Detcon 412B-FB User Manual
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Table of Contents
1.0 Introduction
1.1 Description
1.2 Specifications
1.3 Multiple Alarm Relay Circuit
1.4 Alarm Disable
1.5 Remote Alarm Reset
1.6 Installation
1.7 Start-up
1.8 Maintenance & Repair
1.9 Spare Parts List
1.10 Warranty
1.0 I
NTRODUCTION
Detcon Model 412B-FB consists of 3 major assemblies:
1. The NEMA 4 fiberglass control enclosure.
2. The Model 12B single channel digital control modules.
3. The remote mount gas sensor assemblies.
The NEMA 4 control enclosure is detailed in section 1.0 of the manual, the control modules in section 2.0, and
applicable sensor assemblies in section 3.0.
1.1 D
ESCRIPTION
Detcon Model 412B-FB control enclosure, along with Model 12B digital control modules, is designed to serve as a
host assembly for up to four remote mount gas detection sensor assemblies. The control enclosure is rated NEMA
4X, which is by definition rain tight, and therefore suitable for outdoor location in electrically non-hazardous envi-
ronments.
The single channel modular design supports application flexibility wherein multiple function gas detection systems
can be configured in any combination up to four channels. All control modules are plug-in front panel accessible
for easy maintenance and repair. The system is powered by VAC line power and/or 24VDC unless otherwise speci-
fied at time of order.
The control enclosure includes, as standard operating controls; a power on/off switch, an alarm disable switch and
a line power fuse. Discrete output terminal strips located on the controller motherboard are provided for sensor ter-
minations, Form C dry contact alarm outputs for three alarms plus fault (common and choice of normally open or
normally closed), 4-20 mA outputs for remote recording devices, and RS-485 serial Modbus™ output. Terminations
are provided for VAC power in, VDC power in, and remote alarm reset. A multiple alarm relay circuit card is also
provided along with its respective logic and power terminations.
The Form C relay outputs, may be discrete, zoned, or common by gold plated jumper tabs located on the con-
troller mother board.
Model 412B-FB NEMA 4 Control Enclosure PG.2