Negative vs Positive DC Inputs
Negative vs Positive DC Inputs
(OP)
I have tried to explain DC negative vs positive inputs to a bunch of sales guys. Let's just say I have not been very succesful. Does anyone know of a site that has some elementary information that I can send them to or some info I could use to help get this across.





RE: Negative vs Positive DC Inputs
This appears so totally obvious and transparent, (like 4th grade science), that we are not going to be able to help you without more input.
Please try with us again. What is this all for? Maybe that will help us - help you.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Negative vs Positive DC Inputs
Keep it simple...
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Negative vs Positive DC Inputs
I was hoping someone knew of some material or site that had information I could send them to. I know its simple but instruction was never my strong point.
RE: Negative vs Positive DC Inputs
http://ww
The diagrams are pretty clear.
Others like:
http://www.patchn.com/npnpnp.htm.
xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
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RE: Negative vs Positive DC Inputs
RE: Negative vs Positive DC Inputs
Then you had to use sinking inputs. The result of this was that if you ever troubleshoot an input that is triggered by providing a common through the card. It is very hard to troubleshoot since your looking for a dc common.
Most plc manufacturers do not provide off the shelf sinking cards. Usually its a long lead time.
RE: Negative vs Positive DC Inputs
It's not just as simple as sinking vs sourcing, occasionally you get an output that goes negative in relation to ground e.g. 0 = 0V, 1 = -12V
Sales guys eyes glaze over, if ever you try to talk about something they don't sell, they just want to move their product, they don't really care about your problems.
Roy