solar panel volts no amps

Submitted: Friday, May 29, 2009 at 18:47
ThreadID: 69306 Views:9327 Replies:5 FollowUps:9
This Thread has been Archived
Installed an 80 watt panel on the roof of my camper today. It was fairly late when I finished but the sun was still up. My solar controller said my input voltage from the panel was around 14v, but my input amperage was 00.0.

How is this possible to have volts but no amps?



Michael

Back Expand Un-Read 0 Moderator

Reply By: Sand Man (SA) - Friday, May 29, 2009 at 18:55

Friday, May 29, 2009 at 18:55
Did you have a load (eg battery) connected?

If there is no load, there is nothing to "create" current, so it is possible to have voltage present, but no current being drawn.

Bill.

Bill


I'm diagonally parked in a parallel Universe!

Member
My Profile  My Blog  My Position  Send Message

AnswerID: 367457

Follow Up By: mintrax - Friday, May 29, 2009 at 19:21

Friday, May 29, 2009 at 19:21
Panel to controller - controller to battery.

All wired up.

Am I missing something...obviously

Michael
0
FollowupID: 635113

Follow Up By: mintrax - Friday, May 29, 2009 at 19:27

Friday, May 29, 2009 at 19:27
Thanks for your reply Sand Man. Get your drift, but the panel is wired up to the controller then to the battery. Turned lights on in trailer to get some load on the battery.

Michael
0
FollowupID: 635115

Reply By: wazzaaaa - Friday, May 29, 2009 at 19:28

Friday, May 29, 2009 at 19:28
If your battery is full it will not accept any charge especially with the low voltage off the panel
AnswerID: 367460

Reply By: Robin Miller - Friday, May 29, 2009 at 19:59

Friday, May 29, 2009 at 19:59
Have a taillight globe in your kit Michael , and just connect it across the panel by itself.

Even on a dull day the filament of the globe should light up a little , indicating the panel is working.

Robin Miller

Member
My Profile  Send Message

AnswerID: 367472

Reply By: Member - Mike DID - Friday, May 29, 2009 at 21:10

Friday, May 29, 2009 at 21:10
"It was fairly late when I finished but the sun was still up."

- you need strong sunlight on the panel to have enough power to charge a battery.

It may have been just barely generating 14 volts but with no reserve to put any charge into a battery.
AnswerID: 367493

Reply By: techo2oz - Friday, May 29, 2009 at 21:14

Friday, May 29, 2009 at 21:14
Yep it is possible for the reg to show voltage but no current. Though I wouldn't expect as high as 14V. I am using BP panels, and if there is ambient light or light indirectly shining on the panels, the reg will show volts just above the battery voltage but no amps flowing.

To see 14V, seems to indicate that everything is connected correctly, otherwise panel alone would be as high as 21V and if no battery the reg may not even start up.

I would check again in full sunlight.

Cheers

Peter
AnswerID: 367496

Follow Up By: mintrax - Monday, Jun 01, 2009 at 14:19

Monday, Jun 01, 2009 at 14:19
Thanks for all the advice on this matter. Put a lamp across the panel as suggested and it light up just fine.

Ran my pc and lights for an hour or so to run down the battery a little. Connected up the panel, sunny with a tiny bit of haze.Turned the pc and lights off and connected panel to controller. Controller showed around 14v but no amps. After a while I actually got 0.4 amps of charge. As soon as I turned on one of the lights the amperage dropped back to 0.

Is this just about the fact that the battery has too much charge in it still? although I would have thought that if the battery is not fully charged that it would still charge it at a rate of more than .4 of an amp.

No sun today.

Am I being impatient and should not worry about this till battery is much lower?

Going north for 3 weeks in 3 weeks so would like to feel that it is working properly b4 I go. Getting good sunny days in Winter might be an issue here in Vic. for a lot of testing.

Michael
0
FollowupID: 635492

Follow Up By: Maîneÿ . . .- Monday, Jun 01, 2009 at 16:09

Monday, Jun 01, 2009 at 16:09
Michael,
To clarify some of your questions 'click' on the words "my Profile" below here.

Some of the pictures shown there will answer the questions your asking!

This pic shows the AGM's are . . 13.1 volt
the solar system is collecting . . 4.9 amp
AGM's are being DRAINED @ . . 3.1 amp
( obviously fridge is drawing 8 amp )

Image Could Not Be FoundMaîneÿ . . .
0
FollowupID: 635508

Follow Up By: mintrax - Monday, Jun 01, 2009 at 19:11

Monday, Jun 01, 2009 at 19:11
Thanks for all the interesting info Mainey.

The only I don'r understand now is, with all 12v accessories off and all input from the panel going into the battery why would the amperage only be 0.4 of an amp ?

Michael
0
FollowupID: 635552

Follow Up By: Maîneÿ . . .- Monday, Jun 01, 2009 at 21:15

Monday, Jun 01, 2009 at 21:15
Michael,
Look at this picture, from the 'my profile' the ~200 Watt Solar system is actually producing 11.8 Amps, but is only allowing 3.3 Amps into the AGM's.

The Steca Solar *regulator* is doing what it should, reducing the Amps to the AGM's because they are approaching 100% SOC.


Image Could Not Be Found
0
FollowupID: 635585

Follow Up By: Maîneÿ . . .- Monday, Jun 01, 2009 at 21:25

Monday, Jun 01, 2009 at 21:25
Bugga, screwed that up, it shows 11.9 Amps (not the 11.8 Amps I posted)
SOC = State Of Charge

The 13.8 Volts is only the charging Voltage, not the true 'rested' battery Voltage.
Trickle charge is usually @ ~13.6v so has a wee bit to go, then the Amps going into the AGM's will be Zero because the Steca is doing it's job correctly.

Maîneÿ . . .
0
FollowupID: 635588

Follow Up By: mintrax - Monday, Jun 01, 2009 at 21:33

Monday, Jun 01, 2009 at 21:33
Thanks Mainey, Yes I understand the concept it's just that amperage of less than half an amp must mean it's basically fully charged. Yes?

Michael

0
FollowupID: 635591

Follow Up By: Maîneÿ . . .- Monday, Jun 01, 2009 at 22:38

Monday, Jun 01, 2009 at 22:38
in just one simplistic word -> "yes"

When the Voltage is in the vicinity of ~14v and next to no (zero) Amps going into the battery (when the Solar system is registering some Amps) you can be assured it's as close to 'fully charged' as it will ever be, as is shown on some of my pics on "my profile" shows it more clearly when more fully understood.

Maîneÿ . . .
0
FollowupID: 635610

Sponsored Links

Popular Products (14)