Detcon 140 - Manual (Page 5)

140 Operators Manual
Model 140 Operator Manual Rev. 1.8 Page 1 of 29
1.
Description
Housed in a NEMA 4X weatherproof enclosure, the Detcon Model
140-N4X Gas Detection Alarm System has the capability to handle
one 4-20mA sensor input or one RS-485 serial sensor input. The
remotely mounted gas sensor (purchased separately) can include any
Detcon 4-20mA or RS-485 serial input device such as combustible
gas, toxic gas, or oxygen deficiency sensor.
The system displays real time channel information on a backlit
LCD. Configuration inputs are completely field-programmable and
include channel number, gas type, and gas concentration. It also
shows the current Alarm/Fault status via front panel LED indicators.
Standard features include recorded history of Time Weighted
Average (TWA), Peak readings, and Alarm/Fault/Maintenance
Events. Additional features include one-touch Alarm Reset and
Alarm Silence (Acknowledge) functions.
The Model 140-N4X has a built-in power supply, giving the user a multitude of power options. It can be
powered by either 115/230VAC or 11.5 to 30VDC, and has an optional one-hour battery backup in the
event of temporary power loss.
Each control channel has three field programmable alarm relays and one fault relay. The relays have two
discrete form “C” contacts and are rated for 5 Amps at 30VDC and 250VAC. The low, high, and high-high
alarms have individually field adjustable set points for each gas channel and include the provision to
configure the alarm relays in a normally energized (failsafe) or normally de-energized mode of operation.
The low, high, high-high and fault alarm relays may also be configured for latching / non-latching and
silenceable / non-silenceable operation.