Spindle ON trips GFCI/RCD/RCCB immediately.
Hi all,
Just moved to a new property, with a GFCI installed (RCD or RCCB here in Europe). This one specifically: Crabtree 63A 30mA Manufacturer's Part Number: RS/363/S030.
It trips as soon as the spindle is turned on.
Tormach's user manual suggests that the spindle VFD is the issue. It recommends against the use of a GFCI. Page 181, item 10.5.4.
Is there an alternative GFCI available which will work with the VFD? Or will I have to simply remove it and accept the risks involved with doing so?
Or is there a better solution?
Any help you can offer would be greatly appreciated. I didn't anticipate this before moving here, so now I'm in a bit of a panic.
Thanks,
Lee
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Hi Lee
you may need to have a 100mA RCCD installed to supply your machine
keeping the existing 30mA RCCD for your domestic supply
a good electrician should be able to help you
select a RCCD with the correct sensitivity
and possibly the MBC
John
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Thanks very much for the fast reply John!
Just realised, I didn't mention that my machine is a Tormach PCNC 1100.
I was hoping to buy the part I need and fit it myself, rather than use an electrician. I thought that the correct rating would be known by Tormach, or other users. Would an electrician be able to do some testing to determine the correct mA rating for the RCCD?
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
I can think of three possible reasons the RCCB trips when the spindle is switched on -
1 , the mains filter fitted to the machine to get CE approval , has capacitor between live and earth resulting in a leakage current
when added to the leakage currents of all the other filters in devices connected to your supply adds up to more than 30mA
( for example they will be in computer power supplies ,monitors , TV's , set top boxes , satellite receivers and washing machines )
2, a small leakage current between the motor windings and the motor frame
3, the VFD could have leakage currents due to its own internal main filter circuit
since you don't want to have another RCCB fitted , as a test I'd try bypassing the machines mains filter
it could be enough to let you start the spindle depending how close to the 30mA limit you are
if that didn't work , a second test with as many devices ,with switch mode power supplies, in the house you can switch off at the socket or unplug ( too many things like your PC and TV don't have a real on/off switch)
depending on the result you may have to have changes made to the supply to the work shop
ideally you need an electrician with experience in industry not one with the minimal qualifications for domestic wiring
I guess the easy way will be to by connect the Tormach PCNC 1100 without the RCCB and measure the leakage or
try a 100mA RCCB and if necessary a 300mA RCCB - some thing you can't do without the correct bit of paper
an office with a large number of PC's can have the same problem with the earth leakage current being over 30mA
John
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
It is extremely common for VFD to trip GFCI. Not a malfunction, just the price of admission.
My solution is to swap out the GFCI for a normal plug, but that is a code violation (at least in the states).
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Its almost certainly option 1. Does your machine have CE approval?
My understanding of circuit breakers (which may very well be wrong) is that they are guaranteed to trip at no higher than the specified current. That means that they can trigger at significantly lower levels, and recent measurements in my house would also confirm this. My PCNC 1100 will run from some outlets but not others - all are 30mA. Try a different outlet!
If that doesn't work check under the VFD and you'll find a small tab. Pull it down and it will disconnect the filter. I simply added another filter next to the breaking resistor - it may not be as good as the built in filter but I wouldn't recommend using the machine without one, and certainly not without some form of GFCI
Step
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
If you have the Emmerson VFD controller then there is a jumper you can remove that will stop it from tripping the RCD. The manual for the controller is online and it tells you about this. It worked for me and I run with an RCD with no trips when the spindle starts. Let me know if you need more help and I will try and find my manual and look it up.
Dave.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
TurboStep
...I wouldn't recommend using the machine without one, and certainly not without some form of GFCI
From the US standpoint, there is no requirement for GFCI on 240V circuits. I am betting that every single 1100 owner on this board in the US is operating their Tormach 1100 off a 240V circuit with no GFCI, and not missing it. Since the 240V outlets we use have no neutral connection, GFCI would be of limited value.
Different country, different code. The OP is UK, you are Switzerland, you both have different rules.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Tim
Quote:
Originally Posted by
tmarks11
From the US standpoint, there is no requirement for GFCI on 240V circuits. I am betting that every single 1100 owner on this board in the US is operating their Tormach 1100 off a 240V circuit with no GFCI, and not missing it.
The GFCI is there for your safety. You may never miss it, but your family may miss YOU if you don't use one !!!
Quote:
Originally Posted by
tmarks11
Since the 240V outlets we use have no neutral connection, GFCI would be of limited value.
You may need to read this:
http://www.nema.org/Products/Documen...esentation.pdf
Check out page 21 "240 Volt Load – No Neutral".
Quote:
Originally Posted by
tmarks11
Different country, different code. The OP is UK, you are Switzerland, you both have different rules.
The OP appears to be in the UK and I'm in Switzerland - correct. Unfortunately EU regulations apply to BOTH countries (I can't rule out minor deviations). Your sig. says United States. Very different countries - very different rules perhaps? :)
Oh, just one thing, I may be in Switzerland but I just happen to be BRITISH :) :)
Step
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
TurboStep
Its almost certainly option 1. Does your machine have CE approval?
My understanding of circuit breakers (which may very well be wrong) is that they are guaranteed to trip at no higher than the specified current. That means that they can trigger at significantly lower levels, and recent measurements in my house would also confirm this. My PCNC 1100 will run from some outlets but not others - all are 30mA. Try a different outlet!
If that doesn't work check under the VFD and you'll find a small tab. Pull it down and it will disconnect the filter. I simply added another filter next to the breaking resistor - it may not be as good as the built in filter but I wouldn't recommend using the machine without one, and certainly not without some form of GFCI
Step
the tripping of a circuit breaker has to do with a few different scenarios and totally depends on the trip curve of the breaker, read this http://static.schneider-electric.us/...0600DB0105.pdf
A breaker that is not a GFCI, will never trip below its rated current!
A GFCI breaker is a diffrent beast again, where the current between neutral and ground is monitored should it exceed the rating of the GFCI the breaker will trip. Should the ground be compromised the breaker will trip. should it be wired wrong, the breaker will trip. They are quite fantastic actually. In north american, no 220v piece of equipment will run on a GFCI breaker for the simple reason that there is no neutral to monitor, its our beautiful split phase system. The only way you could use a gfci at that point an time is to have a neutral going there too, like a hot tub.
on safety, GFCI's have been designed where water can come into contact with electricity like bathrooms, hot tub, outside plugins, etc. In a case where there is a gfci installed as a mains breaker this can give some difficulties, as mentioned VFD's and GFCI's do not get along (and they are not the only thing). While it is probably cheaper to install a GFCI for the whole house it is some short sighted as it can cause problems.
if you were to remove the ground from your mill you'll notice it will probably run just fine. however this is not a solution.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Thanks everyone for your input! Lots of helpful info here. Way more useful than Tormach themselves have been.
Quote:
Originally Posted by
davebaldwin
If you have the Emmerson VFD controller then there is a jumper you can remove that will stop it from tripping the RCD. The manual for the controller is online and it tells you about this. It worked for me and I run with an RCD with no trips when the spindle starts. Let me know if you need more help and I will try and find my manual and look it up.
Dave.
I do have an Emerson VFD, so this sounds promising, and certainly the easiest solution. Are there any drawbacks?
I believe I've found the correct manual but I'm having trouble locating the part you're referring to.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
RCCB = residual-current circuit breaker, where as RCBO = residual-current circuit breaker with overcurrent protection.
The OP appears to have a "Crabtree 2 Pole Residual Current Circuit Breaker".
Quote:
Originally Posted by
xjdubber
.. A GFCI breaker is a diffrent beast again, where the current between neutral and ground is monitored should it exceed the rating of the GFCI the breaker will trip. ... no 220v piece of equipment will run on a GFCI breaker for the simple reason that there is no neutral to monitor
I think you need to read up! Check out page 21 of the document I linked to in my last post.
Quote:
Originally Posted by
xjdubber
if you were to remove the ground from your mill you'll notice it will probably run just fine. however this is not a solution.
Don't ever, EVER even remotely hint to anyone that they should remove the ground from any electrical device! In the case in question the Tormach does not have the insulation required to be operated without a ground, not by a LONG way!
Step
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
TurboStep
No kidding.
My point remains. In the US, there is no code requirement for GFCI on 240V outlets. Good thing, too, since a GFCI breaker runs about $80, and I would need 5 of them in my garage.
Every one with a Tormach 1100 in the US is plugged into a 240V receptacle without a GFCI. So we never experience the problem the OP is facing. 770 is a different story, since it is plugged into 120V, and (by code) garages must have GFCI on their outlets.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
TurboStep
I think you need to read up! Check out page 21 of the document I linked to in my last post.
Don't ever, EVER even remotely hint to anyone that they should remove the ground from any electrical device! In the case in question the Tormach does not have the insulation required to be operated without a ground, not by a LONG way!
Step
Yes you are right, you can use a GFCI with a 220v load on a split phase circuit, however if the use of it is not in a wet environment it does not help you at all, however saying that I realize these machines use flood cooling and there could be be issues with that. Also realize that a gfci could trip just because of the coolant pump, especially if it is a submersible. If they leak even a tiny little bit there will be enough conductance from line to ground or neutral to set it off.
Never did I suggest that removing the ground was a solution, however as a means of testing it can be done, so that you can isolate the issue to a gfci.
my advice would be to look at your local electrical regulations, no matter what NEMA, or UL, Or CSA, or CE says, your local electrical regulations are above that.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
tmarks11
My point remains. In the US, there is no code requirement for GFCI on 240V outlets. Good thing, too, since a GFCI breaker runs about $80, and I would need 5 of them in my garage.
US and EU (including Swiss) regulations apparently differ in this respect. Wikipedia:
The current edition (17th) of the [UK] regulations requires that all socket outlets in most domestic installations have RCD protection, though there are exemptions... The new requirements for RCDs do not affect most existing installations unless they are rewired, the distribution board is changed, a new circuit is installed, or alterations are made such as additional socket outlets or new cables buried in walls.
Quote:
Originally Posted by
tmarks11
Every one with a Tormach 1100 in the US is plugged into a 240V receptacle without a GFCI. So we never experience the problem the OP is facing. 770 is a different story, since it is plugged into 120V, and (by code) garages must have GFCI on their outlets.
I've no idea what the common practice is in the US for 240V but I personally wouldn't want to use any machine, particularly a machine made entirely of metal, without come kind of earth leakage protection. I now have 3 RCBOs feeding my workshop. One of them is 3 phase and protects 400V 3 phase equipment without a connection to neutral. I haven't always been so careful but I've had my fair share of shocks in the past and I know how easily it can happen. It not only makes good sense IMHO but if anything does happen the insurance companies would be more than happy to use their omission as a reason not to pay up!
Different countries, different customs....
Step
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
hmm intertesting, i've been doing industrial control panels, and electrical troubleshooting on machinery for close to 15 years now. I've been shocked twice, once changing a light bulb and another time working on a outlet underneath a desk live. both times where is should have turned the power off......
I work out of a manufacturing plant where there is no use of GFCI's whatsoever, have not heard of anybody getting electrocuted yet. Don't count on a GFCI saving your bacon, ive seen them fail where the only way they trip is on an over-current situation. Best way to avoid electrical issues is to wire equipment properly.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
TurboStep
I now have 3 RCBOs feeding my workshop.
Would you be able to recommend a suitable one for a Tormach PCNC 1100?
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
Eli_Ben
Would you be able to recommend a suitable one for a Tormach PCNC 1100?
I PM'd you.
Step
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
Eli_Ben
Thanks everyone for your input! Lots of helpful info here. Way more useful than Tormach themselves have been.
I do have an Emerson VFD, so this sounds promising, and certainly the easiest solution. Are there any drawbacks?
I believe I've
found the correct manual but I'm having trouble locating the part you're referring to.
https://www.inverterdrive.com/file/C...al-Manual-Data
page 79.
Dave.
Re: Spindle ON trips GFCI/RCD/RCCB immediately.
Quote:
Originally Posted by
davebaldwin
Thank you! I will try this shortly!
Interestingly, that page states that the ground leakage current is 28mA - extremely close to the 30mA sensitivity of the RCCB installed in my fuse box!