[OP]
Member
Anyone running a phase perfect ever changed out the caps? I just read in maintenance that they should be changed out every two years. I've never changed mine out. Mine trips occasionally when starting my shaper with large cutters installed. Shaper is a SCMi T-130. It's a hard starting SOB. It's happening more frequently, which made me dig the manual out.
Contributor
i'm very interested in people's experiences with this question. i've done *nothing* with my PP for years. it never trips, i never have an issue, ... but i'm terrified by a multi-day outage. ancillary question, would you buy the replacement caps from PP, or would you buy others?
Originally Posted by joe milana
[OP]
Member
Like I said, the shaper is the only tool that trips it, only occasionally, and it developed a motor problem today, so that may be the problem. Everything else in the shop starts and runs just fine. No idea where I'd source the caps. I'd probably ask the electrical guru's if there is a difference in quality between brands. I wouldn't have a problem paying the PP people a bit of a premium for new caps. They were extremely helpful when I bought the unit, and it's been a great addition to the shop.
Contributor
If the manufacturers manual says to change the caps out every 2 years than I wouldn't even question doing so. Just change them out and if nothing else this will help the performance. I'm not 100% how the phase perfect phase converters work but capacitors in other phase converters are the critical component keeping the power reasonably balanced or at least keeping the current in phase with voltage therefore giving a reasonable power factor. But i would be guessing if I theorized why they exist in your phase perfect device but I can say they are most likely very significant in its operation if the manufacturer is recommending changing them every 2 years.
Contributor
Here is an explanation of why the capacitors should be changed on the phase perfect.Replacement of the capacitors every three years is recommended. These capacitors suppress electrical noise caused by the switching of the IGBTs. If they are degraded the electrical noise can damage equipment connected to the converter.
[OP]
Member
Sage advice. I always figured a Cap either worked, or it didn't. Ill call the PP people tomorrow.
Member
I bought a used (but unused) PP that had sat around for years. It's thought that one of the line caps went bad right away when I started using it. Caps are cheap.....computer boards not so much!
Phase Perfect never really did/could explain exactly what happened but the repair involved pulling the unit out of service, crating it, then shipping to Phase Perfect for repair.
I labeled the caps with the date installed and will most certainly replace them every two years!
If I bought another one used I wouldn't even power it up before replacing the line caps.
Contributor
I would not replace the caps until I notice a problem. It should have a load and line reactor on the pp to protect things up and down stream. Problem with replacing all the caps is the tolerance of the new caps may be far enough out that things will have to be rebalanced. What voltage are the caps and what tolerance?
Bill D
Member
Bill,
It's only the two line caps that they recommend replacing every two years. They're on the two main lines into the unit. Jeff
Contributor
i spent 45 minutes on the phone this afternoon with Darwin at PP. very helpful and informative call, and i have a set of caps coming my way. effectively what he said is that they are impacted by time, and especially by CNC motor braking feedback, and do break down. they should be replaced every year or two, and in some cases, more often. he asked me about the equipment in my shop, and zoned in on those machines with inductive braking. in my case, my PP was made in 2015, and has never had any form of maintenance - he said that if the caps go, what happens is the fuses and boards can go. rather, if you keep up with the caps, they almost certainly protect the rest of the unit. ~$190 for 8 caps, and in my mind that's a no brainer, i'll do it annually.
he provided guidance on how to physically do the replacement, and i'm expecting about an hour of labor. also, he said it's really important to check the fans on the top of the units, as that's another failure point - he says they see cases where one fan fails, and the other fan sucks air through the second fan, rather than through the unit, causing overheating. simple test - put a piece of paper over the fans and ensure they are both blowing, rather than one of them rotating from having air sucked through it by the other one.
i'll report back after i swap the caps if there's anything notable in the maintenance.
(edit - i have the PT3110 model, ~110 amp 3ph output)
--- dz
Last edited by David Zaret; 08-24-2020 at 9:25 PM.
[OP]
Member
Called Phase technologies this morning. Same experience. Good info. New caps on the way. Cheap insurance. Bad caps can cause $2,000 repair bill.
Contributor
joe - this morning i checked my units, and one of my fans was dead. darwin said it's common. check yours. they added a set of fans to my order which hadn't shipped yet.
-- dz
Contributor
I thought it was just a capacitance check with a meter and if within specs you are good to go, you guys are saying that PP says replace them every 2ish years regardless?
mark
[OP]
Member
Thats what they say. I was told that that things like braking feeedback from CNC machines is hard on them, but I dont have any CNC equipment or machines with electronic braking function. They also said that time is hard on these, and at about the 9 year mark, they see failures begin to show up. If they fail, they destroy one of the control boards & that is a $2000 fix. His explanation didn't really make sense.
[OP]
Member
Thanks, I did the paper test and both fans were blowing. I will check them frequently.
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