Magnum Energy ME-RC Settings with Outback 2700RE 24V

Discussion about the OutBack Energy Cell Batteries
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Magnum Energy ME-RC Settings with Outback 2700RE 24V

Post by LyssaMarieM » Fri Sep 20, 2019 10:57 am

First of all, hello to everyone! I am new here, having just purchases an 100% off-grid home that was set up by the previous owner with the following:
  • Magna-Sine 4000 Watt Sine Wave Inverter with Charger
  • Magnum ME-RC50 remote panel
  • Magnum Auto-Gen Start (configured through the ME-RC)
  • SunExtender 2v 915AH batteries (24v configuration) - Upgrading today to Outback 2700RE
  • Xantrex XW Solar Charge Controllers (2 charge controllers) managing 12 solar panels (6 215W and 6 236W set ups)
We are very much learning as we go. With taking delivery of new batteries today, we cannot afford to make a mistake with ME-RC settings as it relates to battery charging and discharging rates.

We are upgrading (today) to Outback 2700RE batteries in a 24V configuration, so QTY 12 2V batteries.

My question:
I have to configure my ME-RC for the proper settings for the new 2700RE batteries. Specifically, the settings for the:
  • Low Battery Cut-out setting that should be used to set the DC voltage level that turns off the inverter to protect the batteries from over-discharge damage (in the event my AGS fails and my generator does not kick on)
  • What is the lowest voltage setting that the batteries should be permitted to drop to before the AGS triggers the generator?
  • Absorb time charging required if my solar panels cannot produce (in winter, typically) enough power to fully charge the batteries. I think this is 390 minutes, the max allowed by my inverter
  • Float charging voltage I should configure. I believe this should be set at 27.00V based on the temperature in my basement being a constant 65 degrees
  • Is there a recommended bulk (or absorption voltage) charge setting?. I am thinking this would be the initial Charge Voltage which is 2.27V per cell or 27.24 overall
Anything else I need to consider when using the ME-RC to manage my new Outback batteries? We will eventually upgrade to the Outback Inveter but its not in the budget at this time.

Thank you everyone for your guidance!

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Re: Magnum Energy ME-RC Settings with Outback 2700RE 24V

Post by raysun » Fri Sep 20, 2019 12:02 pm

I'm sure you have the docs on the monoblocks, but here's a link if you need them: ... ttery-bank

If the system supports it, temperature compenstated charging should be used. The ambient (air) temperature and battery temperature aren't necessarily the same, especially during charging. Be cautious to minimize any overcharging of a VRLA battery, as it can lead to permanent capacity loss and shortened service life.

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Re: Magnum Energy ME-RC Settings with Outback 2700RE 24V

Post by LyssaMarieM » Sun Sep 22, 2019 2:36 pm

Thanks raysun!

I do have the manuals and, if I were using the Outback Controller it would be much easier for the inverter settings.

We do not yet have a temperature management set up, but our controller supports it. Will need to place this at the top of the list of upgrades for sure.

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My RE system: System 1:
MATE3s, 3 x Radian GS8048A,
4 x FLEXmax 100, HUB10,
2 x EnergyCell 48V 2700RE,
1 x FLEXnet DC, 4 x FLEXware ICS Plus,

System 2:
MATE3s, 2 x VFX3648,
2 x FLEXmax 100, HUB10
1 x EnergyCell 48V 2700RE,
1 x FLEXnet DC, 2 x FLEXware ICS
Location: Providenciales, Turks & Caicos Isl.

Re: Magnum Energy ME-RC Settings with Outback 2700RE 24V

Post by EA6LE-ONE » Sun May 10, 2020 7:37 am

I got the EnegyCell 2700RE 48V and I studied everything possible out there to have them set correctly.

For best results if they are used continuously you need a temperature controlled room. Try to keep the room at 24C or 75F.
Second most important will be the battery monitor.
The absorb voltage should be: 27.8V
Absorb time should be 2 hours, but for a solar system, specially when is clouded or a bit undersized, I will suggest 3 hours or more if your have a controller that can use the status of battery monitor to trigger the float.
Float voltage should be 27V and float time is also 2 hours but I leave mine 24h.

if the controller for the system can trigger the float, then should trigger it when the charge voltage is 27.8V, end amps 44A and time 10 min.

Also very important should be the daily SOC of the battery. will best to be no less of 75% to get about 6-8 years from the battery. with SOC down to 50% you will get under 3 years.

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Re: Magnum Energy ME-RC Settings with Outback 2700RE 24V

Post by provo » Sun May 10, 2020 8:03 am

Wow, that's a YUGE battery for the size of your array... do you have any plans to buy more panels? Also curious whether you have a large generator. If you draw the battery down by 14kWh daily (25% depth of discharge), a 2.7kW array operating at full sun could take 6 hours to charge back up each day with typical battery inefficiency. Do you have an idea what your daily power consumption will be, maybe based on your usage where you've been living up to now?

Also, could you tell us roughly what part of the world you live in -- I hope it's very sunny there :grin: ....

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