Unknown output pin on micrologix 1200

Hi to all!

Can i ask help on this one. i cant seem to analyze what this pin is for

many thanks to those who will reply!!!

I agree that the output grouping can be a little confusing on MicroLogix controllers.

This model of MicroLogix has a mix of Relay and DC solid-state outputs. Some of the Relays have individual "common" terminals and some have grouped "common" terminals.

V AC DC 0 -> Relay -> Output 0
V AC DC 1 -> Relay -> Output 1
V DC 2 -> Transistors -> Outputs 2,3,4,5,6,7,8,9
V AC DC 3 -> Relays -> Output 10, 11
V AC DC 4 -> Relays -> Output 12, 13, 14, 15

You apply +24V DC to "V DC 2" and 0 V DC to "COM 2", and all the DC outputs on the controller are switched by transistors using that 24V DC source voltage.

The Relays can be used with any source voltage, within the groups indicated.

And this drawing should also help clear up the confusion.

Nice!!!!! Thanks a lot!

another question. if i interchange and apply 0V DC to "V DC 2" and +24 V DC to "COM 2", i could connect the negative terminals of the loads on the plc pins right?

Yes, but only for relay type outputs.

what about on group 2 of this PLC?

As Ken stated in his post, these are the transistor outputs. they are polarity sensitive - you must connect positive to VDC and 0V to COM.