adccommunitymod (AutomationDirect) asked a question.
Created Date: May 28,2014
Created By: bsmith
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I am new to PLC programming and just bought a Click C0-02DD1-D coupled with a C0-01AC power supply. My first program is just to use a few of the digital inputs on the unit to control a pump motor going on and off in reaction to a pair of upper and lower float switches tied to x001 and x002 My first thought is that the unit would default to a sinking input mode with 24v on C1. Yet in mocking up the scenario on a bench there is no voltage on C1 or any of the input terminals in case the unit were in source mode for some reason. But then I realized that I don't even know how to change the source or sinking mode of the digital inputs. The PLC unit communicates with my computer fine and I believe I have everything setup and configured properly, but what am I missing here?
Created Date: May 28,2014
Created by: bcarlton
Read the manual. The diagram for your unit in section two clearly shows both methods of wiring (there are no switches) by the polarity of the external supply voltage.
Created Date: May 28,2014
Created by: winterrossi
You have to supply the power to the input module from the power supply by wiring it. Sinking or sourcing depends on whether you supply + or- to the common terminals.
Created Date: May 28,2014
Created by: bsmith
Read the manual. The diagram for your unit in section two clearly shows both methods of wiring (there are no switches) by the polarity of the external supply voltage.
"You have to supply the power to the input module from the power supply by wiring it. Sinking or sourcing depends on whether you supply + or- to the common terminals. "
I see this now. I think I was influenced by my experience with VFD's that can supply their own 24v for sourcing or sinking inputs with a jumper setting. Since the PLC unit itself already had 24v running through it, I mistakenly thought it could make C1 and C2 a 24 volt source. But I see now that 24v has to be wired externally to the inputs, and not just for add-on input modules but also for inputs on the Click PLC itself. Thanks to both of you for your comments on this.
Created Date: May 28,2014
Created by: bsmith
I am new to PLC programming and just bought a Click C0-02DD1-D coupled with a C0-01AC power supply. My first program is just to use a few of the digital inputs on the unit to control a pump motor going on and off in reaction to a pair of upper and lower float switches tied to x001 and x002
My first thought is that the unit would default to a sinking input mode with 24v on C1. Yet in mocking up the scenario on a bench there is no voltage on C1 or any of the input terminals in case the unit were in source mode for some reason. But then I realized that I don't even know how to change the source or sinking mode of the digital inputs.
The PLC unit communicates with my computer fine and I believe I have everything setup and configured properly, but what am I missing here?