AGM charge settings

Hacker

New Member
Joined
May 8, 2021
Messages
3
Where can I find charge settings for AGMs?
Over voltage disconnect 15.9?
Charging limit 14.9?
Over voltage reconnect 14.9?
Eq-(0)
Boost charging 14?
Float charging 13.8?
Boost reconnect 13.2?
Low voltage reconnect 11.9?
Under voltage reconnect 11.9?
Under voltage warning 11.8?
Low voltage disconnect 11.7?
Discharge limit 11?
Eq duration-(0)
Boost duration 60 min?

I have the Tracer 4215BN with an MT50 and a 500ah bank of AGMs on about 300w of modules.
 

pollenface

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Nov 14, 2020
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Perth, Australia
I have set all of my epevers to "gel" charge mode for my AGM bank.

You'll find everything under the Parameters page with the MT50 and may have to set the battery type to USER to change anything.
 

Hacker

New Member
Joined
May 8, 2021
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I have set all of my epevers to "gel" charge mode for my AGM bank.

You'll find everything under the Parameters page with the MT50 and may have to set the battery type to USER to change anything.
Ok, I set to gel, mainly because there’s no equalization.
The manuals are fun to navigate because the people that wrote them know just enough english to confuse me.
The menu on the MT50 is a little challenging to learn.
I’m used to Morningstar. (Good quality products)
 

Substrate

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Never used the canned settings - go by voltage. Using "gel" settings on an agm will quickly kill them from UNDERcharge.

Example:
On my small pwm Morningstar's "sealed" setting is actually 14.1v That's only good for GEL. Agm's need higher in cyclic applications.

Looks like you may need custom user-settings,

The most important for AGM in cyclic mode is:
14.6 - 14.8v in CV/absorb. Looks like "boost" in your tracer.
13.6v - float

A 60 minute "boost duration" may not be enough in Tracer-speak, and drops to float too soon depending on your solar insolation / panel / and bank capacity. May not be enough, but don't set that to zero!

The rest should be fine. There are other ways to make sure that your agm's get charged properly via solar - it's like a chess game to do right, but this will get you away from agm-killing "gel" voltages by undercharge right out of the gate.
 

pollenface

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Location
Perth, Australia
There's a lot of people on this forum saying not to go 14.6v on an agm so i don't know.

I can't find any specific information out there.
 

Substrate

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Messages
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Location
SoCal
That's cool - do what makes sense to you.

Maybe rather than argue points, I'll offer this advice:

1) Always follow your manufacturer's specifications.
2) Use temperature-compensation "at the battery probe", rather than rely on ambient
3) If given a window of voltages to choose from, choose the higher one.

Why #3? Because we are in a solar application, where power can be non-stable and fluctuating. Choosing the higher setting allows us to get in as much as we can as fast as we can, avoiding under-charge.

This assumes that one is using NEW batteries 1st hand, and is not trying to compensate from previous owner abuse, or band-aiding poor construction, slap-together multi-battery banks with no balance, or poor initial 1st-charge techniques.

I've used agm's extensively for solar, but chess-like moves to keep them charged \properly\ is a royal PITA to do right. Costly to learn over the decades.

Quite frankly, I'd suggest the proper thing to do is move to LFP, where maintenance issues aren't so subject to interpretation. That alone is priceless.
 
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