P20 Doing it’s Job


I recently bought the P20 and wanted to share. This is the worst I’ve seen my power, 3.3THD. Its also the first time I’ve seen THD OUT at 0.1%. THD IN is normally around 2% with the OUT at 0.0%. I’d say it’s doing it job tonight! BTW, this is a 20amp dedicated circuit.


Your commercial power is quite clean if you have seen 2% THD in. Mine runs usually around 3.5%. I have my P-10 running on a dedicated 30 Amp circuit. I see the same THD in from both my Solar System and the Commercial AC.


Sixpack: “…I have my P-10 running on a dedicated 30 Amp circuit. …”

A 120VAC 30-amp circuit? Didn’t know that existed. Pray tell.

I have a 20-amp circuit and powercable ready when I order mine. They currently are supplying my 2400-watt Balanced Power Technology balanced-power power conditioner.


It’s probably more appropriate to specify the gauge of the wire used vs. 20amp or 30amp, etc.

I have (2) 10awg dedicated feeds but with 15amp outlets. 10awg can be used for 30amp but requires a twist lock connector (at least to be legal). 20amp requires one ‘blade’ be turned sideways. Standard 15amp both blades are vertical.

I have numerous 30amp circuits at work that are 120v and 208v. Both use twist locks, L5 and L14 respectively. (I think, don’t quote me on the 30amp connectors, it’s been a few years since I built the facility.)

I have a P10 and 2.3-2.6% is typical in, 0.1-0.2% out. I also have solar back feeding the panel, saw no change in the incoming THD when it was added.


You are in a similar situation as I am having Solar for power. I too do not see any difference between the output of the Fronious inverter and the commercial power feed. I agree with what you said about the 30 amp circuit. Yes the wire gauge to the panel box is 10 gauge. I use Hospital Grade Hubble AC receptacles. People do not get that even with 15 amp receptacles you can easily handle delivering 30 amp through them. You just cannot plug in something that will demand 30 amps when the connection is made. That is when the contact would fail. My P-10 also uses an Apex Audio 10 gauge IEC power cord. I am shocked at how little current my system is demanding even when playing at high levels. I am using less than 10% of the capability of the P-10 and it runs as cool as my amplifier. I have higher THD coming in about 3.5% from both solar and commercial get .2 or .3% out of the P-10. I believe we see the same values of THD because our systems are grid connected. It would be interesting to see the output of the Solar if it was off grid with battery back up.


I believe the inverters (14 micro inverters in my case) are rather noisy in their operation. The dedicated circuits and of course the P10 essentially nullifies any impact. The ‘prepaid’ kWh are golden here in expensive-land, aka San Diego.

My entire system uses 2.5amps and very slightly more if cranked. Class D amps and a rather small space…

Standard 15 amp receptacles can handle 100+amps of current, just not for very long.