Power Plant Premier - THD and protection mode advice please

You can call, email, or fill out a service form. See, here.

service@psaudio.com or, you can always go to our website and there under Resources you’ll find a service form you can fill out.

IT has been a while since my last message.
My problem still stands. I have been using both my PPP’s with the problems described above.

Every night, i hear them clicking and going in and out of protection mode.
This can happen 1,2 or 3 times consecutively and then stop.
When this happens, there is a rise usually from 3% THD input to 6%-7% . Voltage input is constant.

I am thinking of investing on a used deal P10, there are several now for nice prices on fleabay.
My question : is the P10 more “robust” to THD input variance ?Or will it click and make noises going into protection also ? I am not interested in investing on a new P10 to find that the problem persists.


Again, your best best course of action is to contact PS Audio.

Have you called, emailed, or filled out a service form?

Yes i did. I got a response inline with the other here. To quote them :

Thanks for reaching out to us about this and sorry to hear that you are having this trouble.

The PPP is designed to power off in the event of a voltage surge.

These can happen in a split second and may not present in the display.

_ _

That both units powered off at the same time is a good sign that both units are factory spec.

As well, if you are driving the PPP’s beyond 80% of their capability they will be more vulnerable to tripping into protection.

I am not using the PPP’s over 80%. The clicking protection mode issue happens even with NO outlet beeing used whatsoever, so the PPP is only responding to the input AC.

Same situation here. I’m located in Germany. The PPP pops in and out even with no load on it! Input voltage is stable measured by Multimeter. THD shown by PPP is coming up when this happens, mostly late at night. BTW: I’ve a seperate power line from the power distribution in the house to the wall outlet powering my stereo.

I doubt PS Audio, as helpful as they are, can resolve this issue without being at the scene on the spot. One of those cases.

Technically speaking, if you have significant DC in the socket, it causes the transformer to lose its efficiency, rather than magnetizing the transformer core, the DC presence only heats the transformer up without transferring any magnetic field for the secondary windings that devices uses to regenerate the power. Lower output forces higher current draw and can result in this buzz. Low output means the regenerator power stage may be short on current/voltage available resulting in high output THD. The protection that kicks in is probably DC protection. The power bank of the PPP, looking at internals pictures, is very small, which means it has little power backup available to continue the normal operation during short power disruptions, supply inefficiency and demands of your equipment. If you look at later PSA models, they all come with more developed power supplies, with larger power banks. These not only help with device power demands when driven hard or power disruptions, but also reduce output impedance and ripple noise.

That is a reasonably constructed thought but it does not explain why the PPP exhibits clicks and protection mode when NO LOAD is present. I mean NO device is connected to its outputs.
Still in this scenario, there are high THD input and output values on screen, and relay clicks showing protection mode. Even with a lower than average power bank, there is no load !
It can be a high DC input, but i believe i can dismistify that, as i happen to have a DC protection circuit in a power cable, so i can test that. I will try and let you know the results. It can be a while, as this behaviour is not predictable.

I’ve owned a PPP, P3 and now P10. The clicking of the PPP, happened to mine, is a bad sign. It’s broken (think they were relatively unreliable - that’s why they brought back manufacturing to the US…speculation on my part of-course).

Maybe you missed the part where i say that PS Audio themselves say the clicking is normal and shows that the PPP is going to protection mode, due to unstable AC power input.
Of course this can be unvisible in the P10…due to better components that can filter this out. Do not know as i never owned a P10.

Sorry, I didn’t pay that much attention. Still, I’ll bet, based upon my limited experience, that it’s broken. Good luck. Hope you get it working correctly.

If it was a single PPP I would suspect it was broken (happened to my first one–a very early model; replacement has been rock steady for ages). Since it is happening to two PPP’s simultaneously, a problem with the incoming power sounds plausible.

The DC can be caused by asymmetric AC in regards to ground, but also if input sine is clipped. Often only the positive AC half is clipped due to how some appliance power supplies are designed. Both reduce transformer efficiency, messing up the output of the secondary. Transformers do not transfer DC over to secondary, it may only mean a distortion (compared to sine wave) on the secondary winding.

In case of my P3, the unit never goes off. Sockets are off via relays, but the whole circuit is active. Think of power plant as an audio amplifier, which only works with one or few frequencies suitable to power up equipment. By looking at it, there are probably 2 amps working in 180 degree out of phase from each other to make the required voltage output. Car amp bridging springs to mind (to double the power output). These amps are working constantly, are biased a good bit, because these massive heatsinks are always warm. They constantly draw current. Anyway, the protection may be triggered not by the DC presence, but the distortion value. Mind, that overloading power plant results in distortion too. It can be an overload protection caused by sensing massive distortion. The software measuring the distortion may not care or aware about the origin of distortion, but rather the value alone. It does its job correctly protecting itself and equipment downstream.

The reason I mentioned capacitance banks, they are quite little to smooth out supply distortion on power rails of the 2 amps. As an amplifier, there is a negative feedback on these amps, that may cause the amp to go unstable and draw massive amounts of power, even if no load is present.