Installation
EST3 Installation and Service Manual 5.21
Table 5-3: Field wiring tests
Circuit type Test
RS-232 Communication
Circuits
With both ends of the circuit disconnected:
1. Verify the continuity of each conductor. Each conductor
should measure between 0 and 25 Ω.
2. Measure the resistance between conductors. The circuit
resistance between conductors should be infinite.
3. Measure the resistance between each conductor and earth
ground. The circuit resistance between a conductors and
earth ground should be infinite.
Earth Ground 1. Measure the resistance between the earth ground terminal
and a convenient water pipe or electrical conduit. The circuit
resistance should be less than 0.1Ω