Ametek Dycor CG1100 Series User Manual page 31

Loop-Powered
4-to-20 mA output, Loop-Powered Connector
Internal Jumper JP5 - Jumper Pins 1-2 and 3-4.
Analog/Digital I/O Connector
Cable should be shielded with single twisted pair. Cable shields should be tied to the chassis at each CG1100. If this
is not possible (e.g., ground loop), tie the shield at the PC or DCS to chassis and remaining shield to earth through a
0.1uf @ 500v capacitor.
Self-Powered
Total RS-485 cable length
not to exceed 4000 feet
(1219 meters).
Figure 3-9. 4-to-20 mA output wiring.
3 4
(-) (+)
4-to-20 mA output, Self-Powered Connector
Internal Jumper JP5 - Jumper Pins 2-3 and 4-5.
Analog/Digital I/O Connector
3
(-) (+)
Cable should be shielded with single twisted pair. Cable shields should be tied to the chassis at each CG1100. If this
is not possible (e.g., ground loop), tie the shield at the PC or DCS to chassis and remaining shield to earth through a
0.1uf @ 500v capacitor.
The external voltage source must be no greater
than 30 volts DC. To determine the minimum
external voltage supply required to power the
current outputs, use the following formula:
VEXTmin = .02 amps (RLoad + Rwires) + 6 volts.
+
R
Load
+ -
External 24V DC Supply
4
+
VEXTmin = minimum
external voltage required to
power current output circuit.
-
RWires = resistance of the
wires.
-
R
Load
Installation | 3-13