User Manual

Model GD-70D4H-XX Sample Draw Transmitt er • 6
the opposite end of the tubing to an open area wher e the sample can safely disperse or
to an exhaust duct.
Wiring the GD-70D to a Controller and AC Power
WARNING: Always verify that power to the GD-70D4 H-XX and to the c ontroller are
off and that the controller ’s and GD-70D’s power switches are in the off
position before making wiring connections or adjustments.
1. Turn off power to the controller and the GD-70D4H-XX.
2. Place the controller’s and GD-70D’s power switches in the OFF position.
3. Use the conduit h ubs at the bottom of the GD-70D4H-XX for routing power and
signal cables into the enclosure. Route a 3-wire power cable (18 AWG) and any relay
wiring th rough one conduit hub, and 2- c onductor shielded c able, or two wires in
conduit through the othe r conduit hub to minimize crosstalk.
Figure 4: Ex te rn al Wiring
4. If shielded cable is used for controller wiring, connect the signal cable shield’s drain
wire to a chassis ground at the controller, but do not connect it at the GD-70D4H-XX.
CAUTION: Leave the cable shield’s drain wire insulated and disconnected at the
GD-70D4H-XX. You will connect the opposite end of the cable shield’s drain wire at
the controller.
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ALM1DC24V 4-20mA
ALM2 FAULT
+
-
-
+
GD-70D Terminal Strip
89
10
From
Power
Supply
Alarm
Device
Alarm
Device
(+) H
AC Term i n al Strip
Strobe
Light
100-240 VAC
HNG
4 - 20 mA In (FB)
- ( DC Ground)
Controller
(-) N
External Power
Source
+ (No Connection)
(+) H
(-) N
External Power
Source