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Coil voltage on open relay contacts ?

Open rolox2022 opened this issue 1 year ago • 2 comments

Hi, i noticed a strange behaviour: there seems to be some "interconnection" between coil and contacts of a relay .... can be reproduced with simple circuit attached. relay issue relay issue.txt

rolox2022 avatar Feb 07 '24 17:02 rolox2022

Edit...its obviously a misunderstanding on my side...the parameter "off resistance" is by default 1M which affects low current signals switched by relay and also is related to contact-contact resistance as kind of "isolation resistance" As in the example no current is applicable with only testpoints, the full 5V show up at the open contacts ....

rolox2022 avatar Feb 11 '24 10:02 rolox2022

Yes, that's correct. You need a pulldown resistor if you want the open contact to be grounded.

pfalstad avatar Feb 11 '24 19:02 pfalstad