PPP - MultiWave and THD

[Still-One]

Ivan
Why would both units act exactly the same way, it really does not make sense. I will have my electrician come over in a few weeks ti check out all connections in the new box.
Jim

[jdandy]

Jim.......I am still floored by the total harmonic distortion numbers you have on your house power. 6.4% seems very high to me. My THD on the input is 1.6% right this moment, and the highest I have ever seen it was 2.1% during the day.

While your electrician is checking things out, ask him to make sure your neutral and your ground are bonded at the point of first disconnect (required by NEC), which is usually your main house panel if it has the main breaker installed in it. Also, if you have a sub-panel fed from your main panel that provides power for your stereo circuits, ask the electrician to make sure the neutral and ground are NOT bonded in the sub-panel. Have him check to see if all your stereo circuits are on the same phase (either A or B). I have all three of my stereo circuits on A phase. It doesn't matter if they are on A or B phase, just that you want them all on the same phase. Let me know what he discovers.

[Still-One]

Originally Posted by jdandy

Jim.......I am still floored by the total harmonic distortion numbers you have on your house power. 6.4% seems very high to me. My THD on the input is 1.6% right this moment, and the highest I have ever seen it was 2.1% during the day.

While your electrician is checking things out, ask him to make sure your neutral and your ground are bonded at the point of first disconnect (required by NEC), which is usually your main house panel if it has the main breaker installed in it. Also, if you have a sub-panel fed from your main panel that provides power for your stereo circuits, ask the electrician to make sure the neutral and ground are NOT bonded in the sub-panel. Have him check to see if all your stereo circuits are on the same phase (either A or B). I have all three of my stereo circuits on A phase. It doesn't matter if they are on A or B phase, just that you want them all on the same phase. Let me know what he discovers.

Dan
Thanks for the suggestions. When we ran the new lines we also swapped out the old sub panel for a new and added a pretty good Square D whole house surge protector.

Also remember my numbers were much lower until I ran Clean Wave.
Jim

[Ryan Conway]

Originally Posted by Stillone

Ryan
Here is what I just performed.

I took readings just now.
With everything hooked up as normal with MW on:
Uncorrected Lt - 6.3% to 6.4% Corrected 1.1 to 1.2
Uncorrected Rt - 6.5% to 6.6% Corrected 1.2 to 1.3
Turn MW off:
UnCorrected Lt 6.4% Corrected Lt 0.9%
Uncorrected Rt 6.5% Corrected Rt 0.9%

Unplug amps from PPP with MW on
Uncorrected Lt 6.3%-6.4% Corrected Lt 1.1%
Uncorrected Rt 6.5% Corrected Rt 1.2%
Turn MW off:
Uncorrected Lt 6.1%-6.2% Corrected Lt 0.9%
Uncorrected Rt 6.3%-6.4% Corrected Rt 0.9%

There is really no change whether the amps are hooked up or not, so the cabling should not be an issue. In general the THD does fluctuate during the day a bit.

Can you provide me with the serial numbers of your units? I would like to try and find another unit from the same production batch and have our engineers perform some tests...

[Still-One]

Originally Posted by Ryan Conway

Can you provide me with the serial numbers of your units? I would like to try and find another unit from the same production batch and have our engineers perform some tests...

Ryan

These are the serial numbers:
PPP- B0-9C0058
PPP- B0-9C0065

Jim

[Ryan Conway]

I did some testing here with our engineers and there is nothing out of sorts with that production batch. The Multiwave waveform is as designed when analyzed and the "compensation" is working correctly.

A little more on what is going on here. When we do Multiwave we add in some 3rd Harmonics. Then when we analyze the THD we look at teh waveform without those. The end result should be a nearly identical output distortion in both standard Sinewave and Multiwave modes.

Now, that being said there are a number of things which can influence the performance of the Premier. Of those the most influential is the incoming power and the second is the connected equipment. Since you have the same reading with or without the amp I would point the finger at the incoming power.

In the end our engineers and I believe any Power Plant Premier in your system will have the same performance. If the relatively small difference in output distortion concerns you I suggest running the units in Sinewave.

Feel free to give me a call at 866-406-8946 if you would like to discuss this in more detail, as it's often difficult to convey everything in a quick posting.

[Still-One]

Ryan. Thanks for the follow-up. I agree that the relatively small increase in corrected THD when MW is on will impact the sound. I am still not sure if I prefer the sound with MW on or off. I spoke with my electrician last evening and he will be returning in a couple of weeks to put my amps on the same phase in the sub panel. He believes that my higher uncorrected THD and compared to others here is due to the number of dimmers in my house.

[jdandy]

Jim.......Glad to here the electrician is coming. Don't forget to have him double check the neutral bonding in the main panel, and no neutral boding in the sub-panel.

The dimmer theory is interesting. Do you often have a lot of these dimmers active at a given time? I have 13 dimmers in my home, but usually never more than two or three active at any given time. When the power is turned off at the dimmer it should not be generating any hash, or harmonic distortion on the AC line. You can test the dimmer verses THD theory by turning off every dimmer, and testing the input THD on the PPP's. If they are the cause of the increased THD you will see a reduction in that value, which in turn should also reduce the output THD as well.

[Still-One]

Originally Posted by jdandy

Jim.......Glad to here the electrician is coming. Don't forget to have him double check the neutral bonding in the main panel, and no neutral boding in the sub-panel.

The dimmer theory is interesting. Do you often have a lot of these dimmers active at a given time? I have 13 dimmers in my home, but usually never more than two or three active at any given time. When the power is turned off at the dimmer it should not be generating any hash, or harmonic distortion on the AC line. You can test the dimmer verses THD theory by turning off every dimmer, and testing the input THD on the PPP's. If they are the cause of the increased THD you will see a reduction in that value, which in turn should also reduce the output THD as well.

The neutral in bonded at the main panel and not at the sub.
My house has close to 40 dimmers. Very few of them would ever be on at any one time especially when I would be listening to music.

[jdandy]

Jim.......Good news on proper grounding and bonding. One less thing to worry about as this puzzel unfolds.