[Muggins]

Hello again,

I was hoping not to have any problems for a bit , but what can you do. Couple weeks back Mike Kilroy :wave: helped me pin point my issue with my power supply and I found one that has been working fine for a few weeks till now. Today I was running fine , Mill running fine with air comp coming off and on, programming any rpm and going straight to it no issues ( 4500 rpm with no ramp up unlike my old psr.). My lathe guy comes in and starts the lathe and my mill alarmed with drive signal has been lost. So currently, I can run my mill at any rpm and have air comp running, but if I start the lathe it kicks me off. My question is, What can be the cause this time? Is it my PSR4/5 acting up again?

Thanks for the help

Dan

Arrow 1000
A2100
1998

[slowlearner]

Dan,
Are you running a phase converter?

[Muggins]

Hey Scott,

No, I m not. I have 208v 3 phase utility power. It measures at between 210-214 at the main incoming contacts of the mill and doesnt dip below that even with the inrush from the air comp starting up. I was running everything in my shop for at least a week without a problem after I changed out the old psr before todays issue.

Thanks

[mike_Kilroy]

Hey Scott,

No, I m not. I have 208v 3 phase utility power. It measures at between 210-214 at the main incoming contacts of the mill and doesnt dip below that even with the inrush from the air comp starting up. I was running everything in my shop for at least a week without a problem after I changed out the old psr before todays issue.

Thanks

I thought I recall you using an RPC...

You emailed: Couple of weeks back you helped me find my power supply issue. I have been running the new(used) one for 2 weeks without issue with my other equipment on simultaniously. Then yesterday I got my axis drive signal lost alarm back when I would start my lathe up while mill was running. The Mill would not alarm when my air comp fired up though. This morning, I start up the mill and now it alarmed with the air comp starting as well, so I am down again. Is this just another bad power supply or could it be something else causing them to go bad? I assume the dc bus is the issue from your info about how these work. I have a warranty on this one and he has a 250-7500 on hand. This one will not work for me right? I need 75amps per phase as on my 275-7500. I dont understand how it worked great for 2 weeks and now gradually does not work. Is there something I can clean or inspect to correct the problem?

First off, the 50amp will be too small.

Sure sounds like you have some AC power spike issue there.... might there be a loose phase wire supplying this mill? is it the same mill that got a failed ps previously? YOu replaced it and the replacement one failed in 2 weeks?

sure sounds like either an issue with your power or you are just unlucky this last month. Could be either. I would:

1) Not buy any lottery tickets for a while
2) triple check all power connections between your wall and the PSR4/5 inside the mill.

I am almost scared to repair one of your PSR/45-275's since it seems it may fail again in short order due to some power source issue you have?

[Muggins]

I will go back though and triple check the connections and post. One thing to note , the psr 4/5 I purchased to replace my other faulty unit was taken from a mill that was parted out. I really dont know the history of it. The psr that was in my Arrow 1000 when I bought it , was bad already before I wired it in my new building. Is there a problem with that voltage input? It remains stable when my other stuff starts up... Is that voltage too close to the min amount need for the psr?


Thanks

[mike_Kilroy]

Is there a problem with that voltage input? It remains stable when my other stuff starts up... Is that voltage too close to the min amount need for the psr?

NO.

[Muggins]

OK. I checked all wiring from panel to machine ...all tight and has continuous. Checked the voltage for any spike/drop again when I start my other equipment and it remains constant. Checked for continuity from dc bus contacts at the psr4 to the other drives( x, y ,z, spindle) ; good. Also checked continuity from regen resistor contacts. One wire goes the southern contact of what looks like a relay(continuity good) and the other wire(from psr regen contact) goes north all the way into the upper enclosure. The northern wire of the relay then goes up into the upper enclosure as well.

Any ideas of what else I can troubleshoot ?


Thanks

[Muggins]

I am reaching here but, I measure almost 1 volt at the machine with power turned off at the panel That is measured across each leg separately, meaning each leg has 1 volt. I do not have a separate ground rod for the machine, it is grounded, just not to its own rod as I have seen used before.
Could that cause my power supply woes?

[meckardt55]

You need to put in a separate ground rod for this machine. It needs to be a 5\8' steel rod copper coated and 8 to 10 feet long, no exceptions. I would say you have a incoming voltage problem, should be 230 VAC for this machine not 208 VAC. You need a step up transformer to get it to 230VAC. You also need to look at the size of all the incoming AC wires that you are using. GO to home depot and buy a smaller compressor to run just this machine and see if you have the same problem. You need to look at the inrush current on your compressor. You should rent a power monitor to check your AC voltage out when you start up.

MIKE CNC Machine Services INC | Cincinnati Milacron MachinesCNC Machine Services

[Muggins]

ok, I will add ground rod. Mike Kilroy was saying that the 210VAC measured input is inside my psr window. I have checked inrush to my other equipment and there is plenty of inrush but the supply to the mill shows no change during other equipment starting up. It was running with no issues for 2 weeks, all equipment running same time. But am I close to the 9.76% the manual shows for allowed voltage difference from 230VAC. 9.76% of 230 is 22.448 , that puts its min supply voltage at 207.5. I am at 210vac

Does anyone know where I can find a step transformer from 208v to 230v 3 phase? I have tried to find one for some time just to take this voltage issue off the table as the cause

[Muggins]

Slowlearner your PM box is full. I tried to reply

Thanks