Detcon 500-503200-000 Signal Zoning Module - Manual

Signal Zoning Module - Part #500-503200-000
Gas Detection System Accessory
Operator's Instruction Manual
D ESCRIPTION
Detcon Part #500-503200-000 signal zoning module is a 4-20 MA multiplexer designed to receive up to 8
inputs and continuously output the highest signal. The circuit can be used to zone sensors to a single con-
trol module, computer or other recording device, reducing installation cost while expanding detection cov-
erage. Field wiring from the controller to the zoning module consists of 4 conductors; +24 VDC, common,
+4-20 MA and signal common.
Note: All 4-20 milliamp signals (8 inputs and 1 output) must loop to the same common (-24
VDC) source.
Z ERO AND S PAN A DJUSTMENTS
The zero and span adjust potentiometers are factory set and should require no further adjustment. If
adjustment is necessary follow the procedure below to calibrate.
Tools required: Jewelers screwdriver and a digital volt-ohm meter capable of reading milliamps DC.
01. Remove all signal inputs from the signal input connector.
02. Install a 250 ohm resistor from the 4-20 MA output terminal to the common terminal.
03. Place the digital test probes in TP1 (+) and TP2 (–).
04. Adjust the zero potentiometer (R9) until the volt-meter reads 40 millivolts (this corresponds to 4 MA).
05. Input a 20 milliamp signal into one of the 8 signal input terminals.
06. Adjust the span potentiometer R12 until the volt-meter reads 200 millivolts (this corresponds to 20 MA).
Calibration is complete.
Shipping address: 3200 A-1 Research Forest Dr., The Woodlands, Texas 77381
Mailing address: P.O. Box 8067, The Woodlands, Texas 77387-8067 ❏ Phone: (281) 367-4100 ❏ Fax: (281) 292-2860
detcon inc.
TP2 TP1
24
MA
1
2
3
4
6
7
8
5
R9 ZERO
R12 SPAN 24 VDC IN
4-20 MA OUT (Loop to Common)
DISCREET 4-20 MA INPUTS
Zero and Span adjustments are factory set.