-
replace Vanner with Victron?
Okay, so talk me out of this.
As discussed in this thread, I have two Vanner Battery Equalizers that are wired in parallel. Per the Vanner manual, you can configure them to balance two 12V batteries that are wired in series, or you can use the 12V output to charge a separate (house) bank of batteries. As you can see in the drawings below, mine are really only serving as 24 VDC to 12 VDC converters. And they’re both broken, putting 24 volts to the 12 volt outputs.
These Vanners feed into a Vanner 50-140 Battery Isolator. It’s broken, too. The alternator voltage (center lug) is not reaching the two house battery banks.
Being the cheap SOB I am, I started exploring alternatives to the 100 amp Vanner, which runs about $700 or more. Victron has 70 amp converters that take 24 VDC and turn it into 12 VDC, which is all my Vanners were doing. The Victrons run about $140 each, and I would use two. They also have a smaller footprint, so two will fit into the space of the one Vanner 100 amp unit. Since I am replacing two Vanners, I free up space either way.
The battery isolators from Vanner and Victron are similar in price, but the Victron uses FETs to achieve a voltage drop of about 0.02V. They claim that the diodes in other units will drop about 0.3V, although I didn’t see those numbers from Vanner. Any way, they are similar in function, size, and price.
I drew my current setup alongside my proposed setup. Links to the Victron stuff are below. What am I missing?
Victron 24/12-70 DC to DC Converter
Victron 200-2 Battery Isolator
1984 96" with 8V92TA
(remodeled Liberty Coach)
Greenwood, MO -
21 Replies
-
Chad, others are going to be able to provide more detail but one prominent converter had a recall because of equalizer issues. They were non-Vanner and I believe some coaches had serious expensive damage due to inverters.
Anything can fail, but in my 29 years of Prevost ownership and hanging around with Prevost owners I am unaware of any Vanner equalizer exhibiting the serious issues of the non-Vanner replacements.
Tom might have a better memory regarding this than I do.
-
I chased every last wire today that was feeding off of the Vanner 12V posts, and thus receiving 24V instead. It turns out that only the battery isolator and the 4-pin trailer wiring were connected to it. Since the Vanner isolator isn’t passing the alternator voltage to the house circuits, and I have never towed anything, I appear to have dodged a bullet on those bad Vanner battery equalizers. Having both put 24V out on their 12V posts seems like a heck of a coincidence, and is a head-scratcher.
Interestingly, my 12V loads in the cockpit appear to draw off of a house circuit, so I’m becoming convinced that my Victron setup is feasible as long as reliability isn’t a problem. I hope someone will chime in if they have concerns about the Victron equipment.
-
The only Equalizers with a recall that I remember is Sure Power and I had to change out one of those on my last Marathon. They were recalled for a fire hazard.
Victron is good stuff from what I read and as long as the function is merely a converter, I don’t see any downside. I’m not an EE, so this is just an opinion.
-
If I recall the Vanner is an isolated supply but I can see from the Victron data sheet it’s an unisolated buck converter. There are two main issues to consider between an isolated and unisolated converter.
In an isolated converter there is a transformer between input and output. If something fails in side it usually blows a fuse and the output goes to zero or the input opens and the output goes to zero.
In a buck converter there is a FET switch between the input and the output. The duration that that FET switch is on controls output voltage. A common failure mode is that the FET shorts. This connects the input and output together. There are ways to deal with this as an example by putting a crowbar circuit across the put that shorts it if the output voltage goes to high, but it’s often not done.
The second issue is that isolated converter are by their nature less noisey then unisolated converters. This may or may not be an issue.
-
Check Ebay. I have bought Vanner units on Ebay very reasonable
-
Thanks for your replies, guys. Dick, I’m particularly interested in your description of the isolated versus non-isolated converters. I can’t wait to crack open the Vanners and figure out how they managed to fail with 24 volts on the 12 volt posts. I’m off to American Fleet tomorrow for some engine work, so I’ll post an update when I move forward with this project.
-
I thought I’d provide an update on this project. It’s a little premature since I haven’t done any serious testing, but other projects will keep me from doing that for awhile.
I made the change to Victron equipment, exactly as I outlined above. Everything seems to be working okay so far. Time will tell if heat is an issue for these units. The DC/DC converters have small internal fans, but I don’t really know what kind of air temperatures they’ll see. I used mostly 1/0 cable, which is likely overkill. Most of my old positive cables had badly deteriorating sheaths after 35 years, so I want to minimize heat where I can.
The new circuit breaker replaces a Klixon breaker that was pretty well hidden, and therefore didn’t make it into my earlier drawings. Moving it above the solenoid helped minimize my cable lengths.
The “while you’re in there” on this project went to new levels. I rebuilt the chassis and house battery trays, including new slides. I also rebuilt the house cut-off switch assembly. I’m particularly happy with the way that turned out. I even refreshed the intake “Y” ducting since I had it out for better access. Reinstalling that was a bear. Comments and criticisms are appreciated.
edited for spelling
-
Nice job Chad. Assuming your Victrons are in the engine compartment, do you have concerns regarding heat likely in excess of 200 degree’s?
1984 96" with 8V92TA
(remodeled Liberty Coach)
Greenwood, MO -
Chad, I agree with Tom about heat.
Way back when Interstate was considering the manufacture of Gel Cell batteries I was given the opportunity to install them and test them on our first coach. They were for the house and at the time Liberty stacked the house batteries in the engine compartment over the chassis batteries.
After some failed batteries we started measuring temps in that area which would be just about a foot away from the bulkhead your Victron devices are mounted on. The temps were as high as 185 degrees.
I would contact Victron and see what their engineers suggest. You cannot lower the temps in that area because the air flow is mostly from the radiator fan pulling heated air and blowing it across the engine which has the heat of the engine, including exhaust manifolds and turbo intake tubes which can get to and exceed 1000 degrees.
It will involve a lot of cable, but can you relocate them to under the bed with a small fan pulling room temperature air from the bedroom floor?
-
I do have concerns about the heat, but decided to give it a try. Victron provides de-rating data for various temperatures. The two 70-amp converters are oversized, so I think it may work out okay. At 200 degrees, I would be well above the maximum temperature for the converters though. That’s hotter than I am expecting, because nothing up there has been uncomfortable to the touch after shutdown in the past. I suppose I’m betting on somewhat lower temperatures, but at least I’m betting with money I can afford to lose. If all three Victron devices die, I’m only out about half the cost of a Vanner. Buy them all again to install in the bedroom, and it becomes a wash.
You’ve already identified my plan B, which is to move things into the bedroom. I really wanted to put these in the curb side hanging closet that is directly above their current position. The only way I see to run cabling there without some interior modifications would be to drill through the air box. That seems like a bad idea. Tell me it’s not and I may turn that into an electrical bay, including lithium batteries at some point in the future. The closet is awkward to access, so mostly stays empty.
Due to a couple of toe kick heaters, I don’t have much free space under the bed. I do have three drawers that are a pain to use, so maybe I could re-purpose the one closest to that closet. Wiring that would be simple. Removing the drawer to get at the heater below it in the future would be a real pain though.
-
Our north-south bed in our first coach had two toe space heaters and two drawers under the foot of the bed. But the engine cover was in a wide open spot.. Going by memory I am thinking I could have located the house batteries in there if they were gel or AGM or LiPoFe4 and replaced the drawers or maybe one of them with a vented panel with some type of forced air fan ducting triggered by a thermostat.
There was almost nothing I needed to remove the engine cover for, including the alternator which I could remove from beneath the coach, by dropping it down to the bell housing and then manhandling it from there.
I cannot remember if I could do the same with the compressor or power steering pump.
1984 96" with 8V92TA
(remodeled Liberty Coach)
Greenwood, MO -
Mine is similar, Jon, but the difference is key. I have one toe kick heater on each side of the bed, each with a drawer directly above it. I have just one drawer at the foot of the bed. I could sacrifice that drawer, but the cable runs would be pretty long. My Espar heater is INOP, and I don’t know if I’ll ever bring it back online. That makes me very reluctant to mess with the electric heaters. I do think the nearest side drawer would be an acceptable option though.
I think I’ll run a couple of hours at fast idle today and shoot temps with an IR gun. If that goes well, I may do a few hours on the road this week and shoot them again. It’ll be a nice break from projects. I’ll follow up either way.
-
After a road run you are going to get the heat. One alternative is id you can enclose the devices and use a small fan to pull or push fresh air around them.
I’m curious about what temps you get at the devices. I measured the temps at the engine end of the batteries and the battery failures were apparently thermal runaway because as temps went up the voltage is supposed to go down, but back then the alternator regulator was the old big cast aluminum regulator that was supplied with the gear driven 50DN.
-
Chad: Put a remote thermometer on the new devices and put the readout on the dash so you can monitor the temps. Watch the temps change while you’re driving and then again when you stop with the Detroit idling. Hopefully you won’t get surprised.
-
The air temps will go up and down, but the devices Chad has, as well as other items in the engine area have enough mass so they will not make rapid temperature changes, up or down.
Log in to reply.