Problems with Boondocker 60 amp converter

Having gone to a industrial grade 8 year warranty 150 amp hour Telecom surplus AGM battery that takes only 21 amps when charging, has an acid surplus, and has very thick lead plates, at 105 lbs of weight for 150 ah, you would be correct in saying I no longer need to float charge. Reason being that AGM batteries have aa very low monthly loss of charge, compared to FLA batteries.

My procedure now is to set the voltage to 14.40 V on the Meanwell, and watch the amps come down to 0.75 amp charge rate... a 0.5% rating of the battery ah capacity, and shut things down, as well as disconnect everything. I should think that 3 months of storage is fine in the winter time, I will apply a recharge the 1st of the month in the warmer 4 or 5 months here in So Cal, to stay on top of maintenance charge. If I get 8 to 10 years out of the battery, I'll consider the AGM money as money well spent. I consider the money spent buying the Mega Watt, the inline RC watt meter as something that will outlast me. If I have it go bad on me, oh well, better $55 than $155. It does exactly what I ask of it, nothing more, nothing less, no surprises.

If I get the meanwell do I need to purchase one these pots?

LY & Niner

tks for both replies.

have ordered a 1k to use, and a 2k to get the dial (sigh). i'm comfortable desoldering/soldering and will take pics of the project when all the parts arrive. also have the megawatt 400 and one of the inline meters on order (from other posts).

if all works out, i hope to mount the mechanism in our travel trailer storage area with output leads to the batteries (permanently connected with 10 awg wire and ring terminals with suitable fuse and cut off switch) where i can drive it with the honda 2000 when required by simply opening the access door and plugging the mechanism into the generator and setting the timer (and yes, starting the generator for the pedantic readers)

will investigate the finishing solar charger once this bulk charger is working.

great work on all of you ( and the others ... mex, etc.) for the information and pioneering experimentation.

keith

I use the full voltage range of my Meanwell rsp-500-15( well, below 16v anyway), and with the original trim pot this range was from 13.23 to 19.23v.

With the original 1K ohm pot in both the cheapowatt and the MeanWell, 0 ohm resistance on the pot, the PS goes to its maximum voltage, maximum resistance and the PS goes to its lowest voltage.

The Cheapowatt and Meanwell came with a 1000 ohm pot. I measured the original trim MW pot upto 970 ohms( going by memory here)
The 10 turn pot measured 995ohm( again memory)

With the new pot wired in with its ~20 more ohms of resistance, minimum voltage dropped to 13.12v, down from 13.23v.

So I assume if I were to use a 500 ohm pot on my Meanwell, I would lose the lower ranges of voltages, which would not be desirable for me as I use mine to float my battery once full.

I am not sure the original voltage range on the Megawatt, I thought 15.5v was their maximum, and Niner has no use for the Megawatt to float his battery at a lower voltage, and perhaps never noticed that the voltage does not go as low as it did with the original 1000 ohm potentiometer. And the markings shown in photos on the pot of the MW indicate it is a 1K ohm potentiometer.

The 10 turn pot I used on my Cheapowatt and then the Meanwell is this type:
http://www.amazon.com/WXD3-13-Shaft-Turn-Wound-Potentiometer/dp/B00R1LTWFK/ref=sr_1_7?ie=UTF8&qid=1454543081&sr=8-7&keywords=10+turn+1K+ohm+potentiometer

It is not very high quality as it developed uneven spots Which some DeOxit F5 fader lube resolved. But the spots came back and a second application resolved them again, but once again they are slowly returning, but it is easy enough to loosen the 3 screws pull it apart enough to get the red squirter hose in there and reapply.

These uneven spots cause my Meanwell to click on and off when adjusting voltage.

I recently got a 2K ohm pot for another project, that has the same appearance of the Pot niner shows. It is heavier than I expected. The turns counter feature is awesome and it has a brake on it too. I checked it through its 3600 degree range with my DMM and it was smooth and steady the whole way. I'd have to recommend this type over the type in the link above though I know not how it will last after a few dozen cycles. I ordered mine through Ebay for under 5$. It took 9 weeks to arrive, I was about to give up on its arrival.

If one has the confidence and skills to solder in their own wires for an external 3600 degree potentiometer, get some thermal grease to reapply between the transistors and the casing.

a 500 ohm range of adjustment over 10 turns would certainly allow more precision when adjusting voltage, but it is quite easy to dial it into 0.01 a volt with a 1K ohm potentiometer at half the sensitivity.

I would NOT use a 2K ohm pot to replace a 1K ohm pot. I imagine the magic blue smoke could escape.

The Powermax adjustable voltage model's potentiometer's range is less than 360 degrees. It is very touchy to dial it in to 0.01 of a volt, practically impossible, but someone seeking 40+ amps in a manual Adjustable voltage premade package, should consider one of these instead of trying to convert a MW power supply to an external potentiometer.

windviewer wrote:

NinerBikes wrote:
3590S-2-501L-500-Ohm-BOURNS-Rotary-Wirewound-Precision-Potentiometer-Pot-10-Turn-

Great, thks for the link

Is there any difference in using this 500 Ohm versus the 1K Ohm versus the 2K Ohm variants? From reading all the threads I see all three potentiometers used at various times (albeit on different PSU's).

You guys seemed to be having a good time building these things :)

Sensitivity to settings. The 500 ohm is most sensitive, range wise, making it easy to maintain voltage either way of the locked setting. The 1000 ohm is a little touchy, the 2000 ohm even more touchy, to having to be exactly on the mark to get the regulated voltage you want. Turned all the way up, the Megawatt will deliver 15.56V, turned all the way down, I think it got down to around 11.5 or 11.6V, useful if used as a power source for a 75 watt Ham radio like my Kenwood 2 meter unit, just set it at 12V and call it good, and don't burn up any parts on the radio being overdriven.

What I can say is that the 500 ohm unit works fine and keeps my 30 amp MegaWatt in complete regulation, at both ends of adjustment. Verified and measured by SCVjeff with a Fluke Digital multimeter, when placed under load.

You do need to know what you are doing, wire wise, heat sink wise, and solder wise, pulling the old pot off a circuit board, and resoldering in the new wire. Someone wise with Ham radio's at your local Ham radio club and modding them probably has all the right equipment to do such type of work on electronic circuit boards, and do it right the first time. If need be, pay them for their services. Add a RC watt meter in line for recharging batteries, it's a valuable addition to knowing exactly what is going on with your batteries while recharging, once you gain some experience with it. Some might call it geeky, I consider it a necessity, knowing how many amps the battery is taking while recharging, and voltage also, as well as cumulative amps recharged.

NinerBikes wrote:
3590S-2-501L-500-Ohm-BOURNS-Rotary-Wirewound-Precision-Potentiometer-Pot-10-Turn-

Great, thks for the link

Is there any difference in using this 500 Ohm versus the 1K Ohm versus the 2K Ohm variants? From reading all the threads I see all three potentiometers used at various times (albeit on different PSU's).

You guys seemed to be having a good time building these things :)

duplicate post deleted.

RJsfishin wrote:
Yes, ignore my posts, while at the same time remembering the fact that everything I say is true,....except the few post that really were made made to agitate a little.
It has always been said "you can't fix stupid", and the last few posts prove that to be fact for sure.
I am glad that there are a couple here that really do know what they are talking about,....(not including mex, niner, and yaht) I respect them, and I do still learn from them.
It seems that there is a growing number of battery fryers, that they could form a "Battery Fryers Club" of their own. That seems to be their whole life anyway, mite as well form a club and get some real recognition. But on 2nd thought, where would I then come every morning for my comedy of the day.:(
:)

Where you make your mistake is in believing the battery charger manufacturers specifications. They don't warranty batteries.

Ask the battery companies what their batteries need to fully charge, and you'll get the real specifications. 14.8V for most Trojans, US batteries need 15.3 Volts to fully charge. Take your pick as to who you want to call a liar. The ones who warranty charge controllers, or the ones who warranty your battery. Maybe it's beneficial for both of them to screw you and keep you in the dark on the truth?

No one here in this thread has commented ever about "roasting their battery".

What they have commented on is getting 500 or more deep cycle recharges out of their battery using proper recharging methods, techniques, etc, and the one method that comes up consistently is that they all recharge and set the voltage manually to get all those recharge cycles. They all do thorough equalization charges when necessary. What they don't use are charge controllers that offer nothing but promises or multiple stages of charging that are "set it and forget it". This is because in day in and day out dry camping use, the set it and forget it crowd ends up losing battery capacity in short order, within a week or two, of using the fancy 3 or 4 stage chargers, most of which are or were designed to be pedestal queens, tethered to a pedestal, day in and day out, not to a generator for an hour or two a day in the morning and evening.

Two things I know for sure... my WFCO 8955 smart charge controller is dumb, and my Walmart Deep cycle battery was useless to me in less than a year, using the WFCO.

Another two things I know for sure is the well used Trojan T-1275 that was left for dead at the golf course, I got another 2 years of life out of it for free. How? I top charged it at 14.8v. Then I had to equalize charge it to 16.0V, three times, before the Specific gravity was where it was supposed to be on all 6 cells.

I bought and sold a PD 9245 with wizard pendant, it didn't do the job, 14.4V was not enough.

I bought a MegaWatt 30 amp PSU and a RC watt meter and started charging at 14.8V. Lo and behold, that worked for me to bulk charge.

I bought a 150w poly solar panel and an adjustable voltage charge controller. Not only did it top charge, but I could equalize charge with it also, set at 16.0V for an hour or two in the early afternoon, if needed.

Two more years out of a free golf cart industrial grade battery, left for dead, properly recharged at the correct voltage.

So yes, some batteries can be resurrected from the grave for a bit... the the true deep cycle brands that have been mistreated by 3 or 4 stage charge controllers for a bit of their life, before finally being treated and recharged right and correctly. Not the Walmart stuff or car jar shaped and "GROUP 24,27, 29, 31" labeled garden variety batteries sold at most retail outlets.

I get my industrial grade and strength batteries at specialty shops nowadays. With good reason. Far better longevity and value per dollar spent, per year of life. My TT never sees a power pedestal.

YMMV, I no longer waste my time or money trying to make silk purses out of sows ears.

As for your wire gauge recommendations... someone is going to burn something down following your recommendations, sooner or later. There's cutting corners, and then there's gross negligence. Your wire recommendations fall under the second category for people that have no business wiring anything, without understanding the theory and load calculations behind what they are doing.

I'd hate to be in a car, an airplane or a space ship wired by you.

landyacht318 wrote:

I also added a 10 turn potentiometer, replacing the tiny one on the circuit board which required a jewelers screwdriver and a fine tough to adjust voltage. The Tiny potentiometers are rated for only 100 cycles through their range,IIrc and I would have quickly wore one out.

Any part number recommendations/sources for this to go with a MegaWatt S-400-12?

TKS, Keith