Star Delta Motor Running Trouble

hi, what is that thing which is tripping? is the main breaker or is it the overload relay?, what is the rating amps of the breaker and or the overload? was it working right before? or you just did this circuit newly? what is the load which that 55kw motor driving? can you give me copy of the circuit diagram of your project?

i need more informations so i can help

Asking the same vague, ill-specified question in two different threads does not improve you chances of getting a useful response.

If you were to re-phrase your question, giving the information that you have been asked for, then some help might be possible.

Please try again.

Hi Enkays,

I agree with the other posters who say that your post is so vague and devoid of information that it's difficult to work out what your problem might be. Add to this the incorrect terminology - each component of this starter appears to be 'tripping'?

So far you seem to be using new part fitters in an attempt to clear the fault and I would seriously suggest that it would be more expedient and cost effective (not to mention safer) to employ the services of a qualified and experienced electrician.

A problem like this is normally sorted out by operating the starter in a 'dry run' condition where the operation of the starter plus timing of the changeover can be observed without the danger of high inrush and transient currents from the main circuit.

Seeing as Star/Delta starters (closed or open transition) have only a few possibilitys of control circuits a 'real' electrician would sort the problem out quickly even without drawings.

As far as the main circuit is concerned the main supply and the cabling to the motor may be easily checked and proved with a multimeter. The motor itself can be tested with an insulation tester (Meggered).

But there again, all the above information is absolutely useless if one doesn't understand what the term 'trip' refers to!

Hope the above is of assistance to you but perhaps if you try posting on a few other threads you may get more information..