Micrologix 1400

[[email protected]]

So I should use an rc type terminal block in conjunction with my din cable that it suppose to already have surge suppresion (varistor) built in?

 

[James Mcquade]

[email protected],

Before answering, what is your wiring setup?
How do you go from the output card of the plc to the final device?

james

 

[[email protected]]

I go straight from the relay output of the micrologix 1000 to the solenoid(0.69 amp on the coil rating to be exact) using the 889V-LA2DBE-5 (AB varistor surge supressor din valve cable rated for 120 vac). So I am surge supressing at the valve with the built in din connector. Havent had the problem since I put the Isolation relay in yet, but it arcs like crazy so I know its a matter of time. Is it maybe something to do with the "varistor" surge suppression? I need to get rid of the arc somehow when im shutting off the relay

 

[James Mcquade]

[email protected]

My surge protection is built into my AB din cables (889V-LA2DBE-5). I did add dry contact relays in between and now i can actually see the arc when they shut off... Maybe I recieved the wrong cables? I did not check that...

If I understand your post is your post, from your output card you are going to the solenoid output using a cable with built in suppression.

if this correct, You have now added a relay between the output and the solenoid.
So what you have now is put the surge suppression cable on the relay coil and the solenoid is being powered by the relay contacts with no surge suppression.
The arc you are seeing is due to the contacts opening and the fact that the relay contacts are most likely not rated to handle the extinguishing arc.
I would put suppression on the solenoid and also check the contact ratings of the relay in use. The break current can be 4-6 times larger than the make current.

james