scale vibration and should illuminate both the alert and
alarm LED’s. This feature can be used to adjust time delays to the desired values. This can be accurately
calculated using the “Test” button and a stopwatch.
Connecting the Remote Reset
The 685B-Series allows for remote reset when the switch is in latch mode via a short between the RESET and
COMM pins
.
Connecting the Raw Vibration Output
All models in the 685B-Series
offer the option for obtaining accelerometer’s raw vibration signal. Models with
internal accelerometers output 100 mV/g. To obtain this signal using digital analyzer, turn the ICP® power
OFF
at
the digital analyzer input. Connect the analyzer to the RV OUTPUT and COMM pins with the common connection
on the COMM pin and the signal connection on the RV OUTPUT pin.
