DOL starting 3 Ph Motor and an RCD

[gerard]

I will double check - sorry about that. I'm pretty sure they are CFW-10 drives, I will check this out.

 

[Specialist]

With reply's like this Im reluctant to post here anymore. Sorry chap PM me if you like.


James

Hi James: Don't really understand what your problem is with the replies gerard has been given, especially Silva's quoted reply. gerard does'nt seem to have a problem with it, so maybe you could explain ?

 

[lewlec]

hi all

been installaing a few abb vsd's and under manufacturers info it specs that if using rcd's they must be of a B type..... 300ma td. unsure if this is the case with other drives but i would imagine that it is because of high earth leakage.

hope this is of use

regards
gary

 

[gerard]

hi all

been installaing a few abb vsd's and under manufacturers info it specs that if using rcd's they must be of a B type..... 300ma td. unsure if this is the case with other drives but i would imagine that it is because of high earth leakage.

hope this is of use

regards
gary

Thanks for that I will order one and give it a go - no harm in trying. I will post my results when I find out

 

[netblindpaul]

lewlec,
Almost certainly due to high earth leakage by design of the drives rather than by any faults though.

 

[lewlec]

lewlec,
Almost certainly due to high earth leakage by design of the drives rather than by any faults though.

yes.... agreed.

 

[silva.foxx]

@ Gerard

Did you try decreasing the switching frequency?

Have you tried taking the VFD out completely?

.

 

[gerard]

No - the frequency has to remain constant for this application. Didn't try taking it out either.
As discussed previously in this section, I think the VFDs might be on the small side - this is not helping the situation either. Will try the 300mA RCD and see how it goes.....

 

[silva.foxx]

No - the frequency has to remain constant for this application. Didn't try taking it out either.
As discussed previously in this section, I think the VFDs might be on the small side - this is not helping the situation either. Will try the 300mA RCD and see how it goes.....

No, not the output frequency... I said the switching frequency.

By taking out the inverter you can find if the RCD still trips, which can point to another issue, perhaps.

Is the inverter good?

Has this machine ran at all since you've had it?

.

 

[gerard]

No, not the output frequency... I said the switching frequency.

By taking out the inverter you can find if the RCD still trips, which can point to another issue, perhaps.

Is the inverter good?

Has this machine ran at all since you've had it?

.

I increased the ramp times to as much as I could. How do you mean take the inverters out - then nothing would happen? The inverters are good except as I said they might be a bit on the small side and at their max in terms of current capabilities. Yes, the machine is running fine with no problems except it's RCDless!