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PNP (sourcing) or NPN (sinking) Photocell

Issue

I connected the photocell but I don’t see it in the controller.

What am I doing wrong?

Check whether you have a NPN or PNP photocell

 

 

Let’s look at input 1 in the gray box. You have 3 contacts: GND, SIG, 24 VDC

 

0   24 VDC

0   SIGNAL in the middle

0   GND

 

If you go to Service/Peripheral, you see every input on the left.

No photocell, if you put a cable between GND and Signal and you see input 1 in the controller screen, you have a NPN input (see also manual)

 

0        24 VDC

|–0   SIGNAL n the middle

|–0   GND

 

No photocell, if you put a cable between 24 V and Signal and you see input 1 in the controller screen, you have a PNP input (see also manual)

 

|–0   24 VDC

|–0   SIGNAL in the middle

0       GND

 

Now, you have to know if you have a NPN (sinking) or PNP (sourcing) photocell. Connect the GND to the GND in the gray box, connect the power cable of the photocell to the 24 V in the gray box, connect the signal to SIGNAL. Switching the photocell, you should see the input changing status or you should measure between GND and SIGNAL 0 and 22-24 V.