Magnum 2812 Not Charging at Bulk Rate

When bulk charging, my ME-ARC remote control shows the charger at 13.3V. For FLA batteries, shouldn't this value be 14.6V or thereabouts? What am I missing? The same happens when the charger goes to "float". I have verified that the charger is set for the default FLA profile.

catalinajack said:

When bulk charging, my ME-ARC remote control shows the charger at 13.3V. For FLA batteries, shouldn't this value be 14.6V or thereabouts? What am I missing? The same happens when the charger goes to "float". I have verified that the charger is set for the default FLA profile.

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Without having looked at the book, it's my understanding that depending on how discharged the batteries are, you may not see the higher voltage till you get nearer the absorption stage. How big is your bank, and what is the maximum charge rate (amps) you have it programmed for?

Ted

O C Diver said:

Without having looked at the book, it's my understanding that depending on how discharged the batteries are, you may not see the higher voltage till you get nearer the absorption stage. How big is your bank, and what is the maximum charge rate (amps) you have it programmed for?

Ted

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Ted: with a 900 Ah bank and starting from 50% discharge, after 2.75 hours of charge time the charging voltage is up to 14.0. Thanks for the insight. I expect the charger to soon go into absorb mode. SOC is now approaching 90%.

Ted is right. The charge voltage cannot rise until the battery is sufficiently charged. Keep the charger on and watch the voltage - it should slowly rise until the charger gets to its set point at which time the current into the battery will slowly tail off. Depending on the size of your batter or battery bank, how discharged the battery is and the size of the charger it could take some time.


Ken

catalinajack said:

Ted: with a 900 Ah bank and starting from 50% discharge, after 2.75 hours of charge time the charging voltage is up to 14.0. Thanks for the insight. I expect the charger to soon go into absorb mode. SOC is now approaching 90%.

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Glad you resolved your problem. Best not to make a habit of discharging to 50%, it dramatically shortens battery life.

Ted

catalinajack said:

Ted: with a 900 Ah bank and starting from 50% discharge, after 2.75 hours of charge time the charging voltage is up to 14.0. Thanks for the insight. I expect the charger to soon go into absorb mode. SOC is now approaching 90%.

Click to expand...

Just a couple of thoughts....


Unless the batteries are new, do you still have a 900 AH bank? Likely not so a 50% discharge on on the SOC (depending on the device) may actually be a much deeper discharge than 50%.


The inverter/charger also has a setting for the max amps that it will provide in build charging. 900 AH is a big bank and iirc that charger has a max charge rate of 125amps. Look up your own battery specs, but I would bet that your bank could handle the full 125amps so you may want to check to be sure that it is set to deliver all of it.


Finally, look up the charging profile for your batteries and go through the process of setting a custom charge profile in your charger that matches the charge profile of your batteries.

dhays said:

Just a couple of thoughts....

Unless the batteries are new, do you still have a 900 AH bank? Likely not so a 50% discharge on on the SOC (depending on the device) may actually be a much deeper discharge than 50%.

The inverter/charger also has a setting for the max amps that it will provide in build charging. 900 AH is a big bank and iirc that charger has a max charge rate of 125amps. Look up your own battery specs, but I would bet that your bank could handle the full 125amps so you may want to check to be sure that it is set to deliver all of it.

Finally, look up the charging profile for your batteries and go through the process of setting a custom charge profile in your charger that matches the charge profile of your batteries.

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The bank is two years old. Started out at 940 Ah. The bank indeed accepts all 125 amps.

Yes it is important to know how many amps are going in while at 13.3 V. The Magnum has many settings that will limit the charger amps, which in-turn will take longer to reach absorption voltage setpoint. It would be good to check all of the settings against what you have installed. One setting that you will have to change is the AH size of your bank. The default value is only 400 AH.
I mark each setpoint in the ME-RC settings table in pencil so I can put everything back after a factory reset. It's inevitable.

O C Diver said:

Glad you resolved your problem. Best not to make a habit of discharging to 50%, it dramatically shortens battery life.

Ted

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Am aware but thanks for the reminder. I'm still educating my mate about battery management. On the other hand, whether I get five years vs seven years or more is not a concern to me. I do not have deep pockets but angsting over stretching every last bit of life out of a set of batteries is not a priorty for me. I do understand, however, that, for some, it is important. Still, I am not in a habit of abusing anything I own so I will be paying more attention to my SOC. Thanks for your advice and that of others who have offered their experience.

catalinajack said:

When bulk charging, my ME-ARC remote control shows the charger at 13.3V. For FLA batteries, shouldn't this value be 14.6V or thereabouts? What am I missing? The same happens when the charger goes to "float". I have verified that the charger is set for the default FLA profile.

Click to expand...

I had this happen when I first got my Magnum 2812. I phoned Magnum and the problem came to me turning the charger on or off with the ME-ARC. Best practice is to leave it on whether shore power is on or off. Turn off the shore power and back on again and it should correct itself. Even small discharges should go to “bulk” momentarily before going to absorb.

Jim