Accepting Alarm Conditions - General Monitors 4802A Instruction Manual

All of the relay contacts on the Model 4802A have a maximum rating of:
• 4A @ 30V RMS/42.4V Pk., 3A @ 30Vdc resistive
The following outputs have rear terminal open collectors:
• A1 Alarm & LED Mimic
• A2 Alarm & LED Mimic
• Fault
• UA - Unaccepted Alarm
• FUA - Unaccepted Fault
• CAL/INH - Inhibit, Calibration & Calibration Check Modes
All of the open collector outputs on the Model 4802A have a maximum rating of:
• 100mA @ 35Vdc
• The Analog Output Signal is used for sending gas concentrations and status
information to remote devices. The maximum analog load may not exceed 500 ohms
including the wire/cable that the signal is sent on.
The Analog Output is a 0 to 22mA current signal with 4 to 20mA being proportional to 0
to 100% of full scale.
When the Model 4802A is placed in the calibration, calibration check, setup, setup
check or inhibit mode a 1.5mA signal is generated by this output. During the calibration
mode the digital display will indicate prompts associated with the calibration procedure.
During the calibration check mode, the digital display will indicate the gas concentration
with a flashing digit, or pair of digits.
When the Model 4802A enters into a fault condition a 0mA signal is generated by this
output. During a fault the display will indicate a fault code ("F" followed by a digit).
If the sensor attached to the Model 4802A is seeing gas in excess of 100% of full scale,
this output will generate a signal between 20 and 21.7mA (not proportional). An over
range condition is indicated by a flashing digital display reading full-scale (99).
Overrange conditions are latching.
4.4

Accepting Alarm Conditions

Whenever a new alarm condition occurs, the front panel LED and open collector
associated with that alarm (LA1 or LA2) would begin to flash. In addition, the associated
alarm outputs and the unaccept outputs (4802A UA open collector & FM002A UA relay)
will activate, unless they are already activated. The flashing front panel alarm LED and
rear terminal open collector indicate that a new alarm has been activated. New alarms
should be acknowledged, or accepted. This is accomplished with the Master Accept
Button located on the Facilities Module, (FM002A).
Pressing the Master Accept Button de-activates the UA outputs and causes the
associated front-panel alarm LED, and rear terminal open collector to stop flashing and
energize.
NOTE - Alarms that latch must be Accepted before they can be Reset (see Section 5.5).
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Model 4802A