In a post about Sep18 I said I changed to MPPT controller, as I stuffed my original PWM controller (silly me)
Well have had 2 MPPT's from Jaycar - Powertach 3731,,, 1st one lasted till Easter 19 and packed it in, wouldn't charge.
New one has just started charging one day and not the next.
HAVE ORDERED NEW REDARC PWM, spoke to techie he was VERY helpfull. Back to a simple pwm close the cupboard and monitor in morning and afternoon,, hands off like did for 11 years with original el cheapo pwm.
Terry T1 you were right, I eat humble pie. My MPPT experiment is over.
T1 Terry said
03:55 PM Nov 1, 2019
Well, I've climbed back off the floor and back on the chair, but still a wobbly on the legs What price for the Redarc unit and how many amps does it handle?
T1 Terry
Baz421 said
04:16 PM Nov 1, 2019
$199 and 30a for 480w of panel and 480ah of batteries. Redarc and 12 volt shop agree 30a. Original was 30a and i've seen 25a go in often and absolute max 28a one day about 6 years ago.
Baz421 said
04:19 PM Nov 1, 2019
I still tnink the mppt started charging earlier in morning, not a lot of amps but charging. Get off the floor now,,,lol
iana said
07:44 AM Nov 2, 2019
I have learnt that it is most important to disconnect the solar before disconnecting the batteries, I you don't there is a danger of damaging the regulator.
On the contrary, since we have changed over to a MPPT controller, we have plenty of power.
T1 Terry said
10:55 AM Nov 2, 2019
iana wrote:
I have learnt that it is most important to disconnect the solar before disconnecting the batteries, I you don't there is a danger of damaging the regulator. On the contrary, since we have changed over to a MPPT controller, we have plenty of power.
Did you rewire the solar to a series connection for the MPPT controller?
T1 Terry
dorian said
01:12 PM Nov 2, 2019
It would really help to see hi-res photos of the innards. A lot of this gear uses fake parts. Several of us techs would be keen to see a teardown.
iana said
03:58 PM Nov 2, 2019
Terry ---- Yes.
Baz421 said
11:12 PM Nov 2, 2019
Dorion I'll see how it opens when I fit the new one. Cheers
T1 Terry said
04:47 PM Nov 4, 2019
T1 Terry wrote:
iana wrote:
I have learnt that it is most important to disconnect the solar before disconnecting the batteries, I you don't there is a danger of damaging the regulator. On the contrary, since we have changed over to a MPPT controller, we have plenty of power.
Did you rewire the solar to a series connection for the MPPT controller?
T1 Terry
Because the solar was rewired from parallel to series so the voltage went up and the current went down and it result in better charging from the existing solar shows the problem was not the choice of controller but rather the poor wiring from the solar to the controller. A common factory wiring problem due to the fact they seem to think a single 100w panel is more than anyone could ever need, no point in wasting money on heavier cable or more runs of the bootlace size cable they consider to be plenty for any and every application.
Glad it is working well for you, did you increase the size of the cable from the new controller to the battery?
T1 Terry
iana said
10:40 PM Nov 4, 2019
Hi Terry, I don't want to steal this thread, but to answer your question the solar side of the wiring was 6mm, but was a long series of runs. The supply from the regulator to batteries was upped to 8mm.
T1 Terry said
03:31 PM Nov 5, 2019
iana wrote:
Hi Terry, I don't want to steal this thread, but to answer your question the solar side of the wiring was 6mm, but was a long series of runs. The supply from the regulator to batteries was upped to 8mm.
To give you an idea of the cable size required, 6 B&S (13.5mm sq) can carry up to 40 amps over 5 mtrs without voltage drop becoming an issue. Was the 6 mm wire the size of the hole required to push it through? That is known in the trade as 6mm auto cable, 4.35mm sq conductor, a far cry from the 13.5mm sq conductor required to do the job properly.
T1 Terry
Baz421 said
08:26 PM Nov 21, 2019
FOR DORIAN - INSIDE THE OLD MPPT SOLAR CONTROLLER.
-- Edited by Baz421 on Thursday 21st of November 2019 08:32:30 PM
Thank you. The innards look substantial -- I can see why it wasn't cheap. That said, I can't find a single reference to "guike" capacitors on the Internet, although their specs look impressive.
I see that the unit has two coils. Perhaps one is for buck and the other for boost mode. It would make for an interesting teardown for someone who has the time and inclination (maybe DeBe ?).
DeBe said
10:24 PM Nov 22, 2019
With 14 switching devices on that board i would be checking both sides for cracks in the solder around each lead. The pictures arent realy clear enough but i picked one that was & marked a relavent lead. Dry solder joints (cracking) is a common fault on PCBs with solid state switching.
Thanks. It has gone back to manufacturer to investigate 2nd almost identicle failure. Your comments make sense for this one as it was so intermittent, ie didn't work on hot day but worked fine the next day that was cool, about 20 C cooler.
DeBe said
01:40 PM Nov 23, 2019
This is what you look for. This is a Generator AVR i repaired. The owner did say it was intermittent for some time until it eventualy stoped working.
-- Edited by DeBe on Saturday 23rd of November 2019 01:45:15 PM
In a post about Sep18 I said I changed to MPPT controller, as I stuffed my original PWM controller (silly me)
Well have had 2 MPPT's from Jaycar - Powertach 3731,,, 1st one lasted till Easter 19 and packed it in, wouldn't charge.
New one has just started charging one day and not the next.
HAVE ORDERED NEW REDARC PWM, spoke to techie he was VERY helpfull. Back to a simple pwm close the cupboard and monitor in morning and afternoon,, hands off like did for 11 years with original el cheapo pwm.
Terry T1 you were right, I eat humble pie. My MPPT experiment is over.
Well, I've climbed back off the floor and back on the chair, but still a wobbly on the legs
What price for the Redarc unit and how many amps does it handle?
T1 Terry
On the contrary, since we have changed over to a MPPT controller, we have plenty of power.
Did you rewire the solar to a series connection for the MPPT controller?
T1 Terry
It would really help to see hi-res photos of the innards. A lot of this gear uses fake parts. Several of us techs would be keen to see a teardown.
Because the solar was rewired from parallel to series so the voltage went up and the current went down and it result in better charging from the existing solar shows the problem was not the choice of controller but rather the poor wiring from the solar to the controller. A common factory wiring problem due to the fact they seem to think a single 100w panel is more than anyone could ever need, no point in wasting money on heavier cable or more runs of the bootlace size cable they consider to be plenty for any and every application.
Glad it is working well for you, did you increase the size of the cable from the new controller to the battery?
T1 Terry
To give you an idea of the cable size required, 6 B&S (13.5mm sq) can carry up to 40 amps over 5 mtrs without voltage drop becoming an issue. Was the 6 mm wire the size of the hole required to push it through? That is known in the trade as 6mm auto cable, 4.35mm sq conductor, a far cry from the 13.5mm sq conductor required to do the job properly.
T1 Terry
FOR DORIAN - INSIDE THE OLD MPPT SOLAR CONTROLLER.



-- Edited by Baz421 on Thursday 21st of November 2019 08:32:30 PM
Thank you. The innards look substantial -- I can see why it wasn't cheap. That said, I can't find a single reference to "guike" capacitors on the Internet, although their specs look impressive.
I see that the unit has two coils. Perhaps one is for buck and the other for boost mode. It would make for an interesting teardown for someone who has the time and inclination (maybe DeBe ?).
-- Edited by DeBe on Saturday 23rd of November 2019 01:45:15 PM
Thanks. It's in Jarcars hands now,,,, see if I get some feedback?