Solar Input showing as 109 watts at night.

Solar Input showing as 109 watts at night.
Inverters 'off'

Is there a way to make this nearer '0' ?
I believe its also bumping up my daily figure by the same amount.

Bazzle

icarus75's picture

Hi Bazzle,

How do you monitor your PV production? With a DIN-rail meter of with current clamps?

Cheers,
-Bart.

bazzle's picture

With my newish Flukso V2 and its current clamps.
Solar one around wire from inverter output.

I also have a direct recording from the inverters using proprietry software when it is operating. (ProControl serial link to inverter)
The Flukso always reads higher.

This is Flukso
http://i8.photobucket.com/albums/a19/bazzslk230/Flukso/FluksoJan15th12.jpg

This is ProControl
http://i8.photobucket.com/albums/a19/bazzslk230/Flukso/ProControlJan15th...

At about 14:30 there is about 300w difference.
Blue is solar on Flukso
Red on ProControl

Bazzle

icarus75's picture

A grid-tie inverter should have a near unity power factor. The inverter will also shut down when the
available PV power is less than the total loss of the inverter system. So the measured power output should be zero at night and fairly closely track the real output power.

Are you sure that you're not measuring other loads besides the PV inverter with the clamp?

bazzle's picture

No other loads. Clamp on dedicated cct from solar breaker that comes from inverter.
Its always consistently about 116w at night.
You can see it on my graphs on your site.

Got me miffed :(

Bazzle

ghostgum's picture

Is the current clamp in clear space, or is it pushed up against the side of a circuit breaker with its own magnetic field?

bazzle's picture

Its pretty crowded next to the breaker rail so I tried the solar one about 100mm away on the solar input, same thing.
If I remove off the wires completely it goes to '0'.
Ghosts in the box.

Bazzle

DB_Ackermann's picture

Hello. We have the same effect here with seven solar inverters.
We get a base line of 500(+/-0) watts every night. I can reproduce an incremental staircaise graph when i disconnect one by one. Each step is about 500/7 watt.

Solar inverter wiring is completley separated from any appliance. Disconnecting solarinverters results in a base line of zero watts.

I think it is caused by reactive power compensation to the rest of the direct or distant appliances.

Christoph

bazzle's picture

Thank you Christoph.

at least its sort of normal.

Cheers Bazzle

cackermann's picture

Bazzle,

we think about to use a DIN rail counter and using pulse input. Free clamps can be used to measure other appliances.

Christoph

bazzle's picture

Christoph

Can you provide more info please?
Pix, links?

Bazzle

cackermann's picture

A single phase finder costs about 60 Euros in Germany. The 3phase costs ab. 150 Euros

The 2nd one (latronics) is perfekt!

Cheers
Christoph

bazzle's picture

Hi

Do you just run a pair of wires to the Flukso and enable the input on the lan page?
What setting do you give the counts on the sensor?

Cheers Bazzle

bazzle's picture

Ill answer :)

Yes direct conn.
Constant = 0.5 for me (2000 i/kwh)

Cheers all
Bazzle

bazzle's picture

Dropped to .48 to get same reading as inverter.
'0' watts at night last night :)

Bazzle

icarus75's picture

I guess you can now finally sleep at night. :-)

I'm still puzzled that the current clamp gave such an onerous reading for your PV output.According to the theory, a grid tie inverter is unable to produce reactive power itself. Then again, your inverter will be switched off at night. If the inverter has reactive components (capacitors or inductors) in its output circuitry, then the grid will feed reactive current to the inverter when it's switched off.

Cheers,
Bart.

bazzle's picture

As I see I was not alone with that, others here and on other forums too.
It must be due to other induced mag field or ??

Bazzle