CactusJackSlade
Active member
Wow! Very nice write up, thank you for sharing! I will be using this thread as a reference!
I lost track of your upgrade (so many I have read about). I recall the heat issue. Did you resolve this by moving it? Putting in vents? ... or are you still living with the half power when it reaches over heated condition.Both the 60 amp Sterling DC/DC charger models have fans, but the waterproof, marine-targeted BBW1260 weighs several pounds more because of tons more heat-sinking. Agree with Hoosierrun that the 30 amp model is not adequate for almost any LTV application - certainly not for a large AH battery bank.
I was one who ran into overheat issues with installing the BB1260 under the passenger seat. I ended up moving it to be under the seat right behind the passenger seat on my twin bed. I also added a blower fan connected to a temperature controller that blows extra air through the heat sink. This seems to be working out OK. One problem I had was that the original BB1260 I had was failing and the replacement unit had a much better built-in cooling system for its heat sinks. The original had 3 vents across the top of the unit, the center section sucked air in and blew it out the 2 outside vents. The newer setup sucks air in from the bottom of the unit and discharges out the top, makes for much better air flow.I lost track of your upgrade (so many I have read about). I recall the heat issue. Did you resolve this by moving it? Putting in vents? ... or are you still living with the half power when it reaches over heated condition.
This is how I use my Unity as well, so when I was offered a Sterling BB1230 from another Forum member I was happy to receive it. The Sterling will serve my purposes to charge my Lithionics 315ah Battery as I drive and use it throughout the day, then I will be plugged in at a campground for the night and it can get topped off by my Xantrex 3k inverter. The good thing about the Victron Orion 30a DC-DC charger is that you can hook multiples in parallel to increase the charging amp output. Whereas with other DC-DC chargers you just have to ditch a small one for a larger one, wasting money. I really like Ivuman's choice with the Renogy DCC50s 50a charger and MPPT solar controller. He reported 68a charging from it and the 600w solar (connected to a Victron 100/50 controller) [See post#44 for an operational note].I have a Victron Smart dc/dc 30 amp charger. I agree with what hoosierrun and woundedpig say except that most of my drives between stops are 6 to 12 hours (time constraints generally make my trips 1000-2000 mile circles in 2 weeks) which combined with 400 watts of solar usually allows my FLAs to recover. I'll be switching to 315 amp lithium sometime in February so we'll see if I need to go to plan B.
Other than the fact that you are exceeding the Mercedes extremely conservative (recommended) max draw, I don't envision a problem. The alternator has plenty of reserve, especially if you are not using everything like lights, wiper, AC compressor, defrost grids, and every other possible accessory, many of which is not equipped on an LTV (heated seats, heated steering wheel, rear air, etc.). I don't have any more experience with more than the 200 AH Battleborns, but I ran just like you are doing now for over a year with never a problem. You probably read that my problem was not having the solar to top off the battery. You can't do it by alternator alone. Your system will likely be fine. At one time, I was going to try and upgrade to the 120 amp Sterling. They are expensive and I have mixed (uncertain) feelings, but knowing that 100 amps passes fine, I suspect 120 will too. It is not like that draw on the alternator is going to be for 4 or more hours at over 100. Do you know the wire size and fuse size that LTV has between the batteries? It should be verified that the sizes are of sufficient size.I'm still on the fence on DC-DC chargers. I have two Battleborns, 600 watts solar, and a compressor fridge. I currently just have the Cole relay as a battery combiner. The later works perfectly and is happy pumping 90 amps or more when my batteries are seriously depleted. Extremely reliable, cheap, and easy to swap if it fails. The downside is, if I am stuck idling in a traffic jam it could potentially be hard on the alternator. Hasn't been an issue yet, and many people have 200 AM Lithium with just a relay. (I could mitigate that with a simple on/off switch on the left side of the passenger seat, allowing me to switch it on when I get to the highway.) For me, the 30 amps DC-DC would be woefully inadequate. From the time we park at, say, 4 PM until we take off in the morning we can easily kill 125 AH boondocking with streaming TV, fans, compressor fridge, and misc. Its not that rare to then drive less than an hour to some trailhead or something and park in partial shade. So we need as much charge as possible flowing from the alternator. I'm satisfied with the current setup, but have considered upgrading to a pair of 125 AH Lithionics. That might be a bit much for the alternator to handle bare. I'm leaning towards the Renogy 60 amp DC-DC but would have to make considerable space close to the batteries for it. Or alternatively I may just install the cutoff switch on the cole relay and see what happens with 250 AH and the Mercedes alternator. It might be just fine if I avoid the scenario of an extended idle with depleted batteries.
Thanks thats what I was thinking - that the 220 amp alternator is not going to burn up outputting 100 amps. 99% of the time my solar tops off the battery so the lack of a full alternator charge isn't important to me..Other than the fact that you are exceeding the Mercedes extremely conservative (recommended) max draw, I don't envision a problem. The alternator has plenty of reserve, especially if you are not using everything like lights, wiper, AC compressor, defrost grids, and every other possible accessory, many of which is not equipped on an LTV (heated seats, heated steering wheel, rear air, etc.). I don't have any more experience with more than the 200 AH Battleborns, but I ran just like you are doing now for over a year with never a problem. You probably read that my problem was not having the solar to top off the battery. You can't do it by alternator alone. Your system will likely be fine. At one time, I was going to try and upgrade to the 120 amp Sterling. They are expensive and I have mixed (uncertain) feelings, but knowing that 100 amps passes fine, I suspect 120 will too. It is not like that draw on the alternator is going to be for 4 or more hours at over 100. Do you know the wire size and fuse size that LTV has between the batteries? It should be verified that the sizes are of sufficient size.
Bear in mind, the ideal charge rate for LI is 0.3C, or 60A for your 200aH bank.Thanks thats what I was thinking - that the 220 amp alternator is not going to burn up outputting 100 amps. 99% of the time my solar tops off the battery so the lack of a full alternator charge isn't important to me..
I do have some reservations about going to 250 AH, but possibly not enough to dissuade me from trying.
I think I have a 150 amp ANL fuse to the battery from the relay. I didn't check the wire size, but I assume its adequate for the fuse rating.
I am starting to think that just adding an on-off switch to the relay would be a nice addition for the situation I currently worry about - extended traffic idling with a near depleted battery. Obviously for 630 AH you need a DC-DC charger, or probably even 315.
I was going by this quote from Battleborn on their FAQ page:Bear in mind, the ideal charge rate for LI is 0.3C, or 60A for your 200aH bank.
I know I recently posted this, but I added the switch you are referring to. I put it on the blue ignition signal wire going to the Battleborn Lithium Isolator (the first of which was defective). I have heard that some have put the switch on the ground wire. It is an LED DC switch. I make the decision about whether to enable alternator charging when we break camp, before the engine is started. If the batteries (300 AH BB) are quite depleted, I know they can pull 100 amps on alternator charging. In this scenario, I let my 600 watts of solar do the work, slower, but with more control.I am starting to think that just adding an on-off switch to the relay would be a nice addition for the situation I currently worry about - extended traffic idling with a near depleted battery. Obviously for 630 AH you need a DC-DC charger, or probably even 315.
I only read these forums part time so I probably missed that (or I have been known to forget lol) but that's exactly what I've decided to do. I ordered a sprinter lighted toggle switch I can put in the dash and will try doing the same thing.I know I recently posted this, but I added the switch you are referring to. I put it on the blue ignition signal wire going to the Battleborn Lithium Isolator (the first of which was defective). I have heard that some have put the switch on the ground wire. It is an LED DC switch. I make the decision about whether to enable alternator charging when we break camp, before the engine is started. If the batteries (300 AH BB) are quite depleted, I know they can pull 100 amps on alternator charging. In this scenario, I let my 600 watts of solar do the work, slower, but with more control.
As part of this 630ah Lithionics upgrade, I chose the Renogy 50A DC-DC charger to regulate the max charging of the house batteries from the alternator. I installed it in the step compartment (see pic #47 on page one) and have been pleased with it so far. I verified the charge rate directly from my Lithionics battery Bluetooth app while driving. After letting the batteries discharge below 50% to test the alternator charging, I observed the charge rate at 64 amps within a few minutes after starting my 1-hour drive back home from boondocking in the desert for a couple of days. It stayed at approximately the same charge rate for the entire drive. The refrigerator was off for the test but my original 600w solar array was still on. I was averaging about 15-20 amps from solar just before I started home so that was obviously supplementing the alternator charging. Here's the glitch; if you are utilizing the built-in MPPT solar controller as I am to charge the starter battery while in storage, the solar breaker to the Renogy solar panel (1, 50w panel in my case) must be switched off while driving or the max charge from the alternator will be limited to 25 amps. That's is a pretty weird design in my opinion but no biggie to switch it off while driving. I just open the step compartment and flip the breaker then switch it back on when I park.In my opinion, everything looks good except the Sterling 30 amp chassis to house DC to DC charger. You will be disappointed. The actual output is 23 to 24 amps and any other significant draw takes away from battery charging. I recall reading where people with the newest LTV's (with the 30 amp Sterling), were only seeing 9 to 10 amps going into the battery after the 12 volt Dometic Fridge was drawing its 13 to 14 amps.