AGM Charging

[ViperDriver]

I know this has been discussed in other contexts but I can't find anything definitive. I just installed two AGMs on the coach side of my 2003 KSDP. I've seen discussion of needing to set the charger to a different profile for AGMs but the paperwork I got with the batteries indicate that you should bulk charge them at 14.2-14.4 volts and float charge them at 13.2-13.3 volts.

I bulk charged them at 14.4 volts and then installed. My IOTA DLS 55 converter/charger puts out 13.4 volts. It seems to me that this should be fine, that no change is required. (I hope so, since the IOTA can not be adjusted.) Can anyone advise?

[GaryKD]

Hi ViperDriver,
Your IOTA should have a RJ-11 receptical (telephone cord female receptical). You can purchase, from IOTA, a plug in module that will make your charger a 3 stage smart charger. Go here to see the device. When I purchased this device it was about $30.

There should also be a jumper cord with a RJ-11 male jack that came with your charger. If you plug the male jumper into the female charger receptical, the charger will operate at 14.2VDC. I do not recommend doing this because you need to remember to unplug the jumper to have the charger return to it's normal 13.4VDC charging.

[Mahlon]

Actually, the Iota charging voltage CAN be adjusted. There's a trimpot that's accessible from one of the ends of the unit that controls the charging voltage (so I was told by one of the Iota tech reps).

I was also told that the correct way to measure the voltage is to measure it at the house battery cables with the batteries disconnected.

Also, it's possible that your DLS-55 already has the 3-stage charging circuit built into it. If it does, you should see a green LED somewhere on it. If not, you should get an IQ4 charge controller. It's worth it.

[Gary RVRoamer]

I've used AGM batteries for several years now and have not found them to be sensitive to the charge voltage. I'm sure the manufacturers recommendation is for optimum performance, but in my experience anything close is fine. My Xantrex RS2500 doesn't have a charge profile for AGMs either (I think newer ones do, but mine is 2004 vintage). I ran an Iota DLS 90 with the IQ4 module in a previous coach with Lifeline AGM and it did the job nicely.

Perhaps I should note that the AGMs I use are are Lifelines and Trojans, two high quality brands known to stand up to abuse. Other brands might be more sensitive.

[ViperDriver]

Thanks to you all for the replies. From your answers and a little more research, I've concluded that my Lifelines should be okay with the IOTA, although I have ordered the IQ module ($25 and free shipping from bestconverter.com).

[read & learn]

Question? When I installed my 4 AGM battaries last August I went to my Xantrex RC7 remote control unit and changed my settings. I have had no problems to date.
Is there reason to believe that I may have a problem in the future or is this also a way to set up the battaries for proper charging.
Joe