Temperature readings around the solar controllers

[Nahbrown]

My solar controllers are mounted under the port aft bunk. Today was the first time I have seen peak production weather so I decided to take the infrared gun and get measurements while each controller was putting out max amps. The controllers are Both Victron 100/50 And were putting out 46-50 amps each for about 45 minutes prior to getting the temperature readings.

Controllers- 150F
1/2 Stained plywood Above the controllers 125F
6 gauge wire to batteries 91F


Thoughts?

[slug]

High temperatures shorten the service life of electronics

From Victron

https://community.victronenergy.com/...smartsola.html

[barnakiel]

Possible wrong install?


Are they mounted vertically?


Are vent slots oriented so that air can circulated?


Is there sufficient air draft where they are mounted?



If you have model with slots make sure these are vertical.


If you have model with plate, you can add passive radiators below.



Etc.





???


barnakiel

[SVHarmonie]

Originally Posted by Nahbrown

My solar controllers are mounted under the port aft bunk. Today was the first time I have seen peak production weather so I decided to take the infrared gun and get measurements while each controller was putting out max amps. The controllers are Both Victron 100/50 And were putting out 46-50 amps each for about 45 minutes prior to getting the temperature readings.

Controllers- 150F
1/2 Stained plywood Above the controllers 125F
6 gauge wire to batteries 91F


Thoughts?

You are missing some key data... what was the ambient temperature? Since these controllers use their own ambient temperature (at the beginning of a charging cycle) to determine charging voltage they should be located in a place where the temperature is similar the the temperature inside the battery box.

It is certainly the case that controllers like this generate heat. That heat needs to be removed. It can only be removed if the controllers are hotter than their surroundings. Soooo... the controllers will ALWAYS be hotter than the air around them.

My Victron solar controller manual states clearly that the maximum controller temperature is 60C. It generate full output until the temperature reaches 40C, and then throttle back output to control temperature.

Assuming your model carries the same spec, I’d be expecting them to be throttled down in output at those temperatures.

[noelex 77]

The Victron controllers rely on passive cooling and do run quite hot. However, your temperatures are high. Do they have much space around them?

I measured the temperature of our 100/20 units just after installation for future troubleshooting reference, but I cannot find where I wrote down the result . I will check ours again tomorrow.

For what its worth, knowing they ran hot I mounted them on some profiled aluminium. This provides a much larger air gap at the rear where the heatsink is located. I also coupled the profiled aluminium to the units with some heatsink transfer paste so hopefully the aluminium adds some useful extra area to the existing heatsink.

My controllers are also oversized. This helps reduce the temperature so it should increase reliability. The other advantage of oversized, multiple controllers is in the event of a failure the solar output can be combined to one of the working units with little loss of effective production. This is a little more expensive, but considering the total installation costs the difference is not great.

See photo below:

[barnakiel]

Originally Posted by noelex 77

The Victron controllers rely on passive cooling and do run quite hot. However, your temperatures are high. Do they have much space around them?

I measured the temperature of our 100/20 units just after installation for future troubleshooting reference, but I cannot find where I wrote down the result . I will check ours again tomorrow.

For what its worth, knowing they ran hot I mounted them on some profiled aluminium. This provides a much larger air gap at the rear where the heatsink is located. I also coupled the profiled aluminium to the units with some heatsink transfer paste so hopefully the aluminium also adds some useful extra area to the existing heatsink.

I also slightly oversized the units.

See photo below:

Super nice job with that alloy rail!


How happy are you with your 100/20?


We have 75/15 ambient 25C the controler is right now at 25C. Mounted on a plywood wall.



I am going to the 100/20 with our new panels due this summer. Pls let me know if you think 100/20 is a good choice.



b.

[noelex 77]

Originally Posted by barnakiel

How happy are you with your 100/20?

Very happy.

The initial charging algorithm when I first purchased the units was quirky, but Victron have made several firmware updates that have completely changed how the units work. The charging algorithm is now excellent and very user adjustable.

I did have a failure of one unit. This was shortly after commissioning the system, so I suspect it was just an isolated manufacturing fault rather than a reflection of the overall durability/lifespan. The defective unit was replaced under warranty.

Originally Posted by barnakiel

I am going to the 100/20 with our new panels due this summer. Pls let me know if you think 100/20 is a good choice.

What are the panel specifications?

[Nahbrown]

Originally Posted by barnakiel

Possible wrong install?


Are they mounted vertically?


Are vent slots oriented so that air can circulated?


Is there sufficient air draft where they are mounted?



If you have model with slots make sure these are vertical.


If you have model with plate, you can add passive radiators below.



Etc.





???


barnakiel

Thanks!

Vertical mount with grills vertical in the space under a bed. The batteries are co located in the same compartment. There is a vent cutout but not a fan to circulate air.

[Nahbrown]

Originally Posted by SVHarmonie

You are missing some key data... what was the ambient temperature? Since these controllers use their own ambient temperature (at the beginning of a charging cycle) to determine charging voltage they should be located in a place where the temperature is similar the the temperature inside the battery box.

It is certainly the case that controllers like this generate heat. That heat needs to be removed. It can only be removed if the controllers are hotter than their surroundings. Soooo... the controllers will ALWAYS be hotter than the air around them.

My Victron solar controller manual states clearly that the maximum controller temperature is 60C. It generate full output until the temperature reaches 40C, and then throttle back output to control temperature.

Assuming your model carries the same spec, I’d be expecting them to be throttled down in output at those temperatures.

Room temp was 86F under bed was 92F. They seemed to run at max until absorption status was Reached.


So it looks like my controllers are running 10° hotter than they should. Perhaps a fan to blow into the compartment under the bed with a temp sensor.

[barnakiel]

Originally Posted by noelex 77

Very happy.

The initial charging algorithm when I first purchased the units was quirky, but Victron have made several firmware updates that have completely changed how the units work. The charging algorithm is now excellent and very user adjustable.

I did have a failure of one unit. This was shortly after commissioning the system, so I suspect it was just an isolated manufacturing fault rather than a reflection of the overall durability/lifespan. The defective unit was replaced under warranty.



What are the panel specifications?

THX! for feedback!


I am considering their 2 x 115 mono (12V). Maybe 3 units, but I am still pondering location for this 3rd one as our boat is a 26' thing and even worse, a doubleender ;-(.



Now we have 2 x 75. Good enough but with energy I prefer a healthy overhead over just good enough.


The new regulator will need to be sized up so that should we add even more solar in a year or two I do not want to buy another regulator then.


Cheers,
b.

[noelex 77]

I have checked the temperatures for the last couple of days. The hottest seems to be the top left side of the case. The highest temperature I have seen over the short period testing period is 42° C (108° F) at 19° C (66° F) ambient.

The panels have been working hard today. One of our 335w panels managed a peak production of 394w, that is over 17% higher than the specification!

[barnakiel]

42 C does not sound excessive. Touch your laptop power brick on a hot day.


Imho test by hand from time to time and do make sure the air gets there and circulates. No air movement vastly reduces cooling of such components.


Also consider the installation as shown above on a rail. Looks a very easy mod, but one to sure improve cooling and safety.



b.

[smac999]

If you are running 50a through your 50a model maybe you need the next size up?... it has to dump the excess power somehow.