Community Forums

NWIP · 02-07-2019, 10:47 AM

I have standard Newmar installed Discovery AGM batteries and no solar, without BMK. I have been reading thread reference BMK and the different settings with interest in adding to our coach. This is not mechanical and so I lack any real knowledge.

Question

I understand that equalization cycle is to equalize individual batteries. Can someone expand the need to do this, is this required for all battery types?

Thanks for trying to educate me.

redbaron73 · 02-07-2019, 11:12 AM

Here is an answer from Lifeline:

Can I equalize AGM batteries? - Lifeline Batteries

And a page from Discover:
https://discoverbattery.com/EN/batte...gel-batteries/

You will notice very conflicting information regarding can you equalize.

Lifeline says SURE - Discover says - NOPE

vsheetz · 02-07-2019, 11:56 AM

With AGM, do as your battery manufacturer recommends.

757driver · 02-07-2019, 12:18 PM

Quote:

Originally Posted by NWIP

I have standard Newmar installed Discovery AGM batteries and no solar, without BMK. I have been reading thread reference BMK and the different settings with interest in adding to our coach. This is not mechanical and so I lack any real knowledge.

Question

I understand that equalization cycle is to equalize individual batteries. Can someone expand the need to do this, is this required for all battery types?

Thanks for trying to educate me.

Bill,

What Discover recommends for AGM batteries is a “Balance” charge which is a high voltage (15.5v) BUT a very small current (1% of battery capacity) which for an 800 AH battery bank would be 8 amp charge current. A Magnum charger is an IUU charger and is not capable of this sort of charge profile. To accomplish the balance charge that Discover recommends would require an IUI charger. Not to worry, if the batteries are properly charged and kept at 100% SOC when not in use they will do just fine with a Magnum charger.

redbaron73 · 02-07-2019, 12:31 PM

Quote:

Originally Posted by 757driver

Bill,

What Discover recommends for AGM batteries is a “Balance” charge which is a high voltage (15.5v) BUT a very small current (1% of battery capacity) which for an 800 AH battery bank would be 8 amp charge current. A Magnum charger is an IUU charger and is not capable of this sort of charge profile. To accomplish the balance charge that Discover recommends would require an IUI charger. Not to worry, if the batteries are properly charged and kept at 100% SOC when not in use they will do just fine with a Magnum charger.

I had the discover AGM's in my 2013 DSDP with only the Magnum charger and the bmk. I kept them at 100% SOC except for when in use, and then only let them discharge to 60% before recharging them to 90% during boon docking.

I used the coach heavily and the batteries operated as good as new when I sold the coach this last September.

Keeping the AGM's at 100% SOC while in storage is very important, and the reason why you should install the BMK. You will also get more life if you do not allow them to be consumed beyond 50% SOC

NWIP · 02-07-2019, 08:41 PM

Quote:

Originally Posted by redbaron73

Here is an answer from Lifeline:

Can I equalize AGM batteries? - Lifeline Batteries

And a page from Discover:
https://discoverbattery.com/EN/batte...gel-batteries/

You will notice very conflicting information regarding can you equalize.

Lifeline says SURE - Discover says - NOPE

Thanks, I’ll go with recommendations oh mfg, Discover. I think BMK to see state of charge is only way to manage these batteries effectively.

96 Wideglide · 02-07-2019, 08:54 PM

Don (757driver), smartest battery, charger, dude I've ever been fortunate enough to get advice from

!!

TWINCAMSAM · 02-08-2019, 06:54 AM

SO...what exactly is BMK and how do you if you have it? Some sort of battery management is guess. I have SilverLeaf and can see aspects of the battery status.

redbaron73 · 02-08-2019, 07:09 AM

Quote:

Originally Posted by TWINCAMSAM

SO...what exactly is BMK and how do you if you have it? Some sort of battery management is guess. I have SilverLeaf and can see aspects of the battery status.

Simply put, a bmk (battery management kit) is a fuel gauge for your batteries.

A full tank is based on the amp hour rating of the battery, and then constant measurement of every amp in and out. The gauge reads from 0 to 100%, and is the only accurate way to determine battery life and state of charge.

Batteries have a limited number of cycles (0 to 100), and that number is proportionate to the amount of discharge before recharge.

For example, A battery bank can support 400 cycles from 10% to 100%, 800 cycles from 50% to 100% and 1400 cycles from 80% to 100%.

The actual number of cycles are published by battery manufacturers, and help you to know the proper way to charge and discharge your battery.

Simply put, everyone should have a BMK.

Long Island Mac · 02-08-2019, 07:36 AM

To my knowledge, when I Equalize from the MAGNUM energy panel, only the 4 house batteries are equalized. I do this 3/4 times a year, just after checking fluid levels in the batteries. During equalization, I have checked the chassis (AGM) to see if any charge going to them. They read 13.3, not the 15 plus going to the house batteries. Have replace the chassis batteries last November but the house batteries are still going strong. Initially, when new, received varying advice on equalization. My choice was 3/4 months. Seems to work for me.