Emerson 2468CD, 2468CB manual 3c-11

Hydrastep 2468CB & 2468CD Manual Opto-isolated Output Board Option

3c.3.2.4 ‘Two out of Two’ Opto-output Alarm System

This system requires both opto-outputs to operate to cause an alarm when their assigned electrodes register an alarm condition.

Case A - Opto-output circuit normally open circuit, short circuit both to trip

			To alarm annunciator or
			tripping device
TR2	1	PL 2	+ VE - VE	PL 2
	2
	3
Opto-output 1	4

Odd Electrodes	Note:	External power must
(RH Input Board)
		be applied as shown.
		See specification for
		power requirements

1

2

3

4

TR2

Opto-output 1

Even Electrodes (LH Input Board)

(Switch SW5 is set to S for low level alarms and set to W for high level alarms)

Case B - Opto-output circuit normally short circuit, open circuit both to trip

To alarm annunciator or

tripping device

TR2	1	PL 2	+ VE	- VE	PL 2	1
	2					2
	3					3
Opto-output 1	4					4

Odd Electrodes	Note:	External power must
(RH Input Board)
		be applied as shown.
		See specification for
		power requirements

TR2

Opto-output 1

Even Electrodes (LH Input Board)

(Switch SW5 is set to W for low level alarms and set to S for high level alarms)

24685034 3c-11