Massive Hum on Monarchy M-150 Power Conditioners.

[Loco57]

I have a pair of Monarchy M-150 Power conditioners that have a common problem they both have a massive amount of Hummmmm when plugged in so loud infact you can hear them from 10m away and to the point I just can't use them.

These are massive units 75lb each and configured for 240v to 240v as originally I had an issue with regards to over voltage to the house because of a transformer issue from the power company supplying 256v at the house and this is with over 500m of underground mains from the meter box.

I have been in contact with the supplier and then the manuifacturer (Eaton as it turns out) but with no result, currently I am running these into ( or was ) a pair of Hydra V-Ray conditioners with all connections to the equipment with BDC power cables.

The connected equipment is totally silent but the noise from the conditioners is the issue, i have checked the mounting bolts, fitted silicone matting under the Toroidal transformers checked all that i can think of and still no result. Both the supplier and manufacturer I don't think believed me as to just how loud this hum is, done the burn in thing Hot Cold doesn't seem to matter.

Tried different power points nothing, the units did in fact address the overvoltage issue as the power out is exactly 240v rock steady it's just the noise.

Any suggestions?

[HiroPro]

Buy APC. They make gear used in the IT industry and their technology isn't BS like a lot of that "power conditioning" fraudsters.

www.apcav.com

BTW if you have the kinda money and are willing to buy stuff like that M-150 LOL... and are having grounding issues. Why don't you just pay to get an electrician in there and install an isolated ground for your AV rack?

[garylkoh]

Loud hum in a power transformer is usually caused by DC voltages. Do either of the transformers inside the unit feel hot to the touch? Is the one that is hot (warmer) also the transformer that is humming? One is the input transformer, and the other is the output transformer. May be one of the transformers is faulty, or the DC-output blocking on the power amp that generates the output signal has failed.

[Loco57]

Gary thanks for that input. In this case both transformers in both units get quite warm to the touch and this is through the metal case. They are epoxy filled in the centre and secured with a 10mm bolt down onto the chassis, i will need to pull the unit apart to check if it actually has a DC filtering device as per your wiring diagram.

If I am correct the wiring diagram you have attached is of the AC-Regenerator not the M-150 units that I have these are the much larger devices rated at 2kw each ( I think I can attach a photo of them ) these were originally purchased to address the over voltage issue I had from the Power suppliers reluctance to adjust their supply transformer to the correct voltage.

This has not after 20 years of complaining been fixed 256 volts in at the house in place of 230 volts so you see the problem and the issues it caused. I was obviously not talking to the right person as when setting up our Solar paperwork I mentioned this to the inspector and he said he would investigate true to his word he did and verified that my readings were correct and adjusted the taps on the transformer beck to specification.

Noise existed both before and after the adjustments, it is possible that the units were made with the wrong specification transformers for US voltage/frequency even though I enquired about this when the trouble first appeared. The answer I got back was we don't have the 240/50hz supply to test?

Assuming the voltage is US spec could this be the problem and the cause of the noise in the first instance? Just don't know enough about this equipment or electronics/power systems to know in this instance so maybe I have been duped?

[garylkoh]

Hi Loco, I couldn't find any information on the M-150. I thought that it was the AC Regenerator as otherwise it wouldn't fix your over-voltage problem. That is a possibility that it's because the transformers are not rated for 240V/50Hz, but you'd have to ask the manufacturer. Is there a label on the transformers that states the specs?

[fas42]

Hello, Loco. Perhaps you've already read this, but if not, this has some information that may be relevant: http://sound.westhost.com/articles/50-60hz.htm

Frank

[Loco57]

Gary,
haven't noticed any markings on the transformers that I can note. Frank, thanks for the link interseting reading. I suspect that maybe the transformersa are 60hz specification not 50hz and this could account for the problems and the situation with the running temperature as well? On my original contact with Pulizzi Engineering /EATON Corporation the manufacturer with regards to the problems. I have managed to find a link for the specs on the units if this may help with any further information on the issue thanks.
http://powerquality.eaton.com/ePDU-S...3163.aspx?CX=3

[Roger Dressler]

I suspect that maybe the transformersa are 60hz specification not 50hz and this could account for the problems and the situation with the running temperature as well? On my original contact with Pulizzi Engineering /EATON Corporation the manufacturer with regards to the problems. I have managed to find a link for the specs on the units if this may help with any further information on the issue thanks.
http://powerquality.eaton.com/ePDU-S...3163.aspx?CX=3

That Eaton spec sheet states it includes a muffin fan, yet the pictures show no such fan. Makes me go: hmmmm.

Also, this thing will do nothing for your overvoltage problem unless you spec'd it to be a stepdown device. It's advertised as an isolation transformer by trade, and has no regulatory capability. Anyway, now that your power taps are fixed, you have proper 240 at the mains.

The Eaton spec sheet mentions the input voltage is 208v 50/60 Hz, but as it is custom product that comes in at least 4 versions, maybe they support a range of input voltages. What concerns me is the specs for Monarchy M150 (linked earlier) as stated by that reseller anyway, shows it rated for 120V in/out. Maybe that's just the version sold in their (Canadian) market. (The Monarchy website's only description of the M150 is its price.) Being a 1:1 isolation, it will probably function with 240 in/out. But it's not what it wants to do -- especially with no cooling fan. Of course the same website also states it improves bass response, which is nonsense, so maybe the other "facts" are also in error. Anyway, you might want to double check to make sure it's actually rated for 240v use.

BTW, can you trace the chain of custody? Where did you get these units? I doubt you need them.

[Loco57]

Roger,
thanks for your input, with regards to the actual specification when I ordered the units my requirements were for a 230/240 volt output and I mentioned that I had an over voltage issue with the 256 Volts and I queried this twice before ordering the units. I can attest to the fact that indeed the units did rectify the overvoltage issue with a dead on 240 Volt output from the 256 Volt infeed supply so ??? on that one. These units were to replace a 60amp Timonta unit that I had previously destroyed by a lightining strike and in conjunction with a pair of Shiyata Hydra V-Ray units would be my power supply to the audio system.

Despite everything that I have tried to date the noise issue has not been able to be rectified so I just can't use them, the Hydra's seem to be doing the job at the moment as the system is totally silent in operation but I just can't understand why the isolation transformers are so noisy unless as it seems thay are totally the wrong specification but how come they despite all the other issues provide the correct voltage to my system?

Is it possible these units can/have been configured to perform other functions that give these results, it is my understanding that they also provide additional current under high drawoff applications and by virtue improving Bass response?
Who knows I suspect I will never find out the actual configuration and I am not sufficiently tech savy to understand the actual configuration of what I have so will put it down to an expensive folly! x2.

[Roger Dressler]

Despite everything that I have tried to date the noise issue has not been able to be rectified so I just can't use them

They were noisy on day 1, or has it increased over time? And the noise is the same even with no loads connected at all?

I just can't understand why the isolation transformers are so noisy unless as it seems thay are totally the wrong specification but how come they despite all the other issues provide the correct voltage to my system?

If the transformer is not designed for the correct operating voltage range, it could be saturating the core, which leads to not only a distorted sine wave output but could make it noisier because of harmonics in the windings. Not sure you have the option at your house. Here in US we run 240v as split phase, so we can also have 120v. Your mains might be 240v single phase, so no easy way to try driving the unit with 120v to see if that kills the noise. But maybe you know someone with a Variac or other such stepdown device. It would not need to source full rated power because this test would run with no load connected to the M150. (This test only makes sense to perform if your answer about no-load above noise was yes.)

Is it possible these units can/have been configured to perform other functions that give these results, it is my understanding that they also provide additional current under high drawoff applications and by virtue improving Bass response?

If the core is saturated, the efficiency of the transformer is also reduced. That could manifest as less than a perfect 1:1 input/output ratio, hence the effective reduction in output voltage. This is conjecture, but again easy to test. With no output load, measure the input and output voltages with both 240v and 120v inputs. Do the out/in ratios match? Or are they 0.94 for 240, and 1.0 for 120?

If the noise drops significantly at 120, and the output ratio changes from 0.94 to 1.0, that implies these transformers are designed for 120v operation. If Eaton made the units, they should be able to trace the serial numbers back to the build order specs.