Solar wiring question and TriMetric installation advice

[sclifrickson]

Originally Posted by rbryan4

Right, but that's a safety feature to protect the inverter - not 12V output.

Sure, I understand that. I was just offering this as evidence that when solar is putting out higher voltages, the rest of the systems aren’t necessarily at 12V nominal, so concern about over voltage damage to other components is a valid concern.

[rbryan4]

Originally Posted by sclifrickson

Sure, I understand that. I was just offering this as evidence that when solar is putting out higher voltages, the rest of the systems aren’t necessarily at 12V nominal, so concern about over voltage damage to other components is a valid concern.

Yes, I understood. My point is that the battery output (not the solar charge controller or any other device) should remain unaffected by charge input.

Not sure what is meant by "when solar is putting out higher voltages." The charge input is regulated by the charge controller, right?

[paulk]

Originally Posted by fudge_brownie

Does the Victron require much configuration? The user manual for my TriMetric is full of notes and comments, the manual is a difficult read but an easy program. Very detailed information comes out of the TriMetric, but the only one everyone uses is the display set to percent. It tells it all.

I have an inline fuse on my TriMetric, since it is a direct connect to the battery I have to pull the fuse over winter to prevent battery drain. I do not recall having to enter my parameters in the spring, it is probably an EPROM that retains the settings when without power.

Sorry if I provided incorrect information on the Trimetric. I don't own one, but I thought from previous discussions that it had volatile memory. Perhaps that was only in reference to the history (things like max voltage observed, number of charge cycles, etc)

I didn't find the setup difficult, but I'm a techie kind of person who enjoys tinkering these kinds of setups. The only thing I would say you would really want to get right is to set the total battery capacity correctly, which is needed to compute the percentage of the capacity that has been drained. There are a lot of other options for things like low/high battery alarms and other things. I went through them all and set them the way I liked, but I wouldn't call that necessary.

[rbryan4]

Originally Posted by paulk

I don't understand this statement. Is there some sort of voltage regulator in the system that I'm not aware of?

Not a voltage regulator per se (WFCO and others have "over voltage protection" in their units but that is likely only for shore power), but power is still being distributed via the 12v bus in the power center, and I have not seen a direct 1 to 1 correlation between input charging voltage and output voltage. I've measured output slightly increase during an absorption cycle, but nowhere near the actual input which my charger provides. Besides, RV components (at least decent ones) are typically designed to accept the higher voltages. I've not had a single 12v component failure in over 3 years, and I routinely charge my dual 6V batteries at over 15 volts during absorption.

My concern would remain making sure you're providing adequate charging voltages to the batteries, vs concern about things like LED fixtures. Just my two cents.

[paulk]

Originally Posted by rbryan4

Not a voltage regulator per se, but power is still being distributed via the 12v bus in the power center, and there is not a direct 1 to 1correlation between input charging voltage and output voltage. I've measured output slightly increase during an absorption cycle, but nowhere near the actual input which my charger provides. Besides, RV components are typically designed to accept the higher voltages. I've not had a single 12v component failure in over 3 years, and I routinely charge my dual 6V batteries at over 15 volts during absorption.

Usually during bulk charging you won't see high voltages in the system initially since the battery will be sucking in as many amps as it can take from the charger. After some time as the battery charges up, the voltage will continue to rise until it hits 14.4, 14.8, 15.3, or whatever the charger is set to for bulk charging. After that voltage is reached, you'll see it held for several hours until it later drops down float.

The Redarc manual actually has nice graphs showing this process on page 5:
https://www.redarc.com.au/Content/Im...n%20Manual.pdf

On the GoPower solar charge controller I noticed it at 14.9-ish volts during random parts of the day on a fully charged battery. It shouldn't be at this high a voltage as much as I think it was. At most it should be putting that much voltage out for an hour or two every once in a blue moon. I think though that solar chargers are designed to push as much current into the batteries as possible, since people will complain if their batteries aren't topped off at the end of the day, hence high voltages.

I think the WFCO is much more reasonable about staying at 13.2 volts most of the time and raising up when needed for bulk. They don't have an equalization stage though, as we've discussed in other threads. If I had both shore power or solar, I'd much rather use the shore power to charge the batteries as it doesn't have to worry about intermittent sunlight and therefore doesn't need to be designed to push in every last amp into the batteries during the daytime, which requires higher voltages.

[rbryan4]

Yep, completely agree. Once that internal resistance increases during bulk, the only way to get them to a full charge the rest of the way is with a higher voltage.

[sclifrickson]

Originally Posted by rbryan4

Yes, I understood. My point is that the battery output (not the solar charge controller or any other device) should remain unaffected by charge input.

Not sure what is meant by "when solar is putting out higher voltages." The charge input is regulated by the charge controller, right?

Solar controller output voltage is variable, as I’m sure you know. “Solar putting out higher voltages” simply refers to times during the charge cycle when those voltages are higher than at other times. An equalization charge in cold weather will approach 16V, which is what Interstate calls for in their charging specifications.

I share Tom’s concern that these higher voltages have the potential to harm other system components if they’re not able to handle such voltages, and I offered my observations with my inverter shutting down at these voltages to support my assertion that overall system voltages are not maintained at 12V nominal, but rather will exceed that when the solar system is putting out higher voltages. Now I want to put my multimeter on other things during Absorption phase to see what’s actually getting to the refer, for example, or a light fixture.

[rbryan4]

Originally Posted by sclifrickson

Now I want to put my multimeter on other things during Absorption phase to see what’s actually getting to the refer, for example, or a light fixture.

That's a good plan. The highest I ever measured during an absorption cycle was 14V, although my charge controller was putting out much higher.

[sclifrickson]

Originally Posted by rbryan4

That's a good plan. The highest I ever measured during an absorption cycle was 14V, although my charge controller was putting out much higher.

Outside temp is currently 41F. Solar controller is in Absorption stage and shows 15.4V output (temperature compensating BlueSky controller). Just popped cover off the pancake light over the sink and measured voltage using a Fluke 117 True RMS Multimeter at 15.21V [emoji848]

[rbryan4]

Originally Posted by sclifrickson

Outside temp is currently 41F. Solar controller is in Absorption stage and shows 15.4V output (temperature compensating BlueSky controller). Just popped cover off the pancake light over the sink and measured voltage using a Fluke 117 True RMS Multimeter at 15.21V [emoji848]

That's alot closer to the input voltage than I've ever had.

But, great to know your batteries are getting the proper charge voltage. Few are.

[sclifrickson]

Originally Posted by rbryan4

That's alot closer to the input voltage than I've ever had.

But, great to know your batteries are getting the proper charge voltage. Few are.

True. I’ll risk frying cheap LED’s if it means my expensive 6V batteries are healthier, fully charged, and therefore longer lived.

But I do worry a bit about other appliances. I’ve just never gone to the trouble to look up input range for the rest of the stuff onboard. Refer, Maxxfan, etc.

[tdf-texas]

Originally Posted by sclifrickson

Outside temp is currently 41F. Solar controller is in Absorption stage and shows 15.4V output (temperature compensating BlueSky controller). Just popped cover off the pancake light over the sink and measured voltage using a Fluke 117 True RMS Multimeter at 15.21V [emoji848]

I measured the battery voltage using a Fluke multimeter with my Victron solar charger in equalization mode and it was 15.8 volts. The battery charge level is at 100%. Measuring the voltage at the LED light above the dinette gave me 15.6 volts. Measuring the voltage at the fridge terminals also gave me 15.6 volts with the fridge off so I expect that all the 12v devices in the trailer are getting this voltage.

I turned on the GoPower inverter and it went into overvoltage alarm and shut down.

This is probably not good for the 12v devices. Granted with the devices that pull a good deal of current, the voltage drop will lower the voltage seen by the device. But up to 15.6 volts idle voltage could harm the electronic circuitry.

I have now turned off automatic equalization on the Victron solar charger.

[sclifrickson]

Originally Posted by tdf-texas

I measured the battery voltage with my Victron solar charger in equalization mode and it was 15.8 volts. The battery charge level is at 100%. Measuring the voltage at the LED light above the dinette gave me 15.6 volts. Measuring the voltage at the fridge terminals also gave me 15.6 volts with the fridge off so I expect that all the 12v devices in the trailer are getting this voltage.



This is probably not good for them. Granted with the devices that pull a good deal of current, the voltage drop will lower the voltage seen by the device. But up to 15.6 volts idle voltage could harm the electronic circuitry.



I have now turned off automatic equalization on the VIctron solar charger.

It’s a conundrum. Because those higher voltages are what Interstate says you need to keep their batteries happy and healthy. If every 12v doohickey in the trailer were safe up to 16V then this would be a non-issue. But I’m suspicious that not everything is rated that high. Okay, I’m going to go look up fridge specs...

[tdf-texas]

Originally Posted by sclifrickson

It’s a conundrum. Because those higher voltages are what Interstate says you need to keep their batteries happy and healthy. If every 12v doohickey in the trailer were safe up to 16V then this would be a non-issue. But I’m suspicious that not everything is rated that high. Okay, I’m going to go look up fridge specs...

I know that the LED lighting is not - that is what started this thread:
http://www.escapeforum.org/forums/f9...hts-14152.html

[sclifrickson]

Originally Posted by sclifrickson

It’s a conundrum. Because those higher voltages are what Interstate says you need to keep their batteries happy and healthy. If every 12v doohickey in the trailer were safe up to 16V then this would be a non-issue. But I’m suspicious that not everything is rated that high. Okay, I’m going to go look up fridge specs...

Edit: Bummer, the manual says voltage range on my RM2554 is 9.5-15V. If I don’t operate it on DC does this matter? We only ever use AC or LP.

I don’t see specs in the Maxxfan 7500K manual.

[sclifrickson]

Originally Posted by sclifrickson

Edit: Bummer, the manual says voltage range on my RM2554 is 9.5-15V. If I don’t operate it on DC does this matter? We only ever use AC or LP.

I don’t see specs in the Maxxfan 7500K manual.

Edit: Bummer Part 2 - I just called Airxcel tech support, and they informed me that voltage range for my Maxxfan is 11-13.6V, or possibly up to 14.4 volts if we have one of the “new boards”. [emoji19]

I wonder how hard it would be to wire in a voltage regulator...?

[tdf-texas]

Originally Posted by sclifrickson

Edit: Bummer Part 2 - I just called Airxcel tech support, and they informed me that voltage range for my Maxxfan is 11-13.6V, or possibly up to 14.4 volts if we have one of the “new boards”. [emoji19]

I wonder how hard it would be to wire in a voltage regulator...?

It can be done but it's going to take some work as Escape mixes the devices on the 12v runs. Take a look at the link - Ken (wetzk) has been working on this problem already.
http://www.escapeforum.org/forums/f9...tml#post276228

[padlin]

Don't have the numbers anymore, but when I first installed my solar controller I had checked all the large 2014 appliances for max allowable dcv, all were 16dcv or above. I did not check lights, the fan, and any other small stuff.

[paulk]

Originally Posted by sclifrickson

I wonder how hard it would be to wire in a voltage regulator...?

Probably not too hard, at least with the WFCO. Brian-B-P pointed out in another thread that the converter and loads were on different terminals inside the WFCO, so all that would be required would be to take a wire out of the WFCO to the battery and one side of a voltage regulator, and bring second wire into the WFCO from the other side of the voltage regulator.

Here's the thread:
http://www.escapeforum.org/forums/f3...8343-4.html#36

[tdf-texas]

Originally Posted by paulk

Probably not too hard, at least with the WFCO. Brian-B-P pointed out in another thread that the converter and loads were on different terminals inside the WFCO, so all that would be required would be to take a wire out of the WFCO to the battery and one side of a voltage regulator, and bring second wire into the WFCO from the other side of the voltage regulator.

Here's the thread:
http://www.escapeforum.org/forums/f3...8343-4.html#36

The 12v panel in the WFCO is a 40 amp panel. 40 amp 12v voltage stabilizers are rare and expensive. Not all the 12v circuits need regulating but the ones that do and the ones that don't are wired together. Separating the ones that need regulation so a smaller voltage stabilizer could be used becomes the problem.