Dueling Schneiders

[flpilgrim]

Greetings.

Finally got our second inverter hooked up and powering our whole home. Thanks again to the folks on here who helped along the way. Reconfigured my grid support settings so grid backup is automatic and we can not have to fiddle with switches on cloudy weeks.

Has anyone been able to get the last 100w of grid power to stop being drawn while connected? I have my sell at 0 and my shave amps at .1 but I still have a constant draw of 100w from the grid.

Thanks!

 

[flpilgrim]

Could this be reactive wattage that doesn't get billed? Our usage yesterday didn't reflect the 2.4 kw my inverters say they're pulling in.

 

[pvdude]

My XW-Pros do the same thing.
They draw a little from the grid, and leak a little to the grid.

I don't sell back, all that is disabled in the config.
Still draws a little from the grid, even when the PV is fully supporting the loads.

The grid is used only for support, when the PV can't supply the load.
All the loads on the inverters are 240volt.
(I converted all the 120v loads to 240v, using a transformer:

Liebert® TDU | Transformer Distribution Unit

The Liebert® (TDU) Transformer Distribution Unit is a transformer in a rack-tower enclosure with integral distribution and forced air cooling.

www.vertiv.com

This helped a little with the energy leaking back at the grid.

I have not found any way to completely stop a tiny amount of energy "leaking" back to the grid.
On my system, sell is disabled, "Sell amps" is set to zero.
Grid support is enabled.

 

[BentleyJ]

Our XW+ will pull about 100W from the grid with Peak Load Shave Amps set to 0. If the air conditioner or other large load starts up, grid draw will also go up a little. That seems to be normal behavior.
The inverter is reacting trying to keep voltage and frequency synchronized but it cannot so in a single AC cycle.

 

[OzSolar]

I don't sell back, all that is disabled in the config.
Still draws a little from the grid, even when the PV is fully supporting the loads.

How do you interpret your grid watts? I know just enough about power factor be dangerous but I know that those PF's of less than .2 stand out as bad. I've seen that before both on my own house and some commercial buildings that I do contract energy management for so I know it's not uncommon for some loads to have terrible powers factors when they are idling.

To me, that works out to a VA of ~ 500 watts. That makes me wonder if they should be calling 103 VA, not 103 watts.

To me it would make more sense if your VA was 103 and the watts was ~20 watts.

 

[flpilgrim]

Thanks for the input. Cheers.