House Battery

[c21]

Yes, the readings are the same for my 1,000w Magnum in my 14 AI. Anxious to hear what you find out Sam!

[toskeysam]

OK....Tom Scavera at Magnum Energy replied to me this morning. "Yes your setup has all four modes of charging." Also said..."You may not see full charge unless you spend a lot of time at the remote".... Kinda makes sense...
Also, the only way I am going to improve my charging is to have the temp sensor installed. I did order one last week. It is sitting here, in a bag, waiting for me to decide who is going to install it.

[c21]

Thanks for obtaining and sharing the Magnum Invertor info Sam. Also, electrically challenged me installed the temp sensor on my rig and it was very easy. My batteries are in a steel box under one of the twin beds, I drilled a hole near the bottom of the box, used a rubber grommet with liberal silicone sealant around the line then had my phone guy attach a new RG connector (I cut the installed one off to facilitate feeding the line thru the grommet). The RG then plugs into the invertor.
Bill

[toskeysam]

Winter weather here in Tennessee is keeping me from doing the probe installation myself. Cold, rainy, just plain crappy weather. If I had a good break, would tackle it. May wait until spring.

[UKDUDE]

Thanks from me too, Sam, for clearing this up with Magnum.
I guess I should install a temperature sensor too.

[c21]

I ordered my battery temperatur sensor from a Company in Arizona called Tekris Power Electronics, Inc (wwww.tekrispower.com). You can call them at (877) 483-5747. I spoke to Shari and she is sold me one for $27 with free shipping. The Magnum part number is ME-BTS-15.

[lewster]

GOOD MOVE!

Temperature sensing is very important, especially in high ambient temperatures, as it will keep your batteries from being overcharged. Don't forget that the prescribed voltages for 3 stage charging that everyone speaks of are measured at 77ºF. The higher the temp, the lower the voltage that is required for effective 3-stage charging.

[Boxster1971]

Originally Posted by lewster

GOOD MOVE!

Temperature sensing is very important, especially in high ambient temperatures, as it will keep your batteries from being overcharged. Don't forget that the prescribed voltages for 3 stage charging that everyone speaks of are measured at 77ºF. The higher the temp, the lower the voltage that is required for effective 3-stage charging.

Lewster,
I noticed recently that the AGM 1 Battery Type setting for my Magnum MMS1012 does not quite match the Lifeline Float charge requirements. It's close but a little low, especially with any voltage drop between the Magnum unit and the batteries.

The Lifeline specification call for a Float Voltage of 13.30 +/- 0.1 volts at 77ºF. The Magnum AGM 1 Battery Type called for when using Lifeline AGMs is specified at 13.1 volts at 77ºF.

I've read several things lately that suggest many chargers newer get the batteries to desired full charge because their float voltages are wrong.

Is this significant?

[lewster]

Originally Posted by Boxster1971

Lewster,
I noticed recently that the AGM 1 Battery Type setting for my Magnum MMS1012 does not quite match the Lifeline Float charge requirements. It's close but a little low, especially with any voltage drop between the Magnum unit and the batteries.

The Lifeline specification call for a Float Voltage of 13.30 +/- 0.1 volts at 77ºF. The Magnum AGM 1 Battery Type called for when using Lifeline AGMs is specified at 13.1 volts at 77ºF.

I've read several things lately that suggest many chargers newer get the batteries to desired full charge because their float voltages are wrong.

Is this significant?

Mike,

Full charge on a Lifeline is 12.8-13.2VDC, so floating at 13.1 is not as bad as you think. One place I would look is your battery capacity, as they might only have 90-95% capacity, which would not allow them to fully charge.

On another tack, you might look at the absorption time in the charge cycle, where the majority of the charging takes place. If the setting is insufficient for the size of your battery bank, they will never truly fill to capacity.

[Boxster1971]

Thanks Lew,
I'll have a look at my battery capacity and absorption time settings.

[c21]

Lew, how does one determine the proper absorbtion time
Thanks?

[lewster]

Originally Posted by c21bill

Lew, how does one determine the proper absorbtion time
Thanks?

• Amp-hour (AH) capacity is a measurement of how many amps a battery can deliver for a specified length of time (usually 20 hours) until the voltage achieves (diminishes to) 1.75 VDC/cell at 80° F. (A 6 volt battery has 3 cells and a 12 volt battery has 6 cells, so the respective voltages are 5.25 VDC and 10.5 VDC)

Battery Bank AmpHrs Capacity
Suggested Absorb Time

200-300 A/H
60 minutes

310-500 A/H
90 minutes

510-700 A/H
120 minutes

710-900 A/H
150 minutes

910-1100 A/H
180 minutes

1110-1300 A/H
210 minutes

[c21]

thank you

[c21]

My batts are ea 80 A/H for a total of 160 so am I correct in assuming a 60 minute absorb time?

[lewster]

Yep!

[c21]

thank you Lew