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Vibration Cutout Switch (VCOS)
The Mechanical Vibration Cutout Switch and the Optional Electronic Vibration Cutout Switch
should be tested and field adjusted at start-up and yearly thereafter.
Mechanical Vibration Cutout Switch (Standard)
Set Point Adjustment When Installed:
1. For safety, turn off, then lock and tag-out the electrical supply to the fan motor(s).
2. Turn adjustment screw counterclockwise 1/8 turn at a time until you hear the control trip.
3. Once tripped, rotate adjustment screw ¼ turn clockwise. Push in the manual reset button.
4. Start up the fan(s) to determine if the start-up will cause the cut-out switch to trip.
5. If the VCOS does not trip, start and stop the fan two more times. If the VCOS still does not
trip, then calibration is complete.
6. If the VCOS trips, repeat steps 1 through 5 until calibration is complete.
Electronic Vibration Cutout Switch (Optional)
Two models of electronic vibration cutout switches are available. The single set point model
contains one trip limit for shutdown. The dual set point model contains two independent trip
limits; one for alarm and one for shutdown. The shutdown set-point is factory set at
0.45 in/sec. Additional details can be found in the submittal packet.
Testing:
• The test position sets in the minimum set point so that any vibration will cause a trip
condition.
Remote Reset:
Connection between terminals 5 and 6 latches triac output in alarm state after
set point is exceeded. Opening the connection will reset the output to non-alarm state.
Electrical Reset and Start-up Lockout (Optional):
1. If rated voltage is continuously applied to the reset circuit at unit start-up, the reset
solenoid energizes for a fixed time interval (approximately 30 sec), after which time the
solenoid is automatically de-energized by the thermistor. This provides a trip lockout
during machine start-up roughness.
2. The voltage must be removed from the reset circuit when the machine is stopped to allow
the thermistor to cool off.
3. The switch mechanism can be reset electrically by a momentary application of the reset
voltage or it can be reset manually.
ATTENTION:
The heater control
panel temperature/low level control
can only be used with the supplied
combination temperature/liquid
level sensor probe. Please contact
your local BAC Representative for
replacement parts.
Figure 9.
Electronic VCOS with Alarm Contact is Shown
• The light will come on immediately, and the trip will occur after the
duration of the time delay, proving the complete system is operational.
• If test position is maintained for less than the duration of the time delay,
the trip will not occur, thus permitting the system test without shutdown.
Calibration:
• A light adjacent to the set point control comes on the instant the measured
vibration level exceeds the set point.
• The unit can be periodically calibrated on line by turning the set point
control down until the light comes on. This setting is then compared with
the vibration measured with a portable vibration meter, thus providing a
calibration check of the unit.
• If the trip setting is maintained, trip will occur after the duration of the
time delay.