IGD 2-Wire Systems, Руководство по установке

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32
V+
4-20mA
V+
4-20mA
4-20 mA Inputs
sinks the signal current on the module PCB
across a 122 Ohm resistor on the PCB
The Input Sources a 24V DC supply then
24V DC Power is supplied
from an external source then
sinks the signal current on
the module PCB across a
100 Ohm resistor on the
PCB. Note if the externally
powered sensor does not
have an isolated output then
a separate isolator must be
fitted as indicated. These
may or may not require
external power. The IGD
Option shown is loop
powered PN TOC-MA-ISO
I/O Port 1
I/O Port 2
Wiring to I/O Port 1 and 2
a) For a 2 Wire Loop Powered Device (4-20MA 24V Option)
b) For a 2 Wire 4-20mA Device Externally Powered Device (4-20MA 0V Option)
Each Detector Node has 2 multi-finction input - output ports. These can be configured
independently as either 4-20mA inputs or solid state outputs. When used as 4-20mA inputs any
standard 4-20mA loop powered can be read in as an analogue signal. Using the setup routine the
signal can be scaled and then read back addressably onto the system controller.
24V DC
4-20mA Signal
0V DC
24V DC
4-20mA Signal
Loop Powered 2 Wire Sensor
Externally Powered 4-20mA
Sensor
External Power
Isolator
+ +
- -