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what's wrong with my solar setup


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1 minute ago, jenevers said:

Partial success but the plot thickens!

I actually have 2 identical systems of 4 panels, running side by side, each connected to a tracer controller. Both were showing low voltage readings. I disconnected the positive leads from the panels to the controllers then reconnected (as per Matty40s). One system registered 32 volts👍. The other registered 22 volts but gradually fell down to 13.7 volts👎.

Wattage. Readings are 25W👍 and 9.9W👎.  (Batteries  12.5v)

Tracers (and others) can get ‘stuck’ when the light is poor and the panels aren’t generating much, so your results are not entirely unexpected. For the one that’s dropped back down check all the connections carefully.

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26 minutes ago, jenevers said:

Partial success but the plot thickens!

I actually have 2 identical systems of 4 panels, running side by side, each connected to a tracer controller, feeding the same battery bank. Both were showing low voltage readings. I disconnected the positive leads from the panels to the controllers then reconnected (as per Matty40s). One system(A) registered 32 volts👍. The other (B)registered 22 volts but gradually fell down to 13.7 volts👎.

Wattage. Readings are 25W👍 and 9.9W👎.  (Batteries  12.5v)

30 minutes later, system A registering 14.2v 25.4W, system B registering 22.4v 40.0W......Arghh!🤔

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1 minute ago, jenevers said:

30 minutes later, system A registering 14.2v 25.4W, system B registering 22.4v 40.0W......Arghh!🤔

So that’s about 5A going into the batteries. How big is the bank?

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27 minutes ago, WotEver said:

So that’s about 5A going into the batteries. How big is the bank?

 

Post #1

 

Batteries (6 X TrojanT-105s wired to give 12V) currently reading 13.2V, so only charging at 4A going from the Tracer, but should the voltage be higher?

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My brain hurts but a thought - which controller shows the highest panel voltage? If its the one delivering the  lowest amps/watts maybe its the other controller's charging voltage is high enough to cause it to make it reduce its output or shut down - just a thought.

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1 hour ago, Tony Brooks said:

My brain hurts but a thought - which controller shows the highest panel voltage? If its the one delivering the  lowest amps/watts maybe its the other controller's charging voltage is high enough to cause it to make it reduce its output or shut down - just a thought.

See my post #27. They changed over. Initially A was 32v and B fell to 13.7v. 30 minutes later A was 14.2v and B 22.4v!!

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17 minutes ago, jenevers said:

See my post #27. They changed over. Initially A was 32v and B fell to 13.7v. 30 minutes later A was 14.2v and B 22.4v!!

Yes, but what's the charging voltage?

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2 minutes ago, jenevers said:

Hmm. I thought these controllers were well thought of.

Yeah, they are.  Worry not, at 13+V and 5A it'll treat the batts gently and eventually get them to 100%.

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Tracers can and do get stuck. They track by loading the panels reducing the voltage going into the unit and checking the current at that load. They start testing at full voltage no amps and eventually load the panels until they are just over the battery voltage. They should then return to the highest load current value, but often a Tracer controller forgets to return to the highest current point. Another feature of the Tracer series is that currents under 1.5 amps don't seem to count when trying to determine the maximum power point. The OP has 4x20 volt panels but doesn't say what wattage, so likely to be at least 200 watts total (could be over 600) which should be enough to easily exceed 1.5 amps at midday. My Tracer sometimes sticks at a panel voltage of 14.5 in the morning as the sun rises, I normally check when I get up, and as I have a switch in the panel feed I can disconnect the panels for a few seconds and things then work fine. It is a known issue but Tracer haven't changed their tracking software for years despite knowing the issue. 

Additionally if the cables from the batteries to the controller are too thin then the battery voltage plus the volt drop from the cable reaching he Tracer causes it Togo into float before the battery voltage is high enough. 

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8 hours ago, Detling said:

Tracers can and do get stuck. They track by loading the panels reducing the voltage going into the unit and checking the current at that load. They start testing at full voltage no amps and eventually load the panels until they are just over the battery voltage. They should then return to the highest load current value, but often a Tracer controller forgets to return to the highest current point. Another feature of the Tracer series is that currents under 1.5 amps don't seem to count when trying to determine the maximum power point. The OP has 4x20 volt panels but doesn't say what wattage, so likely to be at least 200 watts total (could be over 600) which should be enough to easily exceed 1.5 amps at midday. My Tracer sometimes sticks at a panel voltage of 14.5 in the morning as the sun rises, I normally check when I get up, and as I have a switch in the panel feed I can disconnect the panels for a few seconds and things then work fine. It is a known issue but Tracer haven't changed their tracking software for years despite knowing the issue. 

Additionally if the cables from the batteries to the controller are too thin then the battery voltage plus the volt drop from the cable reaching he Tracer causes it Togo into float before the battery voltage is high enough. 

I often find my panels on 14v for a couple of hours in the morning as well.

 

Would removing the positive panel feed and reconnecting wake them up as Matty suggests.

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8 minutes ago, Rickent said:

I often find my panels on 14v for a couple of hours in the morning as well.

 

Would removing the positive panel feed and reconnecting wake them up as Matty suggests.

Yep :)

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7 minutes ago, WotEver said:

Yep :)

Will give that a go then, always wondered why, even in full morning sun it took ages to move off 14v. 

The old 20a tracer didn't do that when I just had three panels wired in parallel. 

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23 hours ago, Detling said:

Tracers can and do get stuck. They track by loading the panels reducing the voltage going into the unit and checking the current at that load. They start testing at full voltage no amps and eventually load the panels until they are just over the battery voltage. They should then return to the highest load current value, but often a Tracer controller forgets to return to the highest current point. Another feature of the Tracer series is that currents under 1.5 amps don't seem to count when trying to determine the maximum power point. The OP has 4x20 volt panels but doesn't say what wattage, so likely to be at least 200 watts total (could be over 600) which should be enough to easily exceed 1.5 amps at midday. My Tracer sometimes sticks at a panel voltage of 14.5 in the morning as the sun rises, I normally check when I get up, and as I have a switch in the panel feed I can disconnect the panels for a few seconds and things then work fine. It is a known issue but Tracer haven't changed their tracking software for years despite knowing the issue. 

Additionally if the cables from the batteries to the controller are too thin then the battery voltage plus the volt drop from the cable reaching he Tracer causes it Togo into float before the battery voltage is high enough. 

Thanks for the info.👍How do you know all this????😳btw the panels are 110W each      😳

Edited by jenevers
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On 01/09/2020 at 16:46, Rickent said:

Will give that a go then, always wondered why, even in full morning sun it took ages to move off 14v. 

The old 20a tracer didn't do that when I just had three panels wired in parallel. 

3 wired in parallel have a potential current max of 15 amps, 2 wired in series have a potential current max of 5 amps. It is a lot easier to get the tracer tracking over 1.5 amps to allow it to set a max power point.  When using Tracers best to wire in parallel or as in my case of 6 panels 3 parallel strings of 2  People say that as wired in series the voltage gets higher quicker in the morning it is better, it does but only for a few minutes before the panel is at max voltage anyway, and at a time when the panels are not producing much in the way of power, current in the milliamp range, as this delays the controller finding the maximum power point it is not a good idea. Tracers are among the worst at this, but they are have a good overload margin and are reliable, all at a reasonable price.  If the wires to the batteries are to thin the controllers get tricked into thinking the batteries are full early. They measure the voltage at their terminals so if you have 13.8 v at the battery and 0.5v voltdrop on the cable the controller sees 14.3v and thinks the battery is fully charged. Use the fattest cable practical to get that volt drop down preferably to 1%, at half the controllers max current.

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15 hours ago, Detling said:

3 wired in parallel have a potential current max of 15 amps, 2 wired in series have a potential current max of 5 amps. It is a lot easier to get the tracer tracking over 1.5 amps to allow it to set a max power point.  When using Tracers best to wire in parallel or as in my case of 6 panels 3 parallel strings of 2  People say that as wired in series the voltage gets higher quicker in the morning it is better, it does but only for a few minutes before the panel is at max voltage anyway, and at a time when the panels are not producing much in the way of power, current in the milliamp range, as this delays the controller finding the maximum power point it is not a good idea. Tracers are among the worst at this, but they are have a good overload margin and are reliable, all at a reasonable price.  If the wires to the batteries are to thin the controllers get tricked into thinking the batteries are full early. They measure the voltage at their terminals so if you have 13.8 v at the battery and 0.5v voltdrop on the cable the controller sees 14.3v and thinks the battery is fully charged. Use the fattest cable practical to get that volt drop down preferably to 1%, at half the controllers max current.

Yep, just looked at controller and was pv was 14v, unplugged positive and plugged it back in and went straight up to 38v.

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Sorry to butt in but I am just about to buy a small solar system purely to keep my batteries topped up in my absence. Are some MPPT controls better than others? Is it a case of you get what you pay for?

 

If the controller falls asleep and requires a wake up call am I wasting my money when I don't expect to be at the boat for weeks during the winter months.

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