How to interpret Ah reading on EPever MT-1

[hornsofallign]

Hi folks, I'm new to the forum, though have been a regular anonymous visiter.

Please can I ask for advice about the display on the solar meter (an EPever MT-1) on our 2015 Adria MH? The meter reports from the low cost EPever duo controller, which is fed by a 1040mm x 600mm panel, with the charge going into an LFD90 battery via an EBL 226.

On the solar tab of the MT-1, there is a figure for total Ah. Is this figure the total Amp hours the solar controller has sent to the EBL, or is it reporting the total amp hours the solar controller 'received' from the panel. The total figure seems very low to me ( < 4Ah / day) and the spot amps measure is rarely above 1.3 - though the meter says it has peaked at 6 (though never when I'm looking at it).

The MH is left on EHU most of the time, so I wondered if the MT-1 is just reporting a top-up value of Amps it's actually 'used', and it's so small because the battery is already full.

If it's not a top-up, then the output from this setup seems less than useless ( < 4 Ah / day) and I presume is broken in some way.

Any help interpreting the numbers would be good, as I couldn't tell form the manual what it meant.

 

[Guigsy]

If the battery is full, then the solar controller won't be pushing many Ah into the battery. It'll just be providing a trickle 'float' charge to the battery.

If you want to see some good watts captured, you need to unplug for a bit and run down the battery or run something with some load.

EDIT: MoHo is on the driveway and not plugged in. Just checked my Victron app. I'm getting ~10Ah per day at the moment. That's enough to maintain the battery charge level.

 

[denisejoe]

What is your battery voltage and your daily usage ?

if on hookup the solar wont be of any use take of hookup then see what happens your battery can only hold so much charge same as how much water can go into a cup.

 

[hornsofallign]

Thanks Guigsy / DeniseJoe. The battery is typically 13.8 upwards, so the float / trickle feed idea makes sense, and suggests the setup isn't broken.

I'll do a test tomorrow with a load on the battery and no EHU.

many thanks.

 

[Reallyretired]

I have the same meter and the solar output is tiny if the batteries are fully charged which is as I would expect.
Try without ehu and discharge the batteries a bit and you should see a big increase.

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

If you want to see what the solar is doing disconnect the EHU then run the battery down to about 75% then you can observe what the solar is doing.

 

[hornsofallign]

It's a clear sunny day in the NW, so I disconnected EHU this morning and turned the fridge onto 12v 2 hours ago. It's a dometic RMD 8505 which according to the manual is 170w, so I think at 12v draws unto 14amps.
The battery is now showing 12.2v and the icons on the meter show it quite empty. The meter says solar is generating about 1.4 amps.
and the Ah total has gone up 2, in two hours.

I'm reluctant to carry on the test, as I think the fridge will have killed the battery in the next couple of hours.

Any thoughts?

 

[Guigsy]

It sounds like your solar is delivering well below spec. However, a tiny shadow, even from something like an aerial or just something shading the tiniest edge will cause the output to plummet.

I'd turn off the fridge as the battery is definitely discharged enough to 'bulk' charge with the solar. I'd then watch it for the next couple of hours. Solar noon isn't until 1pm BST.

 

[autorouter]

You don't say the wattage of the panel, but from the size I'm guessing it's 100W or 120W. That should be giving you 30Ah or so on an average day, and maybe 40Ah of more on a good day. 4Ah is a bit low, I think, even for NW England. I'd be expecting 5A or 6A for a few hours from the controller.

 

[Lenny HB]

Are your panels clean as if there is a layer of dirt or sand can considerably reduce the output.

^{_{Subscribers  do not see these advertisements}}

 

[hornsofallign]

I don't know the spec of the panel, but it's size is close to a sunstar 115w panel.
Solar noon and getting 1.3 amps
They are a dit dusty so will give them a clean. fingers crossed

 

[Lenny HB]

At that time of day if its a bright clear sky I would expect 4 amps or more.

 

[Guigsy]

Sounds like a faulty cell within the panel.

 

[cyberyacht]

A panel that size is certainly not going to keep up with a fridge. My 3 x 100w would barely cope in the middle of the day.

 

[hornsofallign]

Sounds like a faulty cell within the panel.

Cleaning the van today I noticed these black and green markings inside the panel. There no other marks on the panel like it

Does this look like something is burned out?

^{_{Subscribers  do not see these advertisements}}

 

[Raul]

Cleaning the van today I noticed these black and green markings inside the panel. There no other marks on the panel like it

Does this look like something is burned out?

Yep, green is corrosion of the conductor. That indicates it’s been faulty for some time to go green. You got burn out spots that creates high resistance and impeding the amps flow. Throw the panel away and renew. There is nothing you can do to the EV encapsulation layer, even if you repair the track.
Best to go for a new modern rigid panel.

That spot is a fire hazard as well, after a damp day followed by a bright sunny sky.

 

[hornsofallign]

Oh dear. Will disconnecting the cables off it remove the fire risk?