Furuno FAR-2157 installation manual How to adjust the overvoltage detection circuit

J105 J106	(P)HV
PWR board	J104
	J103
R21
(OVER)
P108/J108	J101
	AC FIL
8 7 6 5 4 3 2 1

Jumper connector (VH8P)

Processor unit, inside view

How to adjust the overvoltage detection circuit:

1.Add or remove the jumper connector P108 as appropriate and change the fuse, referring to the table on the previous page for details.

2.On the PWR board, set R21 fully clockwise.

3.Connect a variable transformer between ship's mains and the input power terminal board TB- 1 in the processor unit.

4.Adjust the variable transformer output (i.e., input voltage to the processor unit) as follows:

For 100 VAC set: 144 VAC

For 220 VAC set: 288 VAC

5.Turn on the radar and rotate R21 counterclockwise gradually until the overvoltage detection cir- cuit activates (i.e., power supply cuts off).

6.Lower the output voltage of the variable transformer and confirm that the radar automatically turns on with a voltage lower than 142 VAC or 284 VAC.

7.Gradually increase the output voltage of the variable transformer and confirm that the over- voltage detection circuit activates at 144 V or 288 VAC of the variable transformer output.

8.Assemble and connect the processor unit.

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