Combinations of Relay Units
There are several useful ways in which multiple relay units can be interconnected. In these
illustrations the connections to the reader and PC are not shown.
Bi-Directional
When you want to have readers both sides of the door, you need to combine the relay contacts.
These wiring patterns can be used in combination with the power supply sharing wiring pattern
above. The wiring pattern you should use depends on which relay contacts are being used.
Normally Open Contacts
In arrangements where the normally open (NO) contacts are used, wire the relays in parallel.
Change this:
To this:
Normally Closed Contacts
In arrangements where the normally closed (NC) contacts are used, wire the relays in series.
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