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glock40sw
29th August 2012, 03:16 PM
G'day All.
Went to use the lathe yesterday and all it would do is the chuck would rock backwards and forwards.
It is a 3 phase 3HP pacific.
I pulled the cover off the electrical area and put the test meter on the 3 wires coming in. I have 240Volts at each of the 3 wires.
The contacters for forward and reverse have power to all 3 output connectors.
The strange thing is that the 3 phase coolant pump will not run either.

Other than getting a sparky in to check it out, anyone have any ideas?

Thanks.

Michael G
29th August 2012, 03:38 PM
(With the power disconnected) have you resistance across each of the windings?
If it was single phase I'd suggest the start coil had burnt out, but with 3 phase??

Michael

eskimo
29th August 2012, 05:26 PM
I assume its standard 3 phase

measuring to earth can result in back feed thru windings giving the impression that you have all phases...ideally measure across 3 lots of two phases at the bottom of the contactor...ie
red to blue
blue to white
white to red
each reading should show 415V or there abouts

make sure the motor has equal resistance across all three windings

wbleeker
29th August 2012, 05:39 PM
I had a problem similar to that many years ago on my Takisawa (not sure if it was exactly the same problem) but what caused it was at the headstock end of the forward/reverse/stop lever the cams that work the switches had come loose and weren't doing their job properly, just follow the rod along(if you have one) and where it goes into the headstock base remove the cover and have a look-WITH THE POWER OFF, you will be able to work out if the cams are loose.
Will

glock40sw
29th August 2012, 06:09 PM
The forward reverse rod and cam have 2 limit switches and they are working OK.
It seems strange that the Coolant pump isn't working either.
I might wire the power lead directly to the motor and bypass all the contactors and see if she will spin.

RayG
29th August 2012, 08:34 PM
Sounds like you've lost a phase, and somewhere upstream I'd guess if the coolant pump isn't running either.

Regards
Ray

glock40sw
29th August 2012, 08:53 PM
Thanks, Ray.
A mate is coming to have a look on Friday.

shedhappens
29th August 2012, 09:01 PM
I thing RayG might be on the right track there.

I sometimes have a machine that will just hum when I switch it on and all I do is push the plug into the socket a bit firmer.

eskimo
4th September 2012, 04:43 PM
Sounds like you've lost a phase, and somewhere upstream I'd guess if the coolant pump isn't running either.

Regards
Ray

yep that was what I thought


I wonder what it was? I wish he would report back...!!!

glock40sw
4th September 2012, 06:57 PM
Mate couldn't make it.
The sparky that fitted the new main switch to the meterbox is coming back this Friday to fix his FUBAR...
I'll let you know the outcome.

eskimo
5th September 2012, 08:41 AM
Mate couldn't make it.
The sparky that fitted the new main switch to the meterbox is coming back this Friday to fix his FUBAR...
I'll let you know the outcome.

appreciated...ta

glock40sw......being a SW revolver and STI owner I beleive you need to spend some decent money and get a real gun.....:D :D:D

glock40sw
5th September 2012, 06:51 PM
appreciated...ta

glock40sw......being a SW revolver and STI owner I beleive you need to spend some decent money and get a real gun.....:D :D:D

Ha.... The Kimber and SVI race gun more than make up for the Tupperware. :2tsup:

eskimo
6th September 2012, 08:26 AM
Ha.... The Kimber and SVI race gun more than make up for the Tupperware. :2tsup:

they do indeed....???well I'm not so sure about the Kimber either..but the SVI does

glock40sw
7th September 2012, 11:40 PM
Well. Mystery solved.
The sparky rocked up this morning and looked over everything. When he fitted the new 3 phase main switch, he placed 2 active wires for the shed main switch into the same active connector. Thus I only had 2 active phases in the shed. but when you placed a test light across the 3 actives in the shed it showed that they had power. but when the test light was put from active 1 to active 2 there was no light.
So now the lathe is operational again and turned up a few nylon spacers today.
Life is good with 3 phase.....:2tsup:

Ropetangler
7th September 2012, 11:54 PM
Now that should be worth some discount for all the inconvenience he caused, and the lost time etc.:rolleyes: I'm glad that's all it was though.:)
Rob.

Machtool
7th September 2012, 11:58 PM
The sparky rocked up this morning and looked over everything. When he fitted the new 3 phase main switch, he placed 2 active wires for the shed main switch into the same active connector. Thus I only had 2 active phases in the shed.:
Are you happy about that? Seems to me, any sparky I've every known, would have had his gonads grow back in, if he didn't know where a phase was going too.

glock40sw
8th September 2012, 08:33 AM
Yeah. It was no charge for yesterday fixing his error. And they are going to re-imburse me for the $92 it cost for the air con bloke to come out and "fix" the problem of the compressor running backwards too...

eskimo
9th September 2012, 12:45 PM
Well. Mystery solved.
The sparky rocked up this morning and looked over everything. When he fitted the new 3 phase main switch, he placed 2 active wires for the shed main switch into the same active connector. Thus I only had 2 active phases in the shed. but when you placed a test light across the 3 actives in the shed it showed that they had power. but when the test light was put from active 1 to active 2 there was no light.
So now the lathe is operational again and turned up a few nylon spacers today.
Life is good with 3 phase.....:2tsup:

as I said above...if you had measured between phases and not to earth it would have been revealed that something was amiss
only 2 phases eg red to yellow and blue to red would have read 415V

blue to yellow would have been 0 V...but reading all phases to an earth contact would have shown 240V on the meter