Author Topic: No, No this could be expensive!  (Read 13939 times)

Offline Jo

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No, No this could be expensive!
« on: November 10, 2013, 11:30:06 AM »
This morning I started japanning out the flywheel for the Double Tangye, when the Colchester started making funny noises "down below". I started by trying to check without the guard on but she was having none of that. I couldn't get the motor inspection plate off  so I took the contactor plate off nothing obvious. So having used my lady like muscles I have dragged the lathe out:



Then took the motor cover plate off:



The motor is hot, and when I run her the motor sounds like a bag of bones.  :facepalm2: Time to take the motor out and have a look.

Jo
« Last Edit: November 10, 2013, 12:00:27 PM by Jo »
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Offline sshire

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Re: No, No this could be expensive!
« Reply #1 on: November 10, 2013, 11:37:25 AM »
Jo
Noooooo! Sorry to hear of your malfunction.
Bad bearings? If that's it, a decent motor shop can get you up an running quickly and for a reasonable price. If the rotor is smacking the stator and has bunged that up, a new motor might be in your future. Hope not. But, if so, think about a VFD. I've got them on the lathe and on the Bridgeport and would never go back.
Fingers crossed.
Best,
Stan

Offline Jo

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Re: No, No this could be expensive!
« Reply #2 on: November 10, 2013, 11:59:52 AM »
Thanks Stan,

I have hooked the motor out and sat her on the floor and run her she doesn't sound 100% but is still trundling ok. I've whipped the back off she looks to be wired in star:



Ok I don't normally have a good word to say about he who hath gone   :hellno: but he claimed to have found a 2 speed motor for the colchester all those years  :old: ago.



Well he wasn't much of an electrician I've just read the label it is the same speed/rating of motor as is fitted  :lolb:. Maybe that was why he didn't fit it like he promised he was going to  :naughty:

Jo

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Offline Don1966

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Re: No, No this could be expensive!
« Reply #3 on: November 10, 2013, 12:09:46 PM »
Jo, is your motor dual voltage? Looking at your connection it should be Delta, us less specified otherwise. If someone you know has an amp meter, have him amp check the motor. Even if the amps are higher than the name part value as long as all three legs  read the same value means the motor is good. Then your bearing could be bad. Bad bearings causes a good rumble in the motor.

Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #4 on: November 10, 2013, 12:14:05 PM »
Thanks Don  :ThumbsUp:, Its the hot electrical smell that is worrying me.

Short term I am planning on swapping the motor over with that new one I have found, it says Student/Master in pen on it so I am assuming it was the college's spare motor for these machines  :).

Then after I have done the flywheel I might take this one apart. Interstingly both have their card instruction books in the electical box. 

Jo
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Offline Don1966

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Re: No, No this could be expensive!
« Reply #5 on: November 10, 2013, 12:20:07 PM »
Jo, if you swap motors please amp check it or you could end up burning it. Amp checking a motor will tell you if it's miss connected or you have loss a three phase leg.

Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #6 on: November 10, 2013, 12:22:37 PM »
What do you mean by lossed a three phase leg? Are you thinking that one of the contactors might not be making? I use the same three phase converter on the harrison.

I just turned on the Harrison.. She is making funny noises. So it is now pointing towards the transwave unit...

Jo
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Offline Don1966

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Re: No, No this could be expensive!
« Reply #7 on: November 10, 2013, 12:32:19 PM »
Yes! If all possible have someone amp test it. Or check for loose connection.

Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #8 on: November 10, 2013, 12:41:20 PM »
I'll keep my fingers crossed for a loose connection.. about to lift the transwave's lid  :(.

Jo
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Offline Jo

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Re: No, No this could be expensive!
« Reply #9 on: November 10, 2013, 12:59:46 PM »
The lid is off the transwave (3 phase converter) and there is nothing obvious:







The contactor for the boast seems to be working when the machines start up but the current is remaining high as if it is still trying to start on two phases and the third hasn't formed.

For some reason I am not enthusiastic about getting my hands in there with the power on.

Jo
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Offline Don1966

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Re: No, No this could be expensive!
« Reply #10 on: November 10, 2013, 01:14:44 PM »
Jo, from what you are saying it is obvious that you have loss a phase. I think you need to get a professional to look at it. Best be safe electricity is not to forgiving.

Don

Offline steamer

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Re: No, No this could be expensive!
« Reply #11 on: November 10, 2013, 01:43:55 PM »
Wot Don said!.....I'd stop right there Jo.

Dave
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Offline Jo

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Re: No, No this could be expensive!
« Reply #12 on: November 10, 2013, 01:58:32 PM »
I did 4 years as an Electrical/electronics Apprentice and then worked on 600V DC equipment for about a year. So I am under no illusions about the dangers of electrics.

I'll contact MSR in the morning..

Jo
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Offline steamer

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Re: No, No this could be expensive!
« Reply #13 on: November 10, 2013, 03:00:01 PM »
No such illusions, or lack of understanding Jo was not what prompted my comments Jo....I know you know your stuff...........but lack of proper measurement equipment to hand was my angle.   These guys have the right tool for the job......you know how important it is to have the right tool and know how to use it right? 8)

Dave

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Offline steamer

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Re: No, No this could be expensive!
« Reply #14 on: November 10, 2013, 03:02:45 PM »
My Logan really didn't like the static phase converter, and it would get hot and trip the heaters in the breaker fairly quickly,   I then added an idler motor to the circuit and basically made a RPC.  It is much happier with that...though If I am putting the beans to him for a while, I can still trip the breaker.

Dave
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Damned ijjit!

fcheslop

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Re: No, No this could be expensive!
« Reply #15 on: November 10, 2013, 05:04:10 PM »
Hi Jo, the maintenance guys should have a clamp meter it maybe a different matter prizing it out of there hands.
cheers

Offline Jo

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Re: No, No this could be expensive!
« Reply #16 on: November 10, 2013, 05:13:39 PM »
 :thinking: I have a clamp meter on my mains input for monitoring my power uasge.

Thanks Frazer  :ThumbsUp:

Jo
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Online sco

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Re: No, No this could be expensive!
« Reply #17 on: November 10, 2013, 08:16:19 PM »
So is the conclusion the lathe motor is fine and it's the box of tricks supplying three phase to the work shop that's on the fritz?

Simon.
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Offline Jo

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Re: No, No this could be expensive!
« Reply #18 on: November 10, 2013, 08:54:20 PM »
Yup, Hope to fix the three phase converter.. worse case buy another one  :(.

Jo
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Offline zeeprogrammer

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Re: No, No this could be expensive!
« Reply #19 on: November 10, 2013, 10:48:27 PM »
I hope you get things sorted out quickly Jo.

In the meantime I got stumped by this...

This morning I started japanning out the flywheel for the...

What is japanning?

Thanks
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Offline sshire

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Re: No, No this could be expensive!
« Reply #20 on: November 10, 2013, 10:50:00 PM »
An ancient Asian variation of trepanning?
Best,
Stan

Offline Jasonb

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Re: No, No this could be expensive!
« Reply #21 on: November 11, 2013, 07:33:27 AM »
Thats when Jo lacquers the rust black ;)

Offline Jo

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Re: No, No this could be expensive!
« Reply #22 on: November 11, 2013, 07:49:00 AM »
 :lolb: that's what happens when you are stressed out and all you can see is the moths trying to escape your purse.

Someone mentioned the idea of replacing this static converter with a VFD. Big no, no: VFDs are ok for machines with only one motor, such as the headstock of a lathe but this converter runs a total of 6 motors: 2 on the Colchester, 3 on the Harrison and my cutter grinder.

Just over another hour to find out the damage to the purse  :(

Jo
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Offline Stuart

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Re: No, No this could be expensive!
« Reply #23 on: November 11, 2013, 08:06:34 AM »
Jo

I would hazard a guess is the one are more of the caps have failed giving you two and a half phases else the motor would not have turned just hummed

My gut feeling is that a manufacture repair will get pricey PDQ

those moths will be happy to get out and fly about  >:D

hope you get it sorted

got our own problems to sort today NWB in there wisdom not have deemed our gold cards have been compromised and stopped both of they and changed the Acct. No. ( just after a purchase of a 5s , then because of that Linda had to use her visa card for the online shopping order guess what that did a wobbly and Nat west then blocked that one because I was in the room when Linda was talking to them , ( heck they are both joint Accts. ) so we are down to one plastic  :censored: :censored: :censored:

to top it all its Linda's XX ( dare not post it but she has had a bus pass for 7 years ) birthday today no chance of forgetting the date is there 11/11/xx


please let the collective know the out come of your  :zap: problem , it helps with the hives knowledge pool

Stuart 
My aim is for a accurate part with a good finish

Offline swilliams

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Re: No, No this could be expensive!
« Reply #24 on: November 11, 2013, 08:15:58 AM »
Quote
This morning I started japanning out the flywheel for the...

What is japanning?

Thanks

japanning was a hard black finishing process in lieu of paint. Not to be confused with trepanning of course  :Lol:

Jo, this magic transwave box thing is pretty cool. Hope it doesn't end up making too big a hole in your pocket  :o

Steve

Offline Jo

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Re: No, No this could be expensive!
« Reply #25 on: November 11, 2013, 08:18:40 AM »
Thanks Stuart... I have been going over the history of this unit.. I paid £100 for it in about 1993, 20 years good service so I really can't complain.

Half of me is resigned to buying a new one and then seeing if I can get the old one fixed. That way I would have a spare converter for one of those other milling machines I see in my future  >:D

Jo

P.S. Sympathies on the cards... I took out a second credit card and always use that for food/fuel after I had mine first one hacked in London.
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Offline Stuart

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Re: No, No this could be expensive!
« Reply #26 on: November 11, 2013, 08:31:00 AM »
Jo

Its going to get spendy PDQ by the look of it at least you get a 3 year GT  better get those moths fed up well


http://www.powercaps.co.uk/wp-content/uploads/2013/06/2011-TRANSWAVE-Prices-STC-MT-RT.pdf

not sure how much pongo you need tho for your multi machine set up I assume you transfer the machine by means of the plug/skt else the size of the unit would be quite big and require a large supply rail

I had to do a double take on the colour of the wiring to the motor two red and one black made me blink

Stuart
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Offline Jo

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Re: No, No this could be expensive!
« Reply #27 on: November 11, 2013, 08:51:52 AM »
Stuart: I have wired all three of the machines into a single 16A 3 phase plug which goes into the front of the transwave to avoid all the messing around with plugging/unplugging all the time.

That is the original Colchester wiring.. Haven't touched it, hopefully won't have to.

I thought I had found a cheaper supplier of these units then realised that the other company had not mentioned "plus VAT"  >:(.

Jo
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Offline Jo

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Re: No, No this could be expensive!
« Reply #28 on: November 11, 2013, 09:35:16 AM »
I have just spoken to the very, very, very nice man (Peter Moss) at Transwave and he could describe the fault to a Tee. He is laying bets it is the Contactor which is going to cost me £27 inc Vat & P&P. :whoohoo:

But it is not all plain sailing as the new contactors are much bigger than the old ones  :-\ so when it arrives on Friday I will have to do some metal bashing and it is important that the contactor goes the right way up with the wires top and bottom.

He also identified that my unit was made in March/April 1984, so she has paid for herself over and over. I also discovered that the unit I have is not the cheap one but the high powered one (necessary for high torque starts, like the colchester on high speed) which if I chose to replace it is £432.

Jo
---
(Busy cramming the moths back into my purse  ;))

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Online sco

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Re: No, No this could be expensive!
« Reply #29 on: November 11, 2013, 09:39:07 AM »
Good news then, no reason not to spend the money you've saved on some more castings then  ;D

Simon.
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Offline Jo

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Re: No, No this could be expensive!
« Reply #30 on: November 11, 2013, 10:10:49 AM »
 :o

Another man trying to encourage me to spend money on desirable things, it is very difficult but I am trying to be a good girl. :embarassed:

Jo
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Offline b.lindsey

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Re: No, No this could be expensive!
« Reply #31 on: November 11, 2013, 12:04:22 PM »
Jo, with absolutely zero competence in all things electric...I have been following this thread silently.  This would seem to be good news though and happy you are able to stuff those moths back into the purse :)

Bill

Online sco

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Re: No, No this could be expensive!
« Reply #32 on: November 11, 2013, 01:14:42 PM »
:o

Another man trying to encourage me to spend money on desirable things, it is very difficult but I am trying to be a good girl. :embarassed:

Jo

Would you prefer it if we encouraged you to spend it on lipstick and lingerie instead?  :mischief:
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Offline Jo

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Re: No, No this could be expensive!
« Reply #33 on: November 11, 2013, 01:25:37 PM »
Would you prefer it if we encouraged you to spend it on lipstick and lingerie instead?  :mischief:

It depends if it would be to my advantage  :naughty:

I  can't remember if I have any lipstick but I have plenty of other interesting things that I hope to find an excuse to make more use of :embarassed:

Jo
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Offline gerritv

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Re: No, No this could be expensive!
« Reply #34 on: November 11, 2013, 03:50:27 PM »
Repairing anything always (to me at least) seems so much more rewarding than simply replacing. And sometimes a challenge.

Gerrit
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Offline Jasonb

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Re: No, No this could be expensive!
« Reply #35 on: November 11, 2013, 04:48:50 PM »
Good news by the sound of things.

Now we just need to stop you looking at Homeworkshop to see all that tooling your friend Eric is selling :ShakeHead:

Offline Jo

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Re: No, No this could be expensive!
« Reply #36 on: November 11, 2013, 05:16:45 PM »
Its not that sweetie Eric or my friends Chris and Steve who have the tempting items, its Digger and Tim who have both of  them  ;D

But I am trying to be good girl but as you know I find being good so difficult :embarassed:

Jo
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Offline Jo

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Re: No, No this could be expensive!
« Reply #37 on: November 15, 2013, 03:40:44 PM »
Finally the contactor has arrived. A bit of panick set in when I compared it to the other one as it only has 8 contacts on the top where as the original has 10, it is right as the other two are on the side.



Peter was right it won't fit where the original was time to do some mods  :(

Jo
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Offline Jo

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Re: No, No this could be expensive!
« Reply #38 on: November 15, 2013, 03:45:20 PM »
if anyone else needs these the box it came from was labeled

Type: B10VR/M
Voltage 230VAC
Monitor Range: 500VAC/700VDC.

from "Broyce Control ": www.broycecontrol.com Tel 01920 773746

Jo
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Offline Stuart

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Re: No, No this could be expensive!
« Reply #39 on: November 16, 2013, 08:26:39 AM »
Jo are you Ok not had a update hope its not a  :zap:

Stuart
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Offline Jo

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Re: No, No this could be expensive!
« Reply #40 on: November 16, 2013, 09:18:15 AM »
Sorry for the delay a man brought me a bit of wood to play with, so then I had to lite it up for him after that I was too tired to want to risk playing with electrics :embarassed:

I removed the old mounting plate with a cold chisel and drill two new holes to allow it to mount slightly higher. Then moved each wire from one contactor to the other to make sure I got the wiring right.



So it is now in place:



Its a bit tight, I tried mounting it higher but then the wires fouled the cabinet.

Turned it on, it starts the Harrison Mill a treat with no nasty noises  :whoohoo:. The colchester is refusing to start even with a pilot motor but I think that is a temperature problem so I am going to heat the workshop a bit and try her again.

Jo

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Offline Stuart

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Re: No, No this could be expensive!
« Reply #41 on: November 16, 2013, 09:33:08 AM »
Good work

if it starts the mill OK i would say its a good un

can you not slip off the belts on the lathe or have you persuaded it back into its home

forgot to put my heating on in the WS evan the myford with the belts off had a fair bit of drag on the spindle


Stuart
My aim is for a accurate part with a good finish

Offline Jo

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Re: No, No this could be expensive!
« Reply #42 on: November 16, 2013, 09:33:54 AM »
I have just started the Colchester out of gear... lots of smoke... Time to swap for that spare motor...  :wallbang:

Jo
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Offline Stuart

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Re: No, No this could be expensive!
« Reply #43 on: November 16, 2013, 10:10:06 AM »
Ouch  :zap:

thats not good you have let out the magic smoke  :cussing:  hope the spare is full of the said smoke so it should be OK

I know you will but best to hook it up outside of the lathe

bet a pound to a shilling thats the root cause of the converter failure , have you tried it on the mill to prove its OK


Stuart
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Offline Jo

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Re: No, No this could be expensive!
« Reply #44 on: November 16, 2013, 10:24:10 AM »
The Harrison mill is running a treat  :ThumbsUp:

(The new contactor is bigger and louder than the old one)

Jo
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Offline steamer

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Re: No, No this could be expensive!
« Reply #45 on: November 16, 2013, 11:18:48 AM »
I remember the day I started old Norm up in top gear in a cool shop...and he tried...and then the magic smoke came out of the motor...and the electrical box...all at the same time....seems I blew and shorted the motor caps which fried the box....I ended up rewiring the machine AND putting in a new motor!....sounds like you got off easy Jo.

Dave
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Offline Don1966

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Re: No, No this could be expensive!
« Reply #46 on: November 16, 2013, 02:25:25 PM »
Jo, sorry to hear about the smoke and glad you have the convertor fixed. But I hate to sound like a broken record. Make sure to amp check any motor you install right when you turn it on. Failing to do this can result in a burnt motor.

Regards Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #47 on: November 16, 2013, 02:43:58 PM »
New motor wired up. I have spun her up off the machine and no nasty smells  ::)



Spinning over she is taking  :o very little current, so next job mounting the motor in the lathe I am hoping that the existing holes will line up  ;).

Jo
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Offline Jo

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Re: No, No this could be expensive!
« Reply #48 on: November 16, 2013, 03:29:54 PM »
 :pinkelephant: :pinkelephant: :pinkelephant:

I also took off the cover on the old motor.. spot the burnt out winding  ::)
 


Time to put the workshop back together. I still have not worked out why the 3HP Colchester takes less current than the 2HP Harrison under no load  :headscratch:.

Jo
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Offline Don1966

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Re: No, No this could be expensive!
« Reply #49 on: November 16, 2013, 03:45:14 PM »
Looks like you loss a leg and single phased. Amp check all legs and this would not of happen. Bummer to have a burnt motor.

Don

Offline AOG

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Re: No, No this could be expensive!
« Reply #50 on: November 16, 2013, 04:26:44 PM »


Time to put the workshop back together. I still have not worked out why the 3HP Colchester takes less current than the 2HP Harrison under no load  :headscratch:.

Jo

A motor like that draws the most current when starting. As the motor speeds up it generates back EMF that reduces the apparent current required to run the motor. When the forces hit balance the motor stops accelerating and runs at a steady speed. When you put it under load you will see the current increase.

Tony

Offline Jo

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Re: No, No this could be expensive!
« Reply #51 on: November 16, 2013, 04:39:04 PM »
Thanks Tony  :ThumbsUp:

I was more intregued that the larger motor was in no load condition taking less amps. I also noted that the new 3HP Colchester motor needs a lower boost setting on the 3 phase converter than the old one used to :headscratch:.

Jo
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Offline Admiral_dk

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Re: No, No this could be expensive!
« Reply #52 on: November 16, 2013, 06:59:38 PM »
Hi Jo - with you technical background I'm sure that you know this (but have forgot), so since your asking.

I repair quite a number of guitar / PA Amps over time (and still do some) + have wound my own transformers and I have seen the text book confirmed quite a number of times, so I'm sure this applies to electric engines as well.

When applying power to a newly repaired Amp (or a checking a bad one), technicians normally use a Variac (variable transformer) to start at zero Volts and then slowly increase the voltage while checking the current consumption - this is a very good way to avoid catastrophes if you overlooked a serious fault. Doing the same to just an unloaded transformer and plotting the resulting current, you'll discover that a few volts over the designed max voltage, you'll get a sharp rise in the idle current - from almost nothing to destruction in a small distance.

I've also learned that you sometime design a new transformer, only to discover that you can't quite fit all the copperwindings in the bobbin and that the next size up can't fit the overall design .... what to do ?.... You decrease the number of turns on all the windings by IE.: 1-5% and try again. In most cases it works OK, but you will increase the idle current and loss in your transformer - I'm as stated sure that this applies to engines as well.

Offline Jo

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Re: No, No this could be expensive!
« Reply #53 on: November 16, 2013, 07:17:31 PM »
(A_dk sadly your country is one I have yet to visit  :-\...One day (on company expenses  :naughty:))

I don't have a variac.... But maybe you are right the replacement motor is younger than the original and hence it is requiring less starting/no load current.

I think I will start looking for a new 2HP motor for the Harrison and in the meantime I must learn not to say no to any opportunities that present themselves :mischief:

I hope that this thread will be of use to others should they have the miss fortune of their own three phase converters contactors fail so that they many manage to avoid burning out their electric motor in the way this has, which could have been so so much more expensive :'( than the fault itself if I had not already had a replacement

Total repair cost = £27.  It could have been cheaper if the contactor had been brought from that far eastern country ...

Jo
Usus est optimum magister

Offline Don1966

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Re: No, No this could be expensive!
« Reply #54 on: November 17, 2013, 12:50:37 AM »
Thanks Tony  :ThumbsUp:

I was more intregued that the larger motor was in no load condition taking less amps. I also noted that the new 3HP Colchester motor needs a lower boost setting on the 3 phase converter than the old one used to :headscratch:.

Jo
Jo, does your name tag on the motor have a dual voltage rating? Your motor connect is a Y connection. For a six lead motor and dual voltage rating it should be Delta. I have also seen motors have what's called Y start, Delta run on very small motors. Which is not really required for fractional HP. This could explain the low run current at no load, in which case loss of HP.



Time to put the workshop back together. I still have not worked out why the 3HP Colchester takes less current than the 2HP Harrison under no load  :headscratch:.

Jo

A motor like that draws the most current when starting. As the motor speeds up it generates back EMF that reduces the apparent current required to run the motor. When the forces hit balance the motor stops accelerating and runs at a steady speed. When you put it under load you will see the current increase.

Tony
Sorry Tony no disrespect here but that best describes a DC motor not AC. An AC motor in simple terms works like a transformer. You have the primary, " the stator" , the secondary winding, "  the rotor. The difference being that the secondary winding on the motor is shorted. The rotation is caused by the induced currents opposing the current that produced them. Referred to as Lenz law.  So the rotor is trying to catch up with the rotating magnetic field but will never reach synchronous speed it will always be behind because of slip. When the rotor is locked it is just like taking the secondary of a transformer and shorting the secondary together it will pull a lot of current. This short is reflected back into the primary and will burn it.
When the motor is in a still position we have to over come the forces to get it turning and it will draw three to four times it's normal current to do this and reach full speed which is almost the speed of the rotating magnetic field. Slowing the speed of the motor with loads, the motor has to pull more current to produce more torque to return to it's fixed speed.

Regards Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #55 on: November 17, 2013, 07:44:05 AM »
Don, She is a dual voltage rating so she could be wired in star or delta. I have left it as star as that was the way the original motor was wired and how the Colchester Manual shows.

I am very pleased that I have got everything up and running again   :cartwheel: I just hate to think what that new Colchester motor would have cost  :o if I had not already had a spare (maybe I will give my ex one brownie point for acquiring it  :LittleDevil:) .

Jo
Usus est optimum magister

Offline Stuart

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Re: No, No this could be expensive!
« Reply #56 on: November 17, 2013, 08:31:24 AM »
Jo

as I was for a year during my apprenticeship ( at the local iron works so it was heavy power not house bashing ) I did armature and stator winding

as to the off load running amps a lot of factors come into play
no. poles
star/ delta connection  to get the correct supply volts , it depends on how the motor was designed
the copper iron ratio
dose the motor have a fan and the other not
condition of the bearings

in all unless the difference is great do not worry there are to many variables

glad you have it sorted from my experience (limited ) with static converters is that they do not produce a output that is exactly balanced in both volts and phase difference

get it back together and enjoy your machines

Stuart



My aim is for a accurate part with a good finish

Offline Don1966

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Re: No, No this could be expensive!
« Reply #57 on: November 17, 2013, 03:27:18 PM »
Don, She is a dual voltage rating so she could be wired in star or delta. I have left it as star as that was the way the original motor was wired and how the Colchester Manual shows.

I am very pleased that I have got everything up and running again   :cartwheel: I just hate to think what that new Colchester motor would have cost  :o if I had not already had a spare (maybe I will give my ex one brownie point for acquiring it  :LittleDevil:) .

Jo

Jo, if your motor is dual voltage and you are running it on 240 volts you need to connect it Delta. Otherwise you are running at half voltage and low HP. This explains the low current draw you had. Under heavy loads it will draw heavy current even at half voltage trying to give you what you need. If you are happy the way it is and doesn't bog down with heavy cuts leave it as is by all means. But I would amp check it with heavy cuts just to see.The name plate should show two current ratings and it's current rating is now the higher voltage current rating which is half with this connection. Anything over this is overload
Jo I am just trying to help here and I do do this for a living.

Regards Don

Offline Jo

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Re: No, No this could be expensive!
« Reply #58 on: November 17, 2013, 03:36:32 PM »
Thanks Don :ThumbsUp:, I am running it on 415V 3 phase. Nothing (even 5mm deep cuts in steel  >:D ) has ever managed to stall the Colchester.

The Harrison current demands seems to have settled down so I am assuming the oil in her gearbox was cold. Both machines are now happily starting on a lower boost setting than before  :whoohoo:

Jo
Usus est optimum magister

Offline Don1966

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Re: No, No this could be expensive!
« Reply #59 on: November 17, 2013, 05:07:35 PM »
Great Jo, I am glad to here that.


Don