Question on 24VDC Honeywell DI card

[notredave68]

All,

Can someone tell me if I have wired up N.O. contact correctly on attached PDF? Does +24vdc land on common terminal or NO terminal? Does it matter on a dry contact? Any links or explanations on this matter would be appreciated.

Thanks in advance,
David

Thanks in advance,
David

 

[danw2]

Your subject says DI which by convention means digital input.

However, common and a N.O contacts are associated with a digital output.

With just terminal numbers It is not clear what deice you are working with.

If a DI needs a dry contact, then you do not connect a voltage to either terminal. You connect dry, un-wetted contacts, like relay contacts.

If the binary signal is powered, drive a relay coil with the signal and wire the relay's dry contacts to the DI.

If your terminals are a digital output, an electromechanical relay's contacts, which if labeled Com and NO they most likely are, then voltage is typically wired to the common, load to the NO.

 

[danw2]

I got stuck on a webinar and had time to look at the diagram. The alarm output appears to be dry contacts and the card is a DI, although the polarity of its power supply markings appear to be backwards.

The connection between the DI and the alarm is OK. The DI will work wired to either alarm contact terminal.

 

[notredave68]

danw2, thank you very much for your input, I appreciate it!

Thanks in advance,
David