Tyco 4100U Earth Fault Search Example, Figure F-1.Earth Fault Example, Continued on next page

Earth Fault Search Example

The illustration below shows a MINIPLEX system with one transponder that has three earth faults:

•SPS NAC on the SPS in the Main Panel

•RPS AUXPWR output on the RPS in Transponder 1

•IDNet channel in Transponder 1

SPS	SPS
	NAC 2
Main
Panel
	RPS
	RUI
	Transponder
	1
= Ground Fault	IDNet

Iso

1

RPS

AUXPW R

Iso	IDNet
	Channel
2
	M2

Figure F-1. Earth Fault Example

The panel reports two earth faults—one for each power supply. The third fault is as yet unreported.

The example below shows the progression of events in finding and repairing the three faults. They are presented as instructions to a technician who does not yet know about the third fault.

A. Find and repair the fault in the main panel.

1.After opening the Earth Fault Search diagnostic menu option, select Location Search.

9.Select the SPS located in the Main Panel (this selects the Main Panel as the location for the search).

10.When prompted, select exclusion of AUXPWR circuits.

11.Start the search. (The panel turns on the earth fault search trouble pseudo-point and the keypad inactivity utility pseudo-point to disable timeout during the search).

12.The search completes. The panel indicates that NAC 2 on the SPS has the earth fault. All slaves are reset (and the panel turns off the earth fault search trouble pseudo-point).

13.Repair the earth fault on NAC 2. When this is done, the trouble from the SPS clears but the trouble from the RPS is still indicated.

Continued on next page

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