S4000C
Figure 10: Relay Reset
3. The relays can be reset via the Remote Reset input terminals on TB2. Connect a
normally open switch between terminal TB2-7 and TB2-8. Closing the switch
momentarily will reset the relays. General Monitors explosion-proof switch, P/N 30051-
1, can be used for this purpose. See Section 9.6 for ordering instructions.
NOTE:
Red LED’s above and below the digital display indicate that the Alarm and Warn relays
are active. Latching relays can only be reset if the gas concentration has fallen below
the respective relay set point.
4.4 User Selectable Options
The Model S4000C Intelligent Sensor includes many selectable options to provide the user with
the most flexible combustible gas detector possible. These options include Adjustable
Calibration Level, Warn and Alarm Relay Set Points and Configuration, and MODBUS
Communications Settings. These allow the unit to operate with a wide variety of PLC and DCS
Systems. The following sections explain the available options and how they can be customized.
A flow diagram is included to help the user in understanding the process of reviewing and
changing the available options (Figure 11).
NOTE:
If the unit was ordered without relays or MODBUS communications, changing relay or
MODBUS settings will have no effect on the operation of the unit.
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