Det-Tronics OPECL Infrared Hydrocarbon Gas Detector - Manual (Page 5)

3 95-8556 10.1
COmmUNICaTION
The standard OPECL system provides an analog 4-20
mA signal output, with HART and RS-485 MODBUS serial
communication from the receiver module. EQP Models
communicate with the EQP controller over the LON.
RECORDINg CapabIlITy
Non-volatile memory is provided to save the 10 most
recent calibrations, alarm/fault events, and minimum/
maximum operating temperature history. A real time
clock is provided to record operating service time and to
time stamp events. This information is accessible using
HART and MODBUS communication, or S3 software for
EQP models.
DETECTION RaNgE
The standard OPECL system can cover a range of 5 to
120 meters.
opERation
mODUlE IDENTIfICaTION
While the OPECL transmitter and receiver modules
appear physically identical, each module is labeled as
“transmitter” or “receiver” on the enclosure. The physical
mounting requirements for both modules are generally
identical. However, there are functional and electrical
characteristic differences as identified in Table 1.
Table 1—Functional and Electrical Comparison of Transmitter and Receiver
Characteristic Transmitter (Tx) Receiver (Rx)
Functional Description Contains primary and backup xenon
flashlamps, and generates optical
energy to enable hydrocarbon
detection. Contains opto-electronics, signal processing and
output drivers, and diagnostic electronics.
Power Consumption 5.0 watts nominal @ 24 Vdc.
5.8 watts peak @ 24 Vdc. 6.0 watts nominal @ 24 Vdc (without relays).
6.4 watts nominal @ 24 Vdc (with relays).
Electrical Connections 2 power connections only.
(+24 Vdc and –24 Vdc). From 3-7 connections depending upon specific
configuration (separate power and signal cables
recommended).
Onboard HART Communication
Port N/A Connection to handheld HART communicator for
system setup, commissioning, and diagnostics.
Onboard LED Indicator Indicates normal, fault, and backup
lamp operation status.
Green indicates normal operation.
Yellow indicates operation in “back-up
lamp” mode or other fault condition. Indicates normal, alarm, fault, and calibration status.
Green indicates normal operation. Blinking red
indicates low gas alarm condition.
Steady red indicates high gas alarm condition.
Yellow indicates operation in “back-up lamp” mode
or system fault.
Calibration status is indicated by a steady red
indication after Calibration command.
LED operation for fault status is non-latching. LED
operation for gas alarms is configurable for latching/
non-latching.
Magnetic Calibration Switch
(See Figure 2 for switch location.) Momentary activation overrides back-
up lamp fault flash coding sequence,
permitting normal receiver operation
with back-up lamp. Momentary activation provides reset function for
latched alarm outputs. Activation for longer than 2
seconds will initiate zero calibration.
Factory Default Settings No programmable options Factory calibrated for methane, 0-5 LFL-meters
full scale. See Table 2 for receiver factory default
settings. HART communication is required to
change the factory default settings.