Gti is adding, not subtracting current

[brokenspanner]

my grid tie inverter works fine at a friends house, when I install it at my home its working opposite to what it should??? My clamp meter shows 0.12mA when most items are turned off, when I connect my gti it jumps to 70mA!

I would appreciate any ideas... I do have a v phase connected to the distribution board, but cant understand why that would interfere....

 

[OzSolar]

Hmnnn... I'm not following you. Welcome to the forum by the way!

A few things:

-Are you using a clamp meter that is capable of reading mA? A standard clamp meter cannot be trusted to do that.

-Amps without volts aren't that meaningful.

 

[brokenspanner]

Hmnnn... I'm not following you. Welcome to the forum by the way!

A few things:

-Are you using a clamp meter that is capable of reading mA? A standard clamp meter cannot be trusted to do that.

-Amps without volts aren't that meaningful.

When I took a 150w panel and gti to my friends house, we saw the small amount of energy she was using drop to zero when the gti was connected. At my home address, my clamp meter rises when the gti is connected. I have a v phase unit attached. I'm wondering if this is messing up my gti?

 

[OzSolar]

There are far too many variables to be able to make any sort of assumptions about if it's working properly plus I have no idea what a v phase unit is.

 

[RCinFLA]

GFCI use an integrated circuit to detect signal from toroidal current balance bridge transformer and drives a latching relay solenoid.

It draws some small amount of power to run the integrated circuit. The 70 mA looks large because the DC power supply for IC is likely derived from a small series capacitor from AC mains resulting in a very poor power factor load. Actual power is much less than V*A of GFCI power supply.

 

[OzSolar]

GTI, Grid tie inverter is what I think the OP is talking about.

 

[RCinFLA]

I am guessing he is using one of illegal and somewhat dangerous small Chinese plug-in grid tie PV inverters with a small PV panel.

The inverter draws some current from AC when plugged in, so current to or from grid plug depends if PV is producing more power than the GT inverter draws.

Hopefully he doesn't back feed enough to trip a smart meter alert to utility company.

 

[OzSolar]

I am guessing he is using one of illegal and somewhat dangerous small Chinese plug-in grid tie PV inverters with a small PV panel.

The inverter draws some current from AC when plugged in, so current to or from grid plug depends if PV is producing more power than the GT inverter draws.

Hopefully he doesn't back feed enough to trip a smart meter alert to utility company.

That's totally what he's (she/them) is doing and hopefully it DOES tell on itself. Play stupid games win stupid prizes.

 

[JoeHam]

Could your CT or current meter be installed backwards ?

 

[brokenspanner]

GTI, Grid tie inverter is what I think the OP is talking about.

Yes!

 

[brokenspanner]

Could your CT or current meter be installed backwards ?

Its a straight forward clamp meter....

 

[brokenspanner]

That's totally what he's (she/them) is doing and hopefully it DOES tell on itself. Play stupid games win stupid prizes.

My electrical supplier charges me 44p per kwh, I have an economy 7 meter but no storage heaters. Energy companies seem to be able to charge whatever rate they like with economy 7 meters. I have limited capability for work and simply trying to reduce my bills. Positive feedback is much more helpful than sarky remarks....

 

[RCinFLA]

Positive feedback is much more helpful than sarky remarks....

If you have young children, the best advice is throw thoughts inverters in the trash.

When plug is pulled from AC outlet when there is PV incoming power, the exposed male AC plug prongs may have live mains voltage level AC for some period of time after unplugging them.

 

[OzSolar]

Positive feedback is much more helpful than sarky remarks....

I think you mean snarky*... Sorry, I couldn't help myself.

But back to helpful. Please read my first reply again. Note that I mentioned that you cannot use a regular clamp meter to measure mA. It is not even close to accurate down that low. What you're doing isn't telling you anything that can be used to make troubleshooting decisions. Google mA clamp meter and see what it returns.

Also in the name of being helpful I trust you have taken all the other possible measures to reduce your energy consumption. Efficiency is cheaper than solar in most cases.

*LOL I just learned something. We in the US use "snarky" and the British use "sarky" which makes more sense. Short for sarcastic.

 

[RCinFLA]

If PV input power is less than inverter electronics overhead consumption to run the inverter there may be some AC input current flow into inverter.

Inverter overhead consumption may be anywhere in the range of 5 to 20 watts depending on wattage size of inverter.

There is likely an AC disconnect relay on AC output path but if there is some amount of PV input voltage and inverter is active, the relay will be closed. The sinewave PWM AC filter includes a series inductor and shunt capacitor. The shunt capacitor will have reactive (capacitive) AC current flow whether there is positive or negative power flow from AC port if connect relay is engaged.