Hi Our solar system (2x100w panels with a new1x 120agm battery) was working fine. We did a 9 day free camp last year with helping out with a genie of course and all went well. Then last week we had full sun and it was only going up to 12. Put genie on went up to 13 only then when we turned genie off it dropped immediately to 12.2 but showed .9 going in at night. The next day showed nothing going in when in the full sun but at night showed 1.0 going in?????
Kim
Aus-Kiwi said
02:42 PM May 24, 2016
Full moon or parked under a street light ? I suggest it's zero at night and the gauge is not calibrated ..
gandk said
02:45 PM May 24, 2016
Hi Yes I know it is supposed to be zero and has been up until last week but wondering what may have gone wrong to cause the strange things it is doing.
Woody46 said
05:30 PM May 24, 2016
Hi folks. I have never had much success with the regulator that is supplied with the panels. Might be a thought, easy to bypass them but of course you need a good one in the line. Cheers all. Woody46
Muzzlehatch said
05:54 PM May 24, 2016
@Woody46. You mean running the pannels directly to the bateries with no regulator? When I my regulator blew up I started doing exactly that however making sure I did not over charge the batteries. The main problem I can see is that it is an impeadance mismatch and thus an inefficent power transfer AFAIK. A bit of a dilema when it would cost less to chuck in another 200w panel than to put in an impeadance matching power regualoter.
Vince said
07:04 PM May 24, 2016
First check would be all fuses.
Second check would be wiring.
Third check would be battery, even new ones can faulter.
Fourth check would be the regulator.
Fifth check would be each panel.
A multimeter will be most helpful.
Simply going through a process of check and eliminate to find the source causing the issue.
Woody46 said
08:44 AM May 25, 2016
Maybe I should have said a good regulator in line. Perhaps they have already done that. I don't like the elcheapo regulators that come with panels. Cheers all. Woody46
gandk said
08:56 AM May 25, 2016
Thank you all but especially Vince for the common sense approach as we are not tech savvy. Hubbie had checked all fuses and today will do the rest in order. Found someone hear with a meter. Will let you know how we go.
Cheers
Kim
PeterD said
10:47 PM May 25, 2016
Muzzlehatch wrote:
@Woody46. You mean running the pannels directly to the bateries with no regulator? When I my regulator blew up I started doing exactly that however making sure I did not over charge the batteries. The main problem I can see is that it is an impeadance mismatch and thus an inefficent power transfer AFAIK. A bit of a dilema when it would cost less to chuck in another 200w panel than to put in an impeadance matching power regualoter.
Mark, please explain this impedance mismatch?
Muzzlehatch said
11:05 PM May 25, 2016
AFAIK the MPPT type charge controller is a switchmode regulator - essentially a DC / AC / DC transformer that matches the aparent internal resistance of the PV array to the internal resistance of the battery pack and keeps that tracking despite level of charge on the batteries and amount of current available from the PV array. When the Impeadance of the load equals the impeadance of the power source maximum power transfer can take place. Obviously it also has charge cutout to prevent overcharge as well.
I hope I am not "Nuking It" . I.E. "In theory there is no difference between theory and practice but in practice there is."
PeterD said
11:26 PM May 25, 2016
A solar panel does not have an impedance that you can define so the theory you quoted does not apply. The other thing, who said the OP has an MPPT regulator. If he has a PWM regulator then when it is working flat out it approximates a solar panel connected to the battery through a diode.
Muzzlehatch said
12:38 AM May 26, 2016
Woody talks obliquely about not using a regulator at all. I have seen systems that just use a relay to switch off the panels once the batteries are up to charge.
I was always under the impression that by measuring the OC voltage (0watts) and the CC current (also 0watts) as well as setting up a load line at intermediate loads one could determine the point where the product of voltage and current i.e wattage was at its maximum. This then could be compared with the point at with the battery charge current was at it's optimum. It is likely theat the internal resistance (impeadance since it is non linear ) of load and source will not be the same.
The MPPT regulator dynamicly matches these two voltage / current ratios to each other. I am no expert.
My point is even with a rough as guts mismatch the choice is for the same money to wack up another 250 wattts of PV or increase effieciency with a MPPT regulator.
Woody46 said
06:55 AM May 26, 2016
Hi all. I use a Power Tech MP3722 charge controller. My original point was the supplied controller will let you down. Anyway enough of this, I rather think that I would like to change with Clancy also, Wait on I'm a permanent traveller, I think I've at least joined him. Take It easy folks .Cheers. Woody46 l
Hi Our solar system (2x100w panels with a new1x 120agm battery) was working fine. We did a 9 day free camp last year with helping out with a genie of course and all went well. Then last week we had full sun and it was only going up to 12. Put genie on went up to 13 only then when we turned genie off it dropped immediately to 12.2 but showed .9 going in at night. The next day showed nothing going in when in the full sun but at night showed 1.0 going in?????
Kim
Hi Yes I know it is supposed to be zero and has been up until last week but wondering what may have gone wrong to cause the strange things it is doing.
Hi folks. I have never had much success with the regulator that is supplied with the panels. Might be a thought, easy to bypass them but of course you need a good one in the line. Cheers all. Woody46
@Woody46. You mean running the pannels directly to the bateries with no regulator? When I my regulator blew up I started doing exactly that however making sure I did not over charge the batteries. The main problem I can see is that it is an impeadance mismatch and thus an inefficent power transfer AFAIK. A bit of a dilema when it would cost less to chuck in another 200w panel than to put in an impeadance matching power regualoter.
Maybe I should have said a good regulator in line. Perhaps they have already done that. I don't like the elcheapo regulators that come with panels. Cheers all. Woody46
Thank you all but especially Vince for the common sense approach as we are not tech savvy. Hubbie had checked all fuses and today will do the rest in order. Found someone hear with a meter. Will let you know how we go.
Cheers
Kim
Mark, please explain this impedance mismatch?
AFAIK the MPPT type charge controller is a switchmode regulator - essentially a DC / AC / DC transformer that matches the aparent internal resistance of the PV array to the internal resistance of the battery pack and keeps that tracking despite level of charge on the batteries and amount of current available from the PV array. When the Impeadance of the load equals the impeadance of the power source maximum power transfer can take place. Obviously it also has charge cutout to prevent overcharge as well.
Ref: https://en.wikipedia.org/wiki/Maximum_power_transfer_theorem
I hope I am not "Nuking It" . I.E. "In theory there is no difference between theory and practice but in practice there is."
A solar panel does not have an impedance that you can define so the theory you quoted does not apply. The other thing, who said the OP has an MPPT regulator. If he has a PWM regulator then when it is working flat out it approximates a solar panel connected to the battery through a diode.
Woody talks obliquely about not using a regulator at all. I have seen systems that just use a relay to switch off the panels once the batteries are up to charge.
I was always under the impression that by measuring the OC voltage (0watts) and the CC current (also 0watts) as well as setting up a load line at intermediate loads one could determine the point where the product of voltage and current i.e wattage was at its maximum. This then could be compared with the point at with the battery charge current was at it's optimum. It is likely theat the internal resistance (impeadance since it is non linear ) of load and source will not be the same.
The MPPT regulator dynamicly matches these two voltage / current ratios to each other. I am no expert.
My point is even with a rough as guts mismatch the choice is for the same money to wack up another 250 wattts of PV or increase effieciency with a MPPT regulator.
Hi all. I use a Power Tech MP3722 charge controller. My original point was the supplied controller will let you down. Anyway enough of this, I rather think that I would like to change with Clancy also, Wait on I'm a permanent traveller, I think I've at least joined him. Take It easy folks .Cheers. Woody46 l