What are you doing as trainees?

[Bobster]

Yeah im ok with that, I take it the latching contact at k1.4 provides No volt release?

The contact marked K1.4 is the main motor contactor, it's what's used to latch the circuit once the pushbutton is pressed.

I cant see whats missing at the PSU either, a fuse maybe?

Your right with a fuse, primary protection is definitely needed (240V side), and most power supplies over a certain size will need a secondary fuse.(24VDC side)

Make sense?

 

[pennychew]

Yeah that makes sense, i did have a little mess about with a contactor a while ago and managed to get a no volt release system working with a non latching contact. It was on my test rig thread, i'll post a link but not sure it will work....

http://www.electriciansforums.co.uk/electrical-course-trainees-only/84211-test-rig.html


I did buy some telemecanique buttons and drilled some ali plate to make some controls but never got round to it.

Really interested in this area, I've just been to see a guy I know who does automation projects and is an agent for Mitsubishi doing PLC stuff. He's going to take me on some of his jobs with him after xmas if i can free some time up

 

[ElectroChem]

When I called K1.4 a latching contact I only meant in the sense of holding the contactor in so you don't have to hold the start button. The contact will pull out if the coil loses voltage as you said.

Rob yes we would normally put a breaker for the 240 and 24v sides of the PSU

 

[alanmcm]

learning to wind motors, in northern ireland. Been at it for two months now after training to look after sewage stations.