Overvoltage warning on solar charger

[Hickers]

Given problem only occurs with full sun on both panels it must be the output that is the key to the problem though Victron maintain that the controller can accept higher wattage without issue. As clouds pass over or the boat swings shading one the panels the wattage reduces and the cycling stops. The installer is going to contact Outback and Victron to see if they can resolve the problem. I will advise the outcome! In the meantime I would ensure your controller had plenty of headroom if you are setting up a system particularly with sunpower panels which deliver in excess of their rated output.

 

[Insequent]

I'm a fan of Victron stuff, and believe that they usually have conservative specs and tolerance for above spec operation for short periods. So here is my latest guess:
what you have is an MPPT 100/30. They share a common spec sheet after all. Someone just stuck the wrong label on the outside of yours! :lol:

At least it explains why you have to be below 500W from the panels to avoid cycling.

 

[Hickers]

That would be great no cost fix, two in a row though???

 

[Insequent]

Probably just fantasy, but I can't believe a Victron product not being able to get any where near spec. Rated at 700 W and craps out at 500 W? Something really wrong. Two in a row? Are they assembled in China without adequate QC? Local manager skimping on component sizes to pocket extra money? More fantasies..... Of course there may be a quite simple explanation that none of us armchair guru's can figure out.

 

[Pgitug]

Just a side note. We had two large solar panels on the pilot house roof. When we bought the boat. I guess for trips to the Bahamas. I got the hell shocked out of me while working on our 12VDC wiring. Long story short, the solar panel controller had failed and was cooking our systems and our batteries. Ripped out the solar system, sold the panels and replaced the batteries. We do not anchor out for days on end so why the heck deal with the problems of having solar on the boat?

150# on the cabin top
Can't clean under the panels
Just another system to mess your electrical up

I know I'm the ultra conservative boater but Hey, that's just me..

 

[Hickers]

Ouch! Understand, less system = less problems.
For us living on anchor much of the time as we cruise the Queensland coast and running 3 fridges and a freezer it cuts our genset run time by at least 30%, 50% on a good solar day so worthwhile for our boating.

 

[stone beach]

Ouch! Understand, less system = less problems.
For us living on anchor much of the time as we cruise the Queensland coast and running 3 fridges and a freezer it cuts our genset run time by at least 30%, 50% on a good solar day so worthwhile for our boating.

1. Are you sure your original controller was replaced? Not that your original unit just went on a round trip??
2. Check you have selected the correct parameters for your installed batteries, particularly type & size.
3. Check for a bad connection or cable on output side of controller as others have suggested but as problem only occurs above a cetain value of load (if set up is correct) it sounds like a controller fault.
4. Next time it happens pull fuse on the controller, isolate battery bank and check battery voltage after say 20 mins. As the controller is trying to push 40A into them it thinks they are down....are they?? (Any other chargers you may have should also be off during this period)
5. I cant see the photos you posted...just blanks??? Interested in operating parameters.

 

[stone beach]

From data sheet

Flexible charge algorithm
Fully programmable charge algorithm (see the software page on our website),
and eight pre-programmed algorithms, selectable with a rotary switch
(see manual for details).

Extensive electronic protection
Over-temperature protection and power derating when temperature is high.
PV short circuit and PV reverse polarity protection.
PV reverse current protection.

How hot is the controller? Where is it located?

 

[Hickers]

Hi,
The 100/50 VictronConnect mppt controller is located in the lazerette, ambient is 30 c and controller temperature is 48 c, rated for full power to 60c so I think that's not the issue. Battery external case temperature is 25/26 c.

In terms of battery bank the house batteries are 760 amps of agm, float 13.8 and absorb 14.4. House load is a constant 15 to 30 amps for fridges, freezer, pumps etc.
Once house bank reaches 13.7 vsr's connect in start, genset, windlass and thruster batteries which is over 1400 amps so difficult to overcharge them.
I have tried running the batteries down but still get the cycling at a rate of once every 6 seconds once panel watts exceed 500/550.

On the genset or engines batteries will take 120 amps easily at bulk charge rate.

I know it's a new unit as I fitted the replacement!!

Cables are doubled (?) and have sufficient capacity to carry 100 amps according to the installer.

I believe the controller can't cope with the panel output in spite of the panels being within the 100 volt/50 amp rating.

The problem is back with the supplier and installer at the moment who are both saying it should have the capacity and even if it didn't it tops out the charge rate not reduces it to zero!! We will see but unless they find another solution I will be wanting a higher rated controller to try!!

What a mystery! Thank you for taking the time to reply.

 

[stone beach]

Hi,
The 100/50 VictronConnect mppt controller is located in the lazerette, ambient is 30 c and controller temperature is 48 c, rated for full power to 60c so I think that's not the issue. Battery external case temperature is 25/26 c.

In terms of battery bank the house batteries are 760 amps of agm, float 13.8 and absorb 14.4. House load is a constant 15 to 30 amps for fridges, freezer, pumps etc.
Once house bank reaches 13.7 vsr's connect in start, genset, windlass and thruster batteries which is over 1400 amps so difficult to overcharge them.
I have tried running the batteries down but still get the cycling at a rate of once every 6 seconds once panel watts exceed 500/550.

On the genset or engines batteries will take 120 amps easily at bulk charge rate.

I know it's a new unit as I fitted the replacement!!

Cables are doubled (?) and have sufficient capacity to carry 100 amps according to the installer.

I believe the controller can't cope with the panel output in spite of the panels being within the 100 volt/50 amp rating.

The problem is back with the supplier and installer at the moment who are both saying it should have the capacity and even if it didn't it tops out the charge rate not reduces it to zero!! We will see but unless they find another solution I will be wanting a higher rated controller to try!!

What a mystery! Thank you for taking the time to reply.

Controller is too hot on the data sheet I looked at max temp for full load is 40

Panel output is not an issue. Its not how it works

 

[stone beach]

Controller is too hot on the data sheet I looked at max temp for full load is 40

Panel output is not an issue. Its not how it works

Data sheet:-
to +60°C (full rated output up to 40°C)

 

[DavidM]

stone beach:


That 40 deg C spec for full rated output is ambient temperature, not the controller case temperature. But you may have a point. Even though Hickers reports 30 deg C ambient, that may be too hot for full output so the unit cycles.


How about directing a fan on the controller and see if that stops the cycling?


David

 

[twistedtree]

stone beach:

How about directing a fan on the controller and see if that stops the cycling?


David

Great idea, and very easy test to try.

 

[C lectric]

In addition to the fan can you prop open a door or locker? If the cavity the controller is in is too small or to tightly closed then the outdoor ambient may be fine but the cavity ambient may not by the heat the controller generates. Even with a fan it may need to have that heat forcibly exited, not just circulated.

 

[stone beach]

Been searching for panel info. covering your panels.
For what may be a similar sunpower panel voc is 68.2 ?? Which is way more than your controller can support with 2 panels in series so maybe I am looking at the wrong data....or maybe you have unmatched system components??

Presume your 2 panels are connected in series?

There is usually a big label on the back of the panel with tech data. If you post a photo of that you might get better comment !!

Also, I dont understand how your vsr's are wired....What are these doing when trip cycling is occurring?

If they are as you describe and if sensing house bank then I cant imagine how the controller (or the vsr's) can deal with that situation???
Finally, you didnt answer my set up or battery voltage question ??
Cant help much with only part info.

 

[Hickers]

Hi everyone, problem solved, nothing to do with the controller, the installer fitted an auto reset breaker in the wires to the house battery from the controller, this was overheating, tripping and then resetting in anything much over 35 amps although it was rated to 50 amps. Taking it out of the system saw the cycling problem disappear and the controller happily deliver 50 amps per hour and the house bank showing steadily increasing voltages over the day. The electrician is sending me a larger capacity breaker.
Thank you all for your contributions, this problem was very frustrating and I'm glad that in the end the fix was/will be easy.

Now on to sorting the low voltage at the fridge.

Boats, don't we love them!

 

[Insequent]

Nice work to get it sorted, and thanks for telling us about it.

 

[BruceK]

Hickers,great you solved the problem.
What was the intended function for the breaker? I have an inline fuse fitted close to the battery in my much lower output array, pretty sure I saw it on a schematic published online, as a safety thing.

 

[Hickers]

Jim said It's there to protect the circuit in case there is a short in the charging cables, it was fitted into the red wire just prior to the battery terminal.