PNP Output Problem

Hi folks,

I have PNP output problem at Ge Fanuc RX3i Digital Output Module,

the d. output always have some voltage ( 7 vlotage ) when the CPU

was given energizes command.

My Digital input are assign NPN type and Digital Output also NPN.

there are share same power supply!.

so how to do the grounding work on the power supply????




regards

It would probably be helpful if you could make a sketch of your wiring, save it as a bmp or jpg file, and post it here. Please include the part numbers of the modules you are using.

GE Fanuc tends to avoid the terms "PNP" and "NPN" when describing their discrete I/O modules. Instead, they use the terms "Positive Logic" and "Negative Logic".

hi, here is digital output diagram ..

no it's not...

this model is ic694 mdl752

Your wiring appears OK. At least it seems to agree with the diagram in the manual GFK-2314B.

What exactly is the problem? Does the field device not energize when logic turns the output circuit on? Does the field device remain energized after logic turns the output off? Between which two terminals are you measuring 7 volts? Did you purchase pre-made cables or make your own?

Your drawing shows a dashed line connecting pin pairs 8 and pin pairs 5. That's just the way the manual shows it. Did you make the connection at the terminal strip?

output point remain on when plc denergized. that around 6 ~7 volt, ( sometime ) at q00073 / kv442 ! we have no make the link between pin 5 and 8..

any solution ?

What is the device KV442? What are its specifications? How much current does it draw? How much leakage can it take without actuating?

The output on the MDL752 is rated for 0.5 amps at 24 VDC. And its leakage current is listed as 0.1 A maximum.

I'm afraid I don't understand your statement "output point remain on when plc denergized. that around 6 ~7 volt". When the logic turns the output off, you should measure 24 VDC between terminals X13/9 and X13/20. When the output is turned on, the voltage should drop to some low level. Between which two terminals are you measuring 6 - 7 volts?

kv442 actually is a relay (omron - 2 pole 24vdc) this current draw by this relay should around 0.2Amp .

When the logic off and i measured terminal x13/9 and x13/19 i get 6 ~7volt !

when i measure x13/20 i can get 20 ohm and the reading was floating.

yup i purchase the pre made connector ( fujitsu ).

Measuring between X13/9 and X13/19 is measuring the voltage drop across the relay coil.

Do any of the outputs work properly? If so, measure their voltages and compare your measurements to the output point that does not work.

yup the other points was work properly, especially all points on the left hand diagram. the diferrent voltage was 0.1amp.

i have 5 this type of module, i notice that only the points of the right diagram have this proble ! some i measured was 0.9 amp. ??

If you compare your diagram to the one in the manual I cited, you will notice that in the manual, the pins for the right hand connector are numbered from 1 to 12 (top to bottom) while yours are numbered from 12 to 1. It looks like this shouldn't make any difference in your application, bit If I were you, I would double-check the wiring.

Also, I think you need to make that connection between the two pins numbered 5 and the two pins numbered 8 in each connector. You will have to do that at the terminals. The connection is not made in the cable nor in the module.

I think the reason they show the connection as a dashed line is because for a sourcing output module you connect two different pairs of pins together and they use the same cable for both types of module. It would be nice if the manual included a note to that effect.