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Pc50mill blowing fuse


Ricky G.
 

Hi guys,
Rick here with a problem. I bought an emco pc50 mill that came with the old computer system. The mill was running good when I tested the movements. But today when I went back to run it again the power shutoff. I check the fuse box and it was blown so I  replaced it. But it keeps blowing it, please help. I really like this machine and hope you guys can give me hints to find out what the issue is..


@Travis_S
 

Blowing a fuse indicates an electrical short circuit.  The trick is going to be finding it. I would start by pulling out the plugs (one at a time) for the stepper and spindle motors and checking continuity across each wire in relation to the other wires..My guess here is that you have a short in the wires that move, between the controller and the motors. It wouldnt hurt to pull out each control card and visually inspect for obviously burned/damaged components.

Good luck!


Ricky G.
 

Go it tnx for the advise I will do that, I'm not sure how many 6.3 fuses I'm gonna burn out but is worth the try

On Tuesday, September 17, 2019, 8:01:25 PM PDT, <Emcofan31@...> wrote:


Blowing a fuse indicates an electrical short circuit.  The trick is going to be finding it. I would start by pulling out the plugs (one at a time) for the stepper and spindle motors and checking continuity across each wire in relation to the other wires..My guess here is that you have a short in the wires that move, between the controller and the motors. It wouldnt hurt to pull out each control card and visually inspect for obviously burned/damaged components.

Good luck!


cjlear
 

On 18/09/2019 1:24 pm, Ricky G. via Groups.Io wrote:
Go it tnx for the advise I will do that, I'm not sure how many 6.3 fuses I'm gonna burn out but is worth the try

One. Pull out everything previously mentioned, then plug them back in and test one at a time. When it pops again, that's the faulty component.

Cheers

 Charlie


Ricky G.
 

Ok, so far I unplugged all the boards and pulled them, inspected them but nothing seems burned.
Maybe I can explain better, the blowing fuse is the one on the exterior 6.3 next to power plug and rs232,
It blows when I turn the key.
I found in the interior a set of four fuse cases, like brakers all except 1 is 6.2 the other are 2.5. The 6.2 has a stain very small but can't tell if is burn or not.
Hope is explain better. I ran out of 6.3 fuses to continue my testing.

On Tuesday, September 17, 2019, 9:00:51 PM PDT, cjlear <tools@...> wrote:


On 18/09/2019 1:24 pm, Ricky G. via Groups.Io wrote:
> Go it tnx for the advise I will do that, I'm not sure how many 6.3
> fuses I'm gonna burn out but is worth the try


One. Pull out everything previously mentioned, then plug them back in
and test one at a time. When it pops again, that's the faulty component.

Cheers

 Charlie





arjan.dijk
 

Maybe try a different power outlet. 

I had my Mill 55 last year connected to a power box the was used by builders, I could not handle the startup peak of the machine so the power box fuse switched off, maybe this is also your problem.

Using another wall socket solved the problem.

Op wo 18 sep. 2019 om 06:58 schreef Ricky G. via Groups.Io <lablue79=yahoo.com@groups.io>:

Ok, so far I unplugged all the boards and pulled them, inspected them but nothing seems burned.
Maybe I can explain better, the blowing fuse is the one on the exterior 6.3 next to power plug and rs232,
It blows when I turn the key.
I found in the interior a set of four fuse cases, like brakers all except 1 is 6.2 the other are 2.5. The 6.2 has a stain very small but can't tell if is burn or not.
Hope is explain better. I ran out of 6.3 fuses to continue my testing.
On Tuesday, September 17, 2019, 9:00:51 PM PDT, cjlear <tools@...> wrote:


On 18/09/2019 1:24 pm, Ricky G. via Groups.Io wrote:
> Go it tnx for the advise I will do that, I'm not sure how many 6.3
> fuses I'm gonna burn out but is worth the try


One. Pull out everything previously mentioned, then plug them back in
and test one at a time. When it pops again, that's the faulty component.

Cheers

 Charlie





aushacker
 

Hi Ricky,
nobody seems to have asked this one, are you using fast blow or slow blow fuses?

I know nothing about the PC50. The Emco machine I do have access to, a Compact 8 CNC lathe, contains a fairly hefty linear power supply. This means that the mains goes via the fuse to a large transformer followed by rectifier diodes and some large capacitors. There is a large inrush current when you first turn it on as the capacitors appear as a short circuit.

If your machine has this setup you need to be using a slow blow fuse.

Cheers,
Steve


Ricky G.
 

Hi Steve, I was using the fast acting fuse, so I need a slow blowing one then?
There's other fuses but it only blowing this 6.3L by the exterior box
All other fuses from the box boards are not blown. I see light come up, but shuts off

On Tuesday, September 17, 2019, 11:33:08 PM PDT, aushacker via Groups.Io <sjdavies2@...> wrote:


Hi Ricky,
nobody seems to have asked this one, are you using fast blow or slow blow fuses?

I know nothing about the PC50. The Emco machine I do have access to, a Compact 8 CNC lathe, contains a fairly hefty linear power supply. This means that the mains goes via the fuse to a large transformer followed by rectifier diodes and some large capacitors. There is a large inrush current when you first turn it on as the capacitors appear as a short circuit.

If your machine has this setup you need to be using a slow blow fuse.

Cheers,
Steve


Manfred Vormbaum
 

For what it's worth, and in an effort to save some fuses, you may want to check some of the stepper motors for shorts to ground. When you have the connectors to the motors disconnected, check each phase to ground and also check the resistance across the coils. The latter would likely require a multimeter that can measure less than 200 to 500 Ohm full scale since the DC resistance may be quite low.

Manfred

On Wed, Sep 18, 2019, 11:30 AM Ricky G. via Groups.Io, <lablue79=yahoo.com@groups.io> wrote:
Hi Steve, I was using the fast acting fuse, so I need a slow blowing one then?
There's other fuses but it only blowing this 6.3L by the exterior box
All other fuses from the box boards are not blown. I see light come up, but shuts off
On Tuesday, September 17, 2019, 11:33:08 PM PDT, aushacker via Groups.Io <sjdavies2=icloud.com@groups.io> wrote:


Hi Ricky,
nobody seems to have asked this one, are you using fast blow or slow blow fuses?

I know nothing about the PC50. The Emco machine I do have access to, a Compact 8 CNC lathe, contains a fairly hefty linear power supply. This means that the mains goes via the fuse to a large transformer followed by rectifier diodes and some large capacitors. There is a large inrush current when you first turn it on as the capacitors appear as a short circuit.

If your machine has this setup you need to be using a slow blow fuse.

Cheers,
Steve


aushacker
 

Hi Ricky,
probably slow blow but are you able to post some pics of the inside of the control box to confirm? I've seen a few photos but want to be sure. From what I understand the cabinet is divided in two with the power supply in the left half and the control electronics on the right. The power transformer is probably top centre, just to the left of the divide.

If anyone out there has soft copy documentation for the PC mill 50 are you able to upload to the files section?

Cheers,
Steve


Ricky G.
 


Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.
,

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.
,

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.
,

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.
,

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.
,

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

Hi Steve, yes, I was able to bypass without blowing the fuse now. Before I disconnected everything and plugged the power and it was still blowing the fuse. Next I decided to check on the rectifier, the one that has 4 legs and try powering it without connecting the boards. I had a spare power unit with same rectifier so I switched them. Sure then the power continue without burning the fuse. So The problem was the rectifier. I still yet haven't connected the boards since I wanna make sure to purchase the 6.3 fuse and test everything again.

On Wednesday, September 18, 2019, 9:32:15 PM PDT, aushacker via Groups.Io <sjdavies2@...> wrote:


Hi Ricky,
probably slow blow but are you able to post some pics of the inside of the control box to confirm? I've seen a few photos but want to be sure. From what I understand the cabinet is divided in two with the power supply in the left half and the control electronics on the right. The power transformer is probably top centre, just to the left of the divide.

If anyone out there has soft copy documentation for the PC mill 50 are you able to upload to the files section?

Cheers,
Steve


calmissile@...
 

Ricky,

Glad to hear your making progress.   A couple of comments.................. We don't know why the rectifier shorted out.  It sounds like you replaced the power supply unit rather than just the rectifier component.  If so, the cause of the original failure could be anything downstream of the rectifier component (bridge, etc).   You indicated that you ran the test with all the boards unplugged.  Electrolytic capacitors are perhaps the most common failures in all electronic equipment.  If the failed power supply has one, then it's possible that it caused the shorted rectifier.

One last note.   If one of the boards has a short, it could also be what took out the original power supply.   I would recommend to start with a Fast Blow fuse of the same value and plug your boards in one at a time to make sure that the short is not on one of them.  By using a Fast Blow fuse you are less likely to fry the new power supply.  If all goes well, you can then replace the fuse with the original specs. 


Ricky G.
 

What, I did was just replaced the rectifier from the new power unit, I became curious to do this cuz before I ran with this problem on a different control unit, that unit had a reset button that instead of blowing fuses it just pop the reset. By looking inside the unit notice the rectifier had bubbled on th black plastic, bought a new one and that made the power to continue. On my pc50 I saw the similar rectifier and decided to try that and that's how I find out the fuse is not blowing anymore. To verify that that was the issue I reinstalled the old rectifier and again fuse blow again. Is very strange but it work, the fan go on and I'm happy. Tnx for the you guy's advise, I became a little scared.

On Thursday, September 19, 2019, 2:01:25 PM PDT, <calmissile@...> wrote:


Ricky,

Glad to hear your making progress.   A couple of comments.................. We don't know why the rectifier shorted out.  It sounds like you replaced the power supply unit rather than just the rectifier component.  If so, the cause of the original failure could be anything downstream of the rectifier component (bridge, etc).   You indicated that you ran the test with all the boards unplugged.  Electrolytic capacitors are perhaps the most common failures in all electronic equipment.  If the failed power supply has one, then it's possible that it caused the shorted rectifier.

One last note.   If one of the boards has a short, it could also be what took out the original power supply.   I would recommend to start with a Fast Blow fuse of the same value and plug your boards in one at a time to make sure that the short is not on one of them.  By using a Fast Blow fuse you are less likely to fry the new power supply.  If all goes well, you can then replace the fuse with the original specs.