Furman PM PRO Power Conditioner Internals and Repair

Very interesting. Thanks for taking it apart and pointing out the innerworkings.

Thanks for the look inside, wondered what set them apart from being just a regular surge protector.

Thank you. I’m looking to see what’s wrong with my Furman line conditioner/sequencer and I saw your video. So now I’m going to open it up and see what I have.

Thank you so much for this teardown. I have a rack power strip witch i modded to add EMI filters to each outlet but now i see i need a little more complex circuit with varistors.

These Furman are expensive but now we know what they really do ! Thanks

That was a really interessting video!!

Really interesting video ... learning too.

That is the exact same unit I had years ago, I got mine shortly after the 20 amp Pro Series was introduced, I had two over the years and both worked well but it was the first one I got that was surprising as it came with a 15 amp plug on the end of it, that would change by the time I got the second one and the 20 amp plug had to be cut off and a 15 amp plug installed.....power conditioners are good "peace of mind" investments.

DUUUUDE! This is actually pretty amazing. I have an old Fuhrman power conditioner thats been collecting dust for years. It pretty much just powers on in protection mode anymore, which means no power to the outlets. I was in a band years ago and the place we practiced was powered from the house next door through extension cords, and my rack started popping more and more until the unit just wouldn't come out of protection anymore. I asked a guy once and he basically described the MOV's like you did (eventually take too many hits to work anymore, etc). Since then, I've gotten to where I can start fixing some things and was thinking of looking at this unit again after so many years. This video was very enlightening. I will ask, just as a secondary opinion for input, if you think that scenario I gave sounds like its a MOV issue? I look forward to hearing your thought. Thanks for doing this!

For most residential homes, there is only 1 phase that feeds the transformer and then the secondary side is center tapped to create two lines of 120V and a neutral, but it is not called split phase. It is referred to as single phase.

Always wondered the line filtering going on in these units. Might as well do the same thing they did by purchasing a nice filtering unit and cramming it in a surge protector. At least the one I get will have both common and differential noise mitigation.

Very good your video. I bought one exactly like this one and when I plugged it in the protection, ground and ampere consumption lights do not work. I think your video will help me solve this.

Interesting video, thanks! That's pretty low effort but acceptable for the price. These are better than super cheap generic rebranded Chinese units, though that's not saying much. Because of all the space, you could always improve on the filtering if you wanted to. There's enough space to put in a higher inductance common mode choke in series. You could even use this as a base for a more accurate system that would respond instantly to overvoltage etc. The most "interesting" power conditioner I've seen in terms of design is Accuphase's PS-1230. It's about 70% efficient (it just seems like a regular high power audio amp with fewer stages if you look at the PDF..). Maybe its one advantage is lack of fans for the available power, the disadvantage being absurd audiophile price. In the end, some AC > DC > AC > Filter solution (aka on-line UPS units) seem like a better deal if you want guaranteed clean power haha.

Can u comment on power condition aspect of these units? I always thought that was a bit of ‘snake oil’ but don’t know the science. A lot of guitarists use furman rackmounts. I wonder if the power conditioner aspect of this or the more expensive units would help minimize unwanted noise and interference in a high gain guitar amp? I’ve found one video that tested emi on a similarly priced furman and it reduced emi a little but not a lot. Great video. Thanks!

Good day thanks so much for the interesting video. My Furman PL PRO DMC just caught a spike. Do you do repairs on them still?

Hello I watched your video today. Thank you for a great review. I have a question to see if you can help me answer it. Had a power outage in my home today for a split second, when I went into the room to turn my equipment on, I realized that my Furman p.m. pro-was completely dead (no lights). Would you happen to know what might've happened? I will be checking for the circuit breaker button in case it does have one in the back but will get to it when my friend can help me access it (I am disabled and cannot do it myself). I would appreciate any help. thanks in advance

Hi, do you happen to have a schematic for this unit? I have one and the ammeter works but the voltmeter doesn't.

Hey. I purchased an furman ar117 and it provides power to all outlets. The only thing is that it has a gun to it now. Do you know if that is something that Could easily be fixed and where the problem may lie and if this could be potentially dangerous to things that I have plugged in?

Hi Brad! thanks for the info! we've been scratching our heads over at the music studio as to what unit is the right one for cleaning power, and how much is a power regenerator necessary? Do you have any videos on that or could you shine some light on the matter? would a transformer based power conditioner like the Monster 2500 pro line do the trick? thanks A

i want my furman pl-pro dmc e repaired.. "protection ok" won't lit on..do you able to do the service?