simple question on a 1200 input

[plcnewbie]

I have never wired one of these up before and thought I was doing it right but this is what I did and no luck with the input.

I have a pnp sensor. hooking to a micrologix 1200 1762-l40bwa.

black to in22
brown to com2
blue to 24 com

It powers on but I can not get the input to fire???

sorry for the question I am sure Im missing something somewhere.

 

[CroCop]

Do you have the ML1200 common input connected to common 2?

The input has a common connection for multiple channels.

 

[plcnewbie]

all the commons go to the same place. They are all numbered on the wire with a 20

although the 24com is a different number

 

[CroCop]

Where does the COMMON terminal on the PLC wire to?
Is this an already in service with other sensors hooked up?


What you need is the COMMON terminal on the PLC to go to the 24V common, power up the sensor, and wire the output of the sensor to the input of the PLC.

 

[plcnewbie]

common wires to -V
plc is already used for other inputs but i cant trace out wires it is real cramped.
if i go directly from 24 com to input it does fire.
i think my problem is just in wiring the thing.

 

[CroCop]

common wires to -V
plc is already used for other inputs but i cant trace out wires it is real cramped.
if i go directly from 24 com to input it does fire.
i think my problem is just in wiring the thing.

Wiring the thing is very simple.
Figure out your +24
Figure out your Common 24

Connect the brown to the +24
Connect the blue to the Common 24
Connect the black to the input.

That will run the input if your PLC Common is on the Common 24 connection.

 

[plcnewbie]

I thank you for the help.

My problem was that I was using a PNP sensor and trying to follow the rest of the sensors how they were hooked up and it turned out they were all NPN. I got another sensor and my original way worked in the end.

Thanks again for helping me in this dumb mistake I made. It will not happen again.

 

[CroCop]

You're not the first to get a sink/source mixed up.
Glad to see you got it worked out.