Model 4802A
14
4.0 Operation
This chapter discusses what general maintenance to perform and describes the
electrical inputs, outputs, accepting & resetting alarm & fault conditions and fault
diagnostics.
4.1 General
Maintenance
Once the Model 4802A has been installed, very little maintenance is required other than
periodic checks to verify the integrity of the system.
•
The user should evaluate conditions at the sensor site to determine how frequent
calibration checks should be performed.
•
A functional test of the system should be performed at least once each year. This
test should include full operation of stand-by systems or back up power for the
prescribed period.
•
The power, sensor and output wiring should be checked for tightness, verifying that
all of the components and devices are connected correctly.
•
If the “Password” is disabled, periodic checks of the setup parameters should be
performed.
4.2 Electrical
Inputs
There are two electrical inputs to the Model 4802A. They are the:
•
General Monitors Catalytic Bead Sensor (field device) and
•
Card Test input
Both of these input connections (sensor and card test) are made to the rear terminal
block (see Chapter 3 for more detailed installation information).
•
The Catalytic Bead Sensor input consists of the standard three lead connections used
with General Monitors Catalytic Bead Sensors, see Figure 31.
•
The Card Test input consists of a single termination for remote testing of the Model
4802A’s functions. For detailed information on the Card Test, refer to Figure 33.
4.3 Electrical
Outputs
The electrical outputs on the Model 4802A consist of relay contacts, open collectors and
an analog current signal.
The following outputs have rear terminal relay contacts:
Output
Rear Terminal Relay
Contacts
A1 Alarm
DPDT relay contacts
A2 Alarm
DPDT relay contacts
Fault
SPDT relay contacts
Figure 37 – Rear Terminal Relay Contacts
