OmniCare EVC System
Installation & Commissioning Manual
70
OmniCare issue 1
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6.1.1 Description of 0V Continuity Check
Figure 6.1 — Illustration of 0V Continuity Check
This should be the first check that is made:
• No Power is required so there is no risk of damaging Remote
Units,
• It ensures a continuous copper link along the length of the
loop,
• After successfully completing the 0V check, Power can be
safely applied to the loop:
Checking the 0V cable ensures that power cables are not
transposed (0V to +V and vice versa), and also that the 0V
cable is not connected to CAN H or CAN L.
• Successfully completing this test reduces the scope of further
wiring faults from 4 wires to 3 wires.
Refer to Section 6.2.1 for details.
6.1.2 Check Terminations on Remote Units
The majority of faults are due to loose, poor or incorrect
terminations on Remote Units.