Solar conundrum

[GUMPY]

In the two years I have had my solar I cant ever remember seeing the voltage going to the battery being above 13.9v allthough I have seen charging currents of 15amps plus at this voltage.

The system is 500w of panels with a voltage of 43 volts through a epever 4210A  mppt controller

My suspicion is that since my batteries rarely get below 90% (measured by smartgauge in the dark)  the solar is dropping back towards float almost as soon as the sun comes up.

I have tried playing with Boost and Boost Rec voltages but to no avail.

Is there a simple way using the MT50  to force the controller into boost mode?

 

Edited April 17, 2021 by Loddon

[gbclive]

I saved this comment by Detling some time ago:

 

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. 

 

It works for me on both my Tracer MPPT and Sterling chargers.

[Chewbacka]

A quick look at the manual (assuming I’m reading the right one) shows the float voltage as 13.8v and the controller will go into boost mode (about 14.4v depending upon the setting for battery type) when the battery voltage falls to less than 13.2v.

 

Do your batteries ever go below 13.2v?

 

added - see page 21

https://www.epsolarpv.com/upload/file/1811/Tracer-AN-SMS-EL-V1.0.pdf

Edited April 17, 2021 by Chewbacka

[GUMPY]

5 minutes ago, Chewbacka said:

Do your batteries ever go below 13.2v?

Normal early morning is 12.6v

They were down below that this morning as I had the immersion on.

[GUMPY]

12 minutes ago, gbclive said:

I saved this comment by Detling some time ago:

 

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. 

 

It works for me on both my Tracer MPPT and Sterling chargers.

Just tried that, no difference

panel voltage still up in the 40's

 

Edited April 17, 2021 by Loddon

[PeterF]

Do you have power consumers taking some of the 15 Amps so in actuality the charging current is lower, which is why the voltage will not rise.

 

The other thought is that 15 Amps at 14 Volt is 210W, we are not yet into peak solar season, so that may be all you will get at the moment. Check your connectors and panels in case not all panels are supplying properly in you have several in parallel. If you have several in series, then if one is not working and they have bypass diodes then you can still get reduced power.

 

Btw, I had the same issue with my Tracer locking onto low voltage point rather than ramping up the panel voltage and a quick off/on using the isolator between the panels and controller got it sorted.

[Detling]

Is that voltage at the charger battery terminals or at the batteries themselves?. If you have used thin wire from the charger to battery there could be a significant volt drop at 15 amps, causing the solar controller to think the batteries are fuller than they are are and switch to float voltage, even though 15 amps shows they are not fully charged. Many MPPT controllers work on voltages and not current, and often have a specific time delay from reaching 14+ volts and switching to float (2 hours) so 9am at this time of year. 

[GUMPY]

Votage at battery terminals is 0.04 volts lower than the reading on the MT50, cable is a minimum of 16mm from tracer to batteries (part is 16mm part is 35mm)

Connections from the panels are in 6mm, which is one of the reasons for using 43v domestic panels to help with any voltage drop.

There is a slight difference in current between the current shown on the MT50 and the current shown on the ammeter which coresponds to the current drawn by the items that are powered on the boat at the time.

The voltmeter connected to the batteries has been checked against a reference source and the ammeter checked against a known good load.

All connections have been looked at recently as panels were taken off whilst the boat was painted last Autumn.

 

Edited April 17, 2021 by Loddon

[GUMPY]

Today for the first time, minutes after I ordered a logger to see if it was doing it whilst I wasn't there, I  saw 14.4v and 15.5 amps ?

[matty40s]

3 hours ago, Loddon said:

Today for the first time, minutes after I ordered a logger to see if it was doing it whilst I wasn't there, I  saw 14.4v and 15.5 amps ?

You see, you just know that ordering that logger makes sense.