This is a very simple circuit that can indicate the last action taken on a Momentary Switch. An example of this is if you are using a momentary toggle switch to control the points on a Model Rail Layout. This circuit will latch on an Indicator when the switch is used, that indicator will remain ON when the switch returns to the centre OFF position. When the switch is used in the down momentary position the first indicator will switch OFF and the second Indicator will switch ON, and remain like that even when the switch returns to the centre OFF position.

Now voltages:  The circuit is capable of accepting a range of voltages.

Coil 1 – C1 = 9v to 16v ACDC,

Coil 2 – C2 = 9v to 16v ACDC,

The Relay contacts will handle 2 Amps upto 30vDC ( A suggestion fix the circuit board near the points it is controlling, then run a 6 core cable back to the Control Panel for Indicators and the toggle switch, this assumes you have a 0v (Black) Bus Bar.)

Under no circumstances run a CDU through the relay contacts, the relay will fail.


MR204 Latching Switch

SKU: MR204

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