Cable Types And Specification; Earth Connection - Simtronics GD1 MK3 Operating Manual

2.5.2.

Cable types and specification

Cables must be chosen in accordance with applicable regulations.
System cable:
Cable from the GD1 system to control system. The table below indicates maximum cable
lengths (2-wire) restrictions due to voltage drop over the power supply cable.
Min. single wire cross area
Supply voltage 24 VDC, terminal 1.
Max length.
Supply voltage 0 V Return on
terminal 2.
Max length.
Primary Loop, terminal 7.
*The GD1 is by default delivered with terminal blocks for wires up to 2.5 mm
TX / RX communication cable:
Cable between the GD1 Transmitter and Receiver, containing data and power supply. The
cable shall be an instrument type with 2 twisted, individually shielded pairs and with an
overall shield. Wiring up to 200 meters shall have a minimum cross section of 0.75 mm
For longer distances the maximum impedance of 70  must be considered.
2.5.3.

Earth connection

The detector housing must be connected to local earth via the external earth point. The
wire should be minimum 4 mm
GD1
2
0.75 mm
125 m
The wiring should be such that the total
impedance of the current loop, including cabling,
connections and input on control system should be
maximum 500 .
2 (8 AWG) and as short as possible.
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2
1.25mm 2.5 mm
250 m 400 m
Earth point
850-816926-EN R06
2 2
4.0 mm *
800 m*
2
.
2
.