Xantrex Truecharge2 Reliability?

[jseyfert3]

Hello all,

New member here with a 2015 Rockwood 2306 that we picked up June of 2018. We're upgrading from the terrible group 24 battery to a set of two Trojan T-105 batteries. I'm looking for a suitable charger for them. As I understand, this means take to 14.4 volts (bulk), hold at 14.4 V until the current drops to small percent of capacity (absorption). At this point the battery is full, and you either switch to float at 13.5 V or stop charging entirely. Equalization is done roughly monthly for a couple of hours at 16 volts. Ideally, all stages of charging are temperature compensated as well.

Basically, the only one I've found so far that actually does a proper temp compensated charge, with a proper equalization, is the Xantrex TrueCharge2. This will charge at full current to 14.4 volts, then hold until current drops to 5% of charger rating, then to go float, if desired, at 13.5 volts. Also has equalization mode at 16 volts. Has temp equalization with battery temp sensor, or three settings via button if not.

I've read some things concerning reliability of the TrueCharge2. Anyone familiar with any reliability concerns on it? Any other temp compensated chargers that do a proper charge profile I should consider?

[jseyfert3]

Not a garage, but soon we'll be storing it in an unheated barn. So while cold, there won't be snow or wind, and I could get a propane radiant heater for outside work and electric space heater for inside work.

[MEXICOWANDERER]

"winter should be a good time to work on that".

Do you have a garage? Full absolute shade in Feb is demanded here. I would love to find a manageable free-standing umbrella. for me, not the work.

But I tolerate hot a lot better than cold.

[jseyfert3]

I wanted to close the loop on this as I hate reading threads without endings. Soon afterwards, we decided we'd buy a house and things got busy. Between that and then COVID, we got out just one time this year and the batteries sat without getting hooked up or equalized, though I didw watch the voltage and charge a few times.

We finally left on an 8 night trip. Before we left I did two partial cycles (one around 20 Ah, one almost 50), and fully charged before leaving, checked all SGs (1.275-1.285), and topped up water.

Three nights in the batteries where somewhere around 50% based on voltage measurement about 15 minutes of no load. Load the prior night was the fridge gas solenoid, phone charging, and some background sleeping noise over the camper speakers. Heater probably only ran once or twice all night.

I decided to top off with the generator and set the PowerMax 60 to 15.3 volts unloaded (48 °F right now), hooked it up and the batteries sank all 60 amps since it was voltage limited.

Still have not upgraded any camper wiring yet, I have some 4 AWG connecting the batteries and also going to a battery connector I can tuck in the battery compartment. To charge with the PowerMax I have more 4 AWG from the PowerMax to another battery connector, simply pop the lid, hook up, and plug in. Hopefully I'll get the actual wiring all finished here in a few months, winter should be a good time to work on that.

[BFL13]

The older PowerMax adjustable voltage models with their external knobs on top to work the pot inside, have wires from lid to pot on a circuit board inside. Those wires are very short so it is hard to take the lid off and set it to one side without breaking the wires from their CB connections.

If you do the mod proposed, use long wires from pot to lid knob.

I still warn that you can get in trouble where the pot on its board is connected here and there, so you might miss a connection when trying to swap it out.

[jseyfert3]

I got an OTC hydrometer finally. The first one the float was broke, so Amazon had to send a replacement. I haven't yet checked the batteries, I will do that this weekend.

I decided to go with the PowerMax 60 A converter. I could see it was just a simple 3/4 turn trim pot. I opened it up, which was super easy as they didn't bolt anything to the cover, and upgrading that to a nice multi-turn external pot will be cakewalk, as it's a single sided PCB. Also with the exception of the control board, everything is big beefy through hole components, so if anything breaks it shouldn't be terribly hard to troubleshoot and repair. Which is good, given how upgrading the voltage adjustment pot will void the warranty.z

I'll check and likely equalize my batteries later this weekend, now that I have the converter and hydrometer.

This is probably my last post in this thread, but I just wanted to update for those interested. I'll post under the "DIY Upgrades" forum once I actually get my setup installed in my TT.

Thanks again for all the suggestions and information!

[pianotuna]

Direct from factory lead acid jars need about 25 discharge and recharge cycles to reach full capacity.

[landyacht318]

New( or Uncycled slightly aged) Flooded batteries behave a bit weird in the specific gravity department in my experience. I've had SG refuse to climb on new uncycled GC batteries. I had to drain and recharge them before it rose to acceptable level, and now 3 years later and much abuse later the owner reports no issues and my hydrometer revealed only ~1 hour of 16.2v after a few hours of 14.7v was required to max them out right where I first established them after that initial deep cycle.

It was not just a matter of stratification either, that first weirdness dipping them as i was moving them around, tipping them and also charging them upto 16.2v. The SG refused to get much above 1.260 until I deep cycled them then recharged them fully, then 1.275 on all.

Likewise I could not achieve a full charge rested voltage on my Spanking new NOrthstar AGM until I took ~50% from it and then charged it at 25 amps until full, Then it was 13.06v full charge and stunned
and scared me with the quickness at which it would crank my engine.

I'd say 14.7v them until amperage stops tapering, then drain them to 60% or less, then 14.7v them for as long as it takes until SG no longer rises. If it is still too low then 16.2v. if it still does not respond suspect your hydrometer is reading low.

KNowing maximum specific gravity when new and fully charged is wise, but also record the ambient and battery temperature, and note the interior cell gets warmer than the two outer when charging and the thermometer on hydrometer should register this if you allow enough time for electrolyte heat to move the thermometer level.

I've also seen few new batteries have the same exact level on each cell, so the low cells when topped up later on, will appear to read weaker than teh cell which seemed to be filled highest at the factory. Noting the low cells from the factory can remove a bit of the 'WTF?' readings later, on after watering is required.

As BFL states, as long as it is precise/repeatable and compared to itself in future tests, it can be inaccurate. Its just that initial maxing of specific gravity required to figure out what it the maximum is, and that might or might not require 16.2v, but I would say that it does require at least one discharge cycle on new flooded batteries.

I think Mex once recommended an initial conditioning charge of 14.0v for X amount of hours on flooded GC batteries to 'cure the plates' or some such.

[jseyfert3]

Yes, I know that while recharging the voltage doesn't have anything to do with SOC.

The nice thing about the hobby charger I'm using right now is that it displays the actual charge current and keeps a running total of mAh delivered. Right now, the current is down to about 6.5 A and the total Ah delivered is approximately 50. At 60% SOC I'd expect around 100 Ah will be needed, plus charging losses, minus the reduced capacity new deep cycle batteries have, but it's still probably a good first past indicator of the battery health.

This might be the first time I "roll over" the mAh counter on the hobby charger, since it only has 5 digits. 😄 Typically, I'm charging 2000-3000 mAh lithium battery packs, not massive lead acid batteries.

[BFL13]

Yes, but when recharging the voltage has nothing to do with SOC, so that leaves SG.

With AGMs you don't have SG, but now you do have an ammeter (Trimetric say) to tell when they accept 0.5a/100AH at 14.4 as your marker for full. Not voltage.

But other times you can just use voltage for a general idea of SOC when loads are mostly not running. EG, off-grid your "morning voltage" with the furnace off at the moment, and no lights on, and before solar comes on to jack up the voltage, you can see it is say 12.1 and that means you are at about 50% (Trojans--some others 12.2) so you need a recharge. You don't need an SG reading for that.

Compare your voltage with the AH counter to see if they "match" for approx. SOC. If they don't match, you have a clue to look for why. Such as you left the converter on when on inverter. 😞

Don't believe your battery monitor Percent SOC. Believe the SG. (At home--you don't need to take an hydrometer camping--you never get to true full while camping off-grid so who cares if you stop the gen at 89 or 91 SOC?

[jseyfert3]

I thought voltage was pretty close, but ONLY if the battery has sat disconnected for like 24-48 hours and ONLY if you are using the manufacture's datasheet for that battery to determine SOC.

By "good" I meant floating glass tube bobber type, not that it was $100. As opposed to the 4 ball model (really, how useful is that) or the plastic floating arrow.

[BFL13]

You will have to equalize those batts when you get the PowerMax, to make up for their past neglect.

You do want a glass tube with the bobber in it, but it does not have to be "good one". I use a $10 one, eg. Just avoid those sideways arrow plastic things that are hard to operate to get the right amount of fluid in them and hold them just so and even then they are kind of wonky.

The trick is to use the same hydrometer each time to the same readings. You go with consistency, not accuracy as such. When the SG gets as high as it will go, that's your number (whatever it is) using that hydrometer. That is good enough to tell you what you need to know.

Wait till you do the equalize to get the SG as high as it will go to be your baseline SG. meanwhile just get them as charged up as possible.

With the Wet 6s at least you don't have to achieve a minimum amps charging rate like with AGMs that are down enough to take a Bulk Stage. You can use your 5 amp rate if you want on the 6s and use the time it takes.

Don't use voltage to tell you the batts are full--voltage readings can be very misleading. The SG never lies! Use SG to tell the truth.

[jseyfert3]

Yeah they were both at 6.11 volts, which is just a tad under 60% SOC (6.12 is 60% according to the datasheet). Manufacturing date was January 2019. Got them from a small battery company, clearly they had not been watching/charging them enough. According to Trojan, they should be charged in storage upon dropping to 70% SOC. $300 for the pair before tax, core charge included, so hopefully I didn't get a bad deal.

Right now I'm charging them with my RC hobby charger. Like most chargers, it goes to 14.7 volts, and is not adjustable. 10 A max charge current. It ends the charge at 10% of charge current setpoint. So if I charge at 10 A as I am now, it ends absorption at 1 A. If I set it to 5 A, it would end at 0.5 A and so forth.

I haven't yet bought a hydrometer or a power supply/charger that can do full charge voltage or equalization, so it's just the hobby charger for now. That should get them fairly close to full. After I let it sit a day or two after charging the voltage should tell me, though it won't tell me if I need an equalization. Full charge is 6.37 volts or 1.277 SG (T-105 datasheet).

I will use a hydrometer to check for full charge and the potential need of equalization as soon as I get one. I found one of the good ones today at the local hardware store, the floating tube with a built-in thermometer, but unfortunately the thermometer was clearly broken as it was reading 40 °F in room temp or I'd have bought it. It was the only one with the floating tube scale they had. My guess is battery hydrometers don't exactly fly off the shelves. 😄

[BFL13]

The big thing now with the new batts is to charge them up to true full ASAP, then note their SGs. Say 1.300 or whatever.

(They will be down a little from shelf time)

That is your "baseline SG" to be your target for future recharges. If the SG does not get up to baseline SG, the batts are not full! It takes a lot of time to get to true full, so having them at home gives you that time.

[jseyfert3]

CA Traveler wrote:
NO Don't remove the batteries at home, they are needed for the trailer brakes! Or as the OP suggested use a temporary battery for transport to storage.

That wasn't the OP, since I'm the OP. Someone else suggested removing the batteries, and cautioned to make sure I use a temp battery for transport to storage. I said that if I was going to remove them, I'd do it at the storage lot. Meaning we'd come home from camping, unload, take it to the storage lot, remove the batteries, come home and charge them. So just rearranging the order of things to not need a temp battery.

CA Traveler wrote:
Removing batteries gets old real quick. From the OPs usage I'd suggest a large set of cables from the TV battery to the RV batteries. This will go a long way towards significant battery charge from CG to home to storage.

This is a good idea. I bought the batteries yesterday, and yes, it will certainly get old dragging those to and from the camper. They aren't drastically bigger than a group 24 but they are way heavier!

Anyway, thanks all for the advice. I think I have a pretty good idea of what I'm going to do.