Victron 100/30 voltage measurement

[swampbush]

I too am a little perplexed by Victron controllers. Whatever voltage I set for absorption the app always reports max voltage about 0.15 volts less at the controller. My Victron BMV700 measures a bit less again, depending on losses through the cable. But the controller seems very conservative and sees the absorption voltage as a max never to be exceeded so it always stays below it. With these two factors to see 14.82 at the battery measured by the BMV700 i have to set the cotroller to 15.03.

I have experimented with it for the last 12 months increasing absortion time and upping the voltage. I use a bit more water but the batteries seem to hold up better in the mornings because of it.

I also created a different victron profle with equalize at 15.07. On those quiet days with good sun I will put it in equalize until end amps drops below 1% and the battery monitor shows 14.82. Perhaps I am getting old or have too much time on my hands. Once an Engineer always an Engineer.

I have just ordered another Victron a smaller 100/30 to replace the old controller on my original panels. Newer controllers connect to the battery monitor by Bluetooth to get the voltage without any loss due to current. Be interesting to see how that compares.

[swampbush]

I forgot to add above, if the Victron won't go within 0.15 volts of its target, how important is calibration likely to be. Do Trojan batteries really care if they see 14.7 or 14.9 in the real world?

[noelex 77]

Originally Posted by swampbush

I too am a little perplexed by Victron controllers. Whatever voltage I set for absorption the app always reports max voltage about 0.15 volts less at the controller.

This is likely to be the temperature correction.

You can turn the temperature correction off with the software and adjust the set points for temperature manually. This is often the better solution as without accessories the Victron only measures the temperature at the controller not at the batteries.

[mikedefieslife]

I've just posted a question to Victron about my controller. I started having problems with the load output in that it would not turn on. Seems it was a software problem and a reset fixed it.

Now I'm having problems where the software reading a voltage of 14.2 from he batteries. They are actually 12.90. Because of the voltage error the controller will not charge and only goes into float mode with 0 current. Unfortunately a simple soft reset doesn't fix this one.

Doubt this helps anyone, but it does show that the Victron controllers aren't immune to problems.

[sailinglegend]

The link posted above is for a remote temperature compensator AND a remote voltage compensator which sits by the battery and communicates wirelessly.

If the Solar controller is mounted in or near the engine then ambient temperature could be way too high and reduce the charging voltage at the controller. If the charge current is high then losses in the wire could reduce the charging voltage even more.

Here is the link again for the remote voltage and temperature sensor for Smart Controllers - might need a software up date - only 39$ from Amazon:

https://www.victronenergy.com/blog/2...olar-chargers/

[swampbush]

Originally Posted by sailinglegend

The link posted above is for a remote temperature compensator AND a remote voltage compensator which sits by the battery and communicates wirelessly.

If the Solar controller is mounted in or near the engine then ambient temperature could be way too high and reduce the charging voltage at the controller. If the charge current is high then losses in the wire could reduce the charging voltage even more.

Here is the link again for the remote voltage and temperature sensor for Smart Controllers - might need a software up date - only 39$ from Amazon:

https://www.victronenergy.com/blog/2...olar-chargers/

Unfortunately my Victron 150/100 doesn't support vedirect and can't be upgraded to support it. I checked the serial number already.

[swampbush]

Originally Posted by noelex 77

This is likely to be the temperature correction.

You can turn the temperature correction off with the software and adjust the set points for temperature manually. This is often the better solution as without accessories the Victron only measures the temperature at the controller not at the batteries.

You are correct Noelex, I am surprised considering that it is about 25deg C this morning here and that it still has an affect as 25deg is the mid point used for compensation. Turned off temp comp and controller hit set points.
Anybody know how to extract the internal temp of the controller? Reading up it seems to take a temp reading 1 hour before it starts charging and making its own heat.

[Paul L]

Originally Posted by swampbush

You are correct Noelex, I am surprised considering that it is about 25deg C this morning here and that it still has an affect as 25deg is the mid point used for compensation. Turned off temp comp and controller hit set points.
Anybody know how to extract the internal temp of the controller? Reading up it seems to take a temp reading 1 hour before it starts charging and making its own heat.

I can't see where changing the charge setpoints based on the controller temperature can do any good at all. It has to measure the direct batt temperatures to be useful. You dump a bunch of charge into the batt during bulk and it heats up. Now the absorption temp needs to be adjusted while the controller sees none of this.

[noelex 77]

Originally Posted by swampbush

Anybody know how to extract the internal temp of the controller? Reading up it seems to take a temp reading 1 hour before it starts charging and making its own heat.

Yes that is correct, although I think from memory the temperature refrence is at wake up.

Batteries have considerable thermal mass and are often mounted close to waterline. Often the controller is mounted close to other electronic/mechanical equipment or remote from the batteries.

Adjusting the set points manually is not ideal but often it is better than using the automatic system, which relies on the controllers internal temperature.

[john61ct]

Unless you buy the add-on temp sensors Victron now sells

[FlyingScot]

Originally Posted by swampbush

You are correct Noelex, I am surprised considering that it is about 25deg C this morning here and that it still has an affect as 25deg is the mid point used for compensation. Turned off temp comp and controller hit set points.
Anybody know how to extract the internal temp of the controller? Reading up it seems to take a temp reading 1 hour before it starts charging and making its own heat.

I just asked Victron USA tech and he replied, no you can't read internal temp. I asked him to recommend it for a future update as it would save me the hassle of putting a temperature probe on top of one.

I also asked about reducing output starting at 40c and ending at 60c. He said it's pretty linear reduction in output over that range.

[noelex 77]

Originally Posted by john61ct

Unless you buy the add-on temp sensors Victron now sells

I think this will prove to be a good solution, but there are reports of problems associated with an intermittent connection, presumably caused by a lack of range from the Bluetooth signal. Perhaps Victron will release a wired version.

One significant drawback is that it makes it more difficult to tell if the controller is maintaining absorption voltage.

[dutch-barge]

Originally Posted by john61ct

Justin Larrabee is USA tech support
+1 207 3540493
jlarrabee@victronenergy.com

Yes Justin always answers the phone, or calls back, and if he can not answer it immediately out of his head, he will get the correct answer very quickly

Had a few service issues in the past 5 years I have had Victron equipment, and every time Victron came through with flying colors. ( And yes UPS takes a few days to deliver a heavy inverter)

[Yellowjacket]

Originally Posted by thomm225

This sort of thing is very common especially among engineers and technicians. Most will always over do it and take things to the nth degree … When my system goes to Float, and reads 13.6 when the default is at 13.8, It doesn't concern me

I'm not an engineer, just mildly OCD with a heavy helping of ADHD.

I spent hours, HOURS, plugging in and unplugging my three panels the other morning trying to figure out why I didn't get 33 percent more juice from the third panel (which ever one it was) when I plugged it in.

Then decided that perhaps the battery could only take so much at a time.

Had I been an engineer, I would have known the answer before I was through with my first cup of coffee, assuming I didn't know the answer before I asked the question.

[Stu Jackson]

Originally Posted by Erik Dolson

I'm not an engineer, just mildly OCD with a heavy helping of ADHD.

I spent hours, HOURS, plugging in and unplugging my three panels the other morning trying to figure out why I didn't get 33 percent more juice from the third panel (which ever one it was) when I plugged it in.

Then decided that perhaps the battery could only take so much at a time.

Had I been an engineer, I would have known the answer before I was through with my first cup of coffee, assuming I didn't know the answer before I asked the question.

Erik,

Well done. I believe that the difference, as you stated, is rather easy: The ability to analyze instead of simply flailing, is very important.

But the reality is, not everyone can do it. It's human nature.

We do, however, now have resources, like this forum and the rest of the internet, to guide those who can't.

If one won't, that's another story.


Good luck.