Manual Charging

I posted that Delta 80mm fan to show the upper end of what they can do. You will hear this fan, if it is running at full speed, from a hundred yards away. It also draws 2.3 amps at max speed, which could be amps flowing into the battery instead. The fan controller internal to the Iota might release the magic blue smoke when trying to power a 2.3 amp fan.

I'd pull the fan that came with the Iota, see if it has specs on it, if not plug in the Make and model # and try and find the specs, then find a fan which beats it by 25%, not 200%.

I am very impressed with all of Noctua's offerings, and wish they would design a multispeed 120MM fan in the 140 to 150 max CFM range.

Their one 120mm fan I put on my fridge moves 53 cfm for 0.05 amps. It replaced a 72cfm fan which draws 0.12 amps, and when pushing air against the condenser resistance, decreased fridge duty cycle, made a lot less noise doing so, and taking less than half the current to do so.

High static pressure ratings can be a more significant figure than CFM
as resistance can really knock down a cfm rating fast.

The super High rpm Delta fans are just insane in most applications. For an 80mm fan to move 123 cfm, it is moving air at some serious velocity, and might even physically stress electronic components in the Iota

landyacht318 wrote:

Ridiculously powerful and loud 80mm fan:

http://www.frozencpu.com/products/17269/fan-1083/Delta_80_x_38mm_Extreme_High-Speed_Fan_-_1325_CFM_-_Bare_Wire_PFB0812DHE.html?tl=g36c15s699

This one looks good. Mine is in an outside compartment so not worried about noise so much.

Chemistry, Electricity and Reality do not play well together. They love to start pointing and yelling "Liar! Liar!"

A good quality battery in good condition will not have sandbox shovel and bucket fights. The consistency, and repeatability of charge/discharge SG readings should be impressively equal and stay that way for a long time.

This is why the (excuse me)...

H-Y-D-R-O-M-E-T-E-R (gotta throw out a little bait here)

can act as a polygraph machine.

The battery that has bouts of PMS is not going to live as long as one that consistently smiles at you. Keep using it until it plays possum or you start working for it...

BFL13 wrote:

mena661 wrote:
Side note, I just noticed that 80A only goes to 14V. Might have to get that adjustable Powermax instead. So, I can just let Vabs run till 0 amps with no shot of 15+V at the end to get it topped off?

I use the mod 100 at fixed 14.8 but after that I use the VEC to do any topping off/equalizing.

I imagine that external pot 100 will cost twice what the old PM3-100s cost now, but you have to take the top off the old one and twiddle the tiny blue pot with a tiny screwdriver and not blow anything up. Then put the top back on and leave it be. (or every time you twiddle it you have another chance to break that tiny thing)

If it is true they will limit the external knob 100 to 15.5v then you will still be using the VEC anyway. I tried my external 100 set at 15.5 (highest mine will go) and it acted the same as the VEC pretty much, with amps about 4 starting off and then tapering. So about 4 is the natural acceptance rate for a pair of 6s at 15.5 I guess.

I gather Mex wants one that you can set your 5% worth of amps on it and ease the voltage on up to keep the amps the same as the equalize runs on. Very hands on.

These things I /we have can only do a constant voltage and amps will taper. Still, I have no problem getting the SG to baseline doing that with my 6s and I am nowhere near 5% amps at first and they taper.

OTOH I never did get my old T-1275s equalized. Their cells are all over the place, but the batts are doing great. I just have a baseline for each cell which I keep score on. Oh well.

They are an inconsistent and strange lot, those T-1275s. One of mine, 5 cells will make 1.275 to 1.280, but cell #3 is the Lazy Susan of the lot, and 1.265 is the best I can get out of her, after equalizing to 15.9V at 6 amps. Amps drop off to 3 amps, and I did an equalize a couple of days back with my primitive Sears 6 amp 12V dumb charger. Took about 3 hours after doing a full on top off charge the day before. Got cell #3 up as far as she'll go.

Not too often, but every once in a while, that T-1275 needs to be stuffed full throttle by a dumb charger capable of 16.0V. I seem to do mine when I get back from a trip, and then I do an EQ every time, right before another trip. Despite it's quirkiness, it always works really good after an EQ session, takes like 20 to 30% longer, time wise, to run it down to around 50% SOC. Frankly, I just don't think doing 50 to 80% or 50 to 90% charges daily, really cuts it.

This next trip, I believe I am going to just bring the battery home from the storage yard and zap it with that dumb 6 amp charger overnight, before taking the battery back to the storage yard and the trailer.

Despite all the cycles, I am not losing any water... Not as much sun in Sept in Yellowstone, we'll see how the 120 Watt portable panel does in Fall versus June 21st getting the battery back up to snuff.

Kind of hard finding more info on the Iotas adjustablity. One site says there is a small screw for the pot behind a piece of tape/sticker, no case opening needed, and it brings up both ABSV and float voltages. I'll keep looking.

edit:

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/26613945/srt/pa/pging/1/page/3.cfm

Looks like the fan already blows into the case. For some reason I assumed they sucked air out.
Not sure of the Iota's fan max Cfm rating, but I am pretty sure it is 80mm. I just put one of these exhausting my electrical cabinet. Used a provided resistor cable to slow it down and it draws 0.07a

But it not a particularly high speed 80MM fan

http://www.noctua.at/main.php?show=productview&products_id=9&lng=en

Super powerful 80MM fan I have one of these on a gooseneck and a speed controller for internal air movement:

http://www.newegg.com/Product/Product.aspx?Item=N82E16811999612

Ridiculously powerful and loud 80mm fan:

http://www.frozencpu.com/products/17269/fan-1083/Delta_80_x_38mm_Extreme_High-Speed_Fan_-_1325_CFM_-_Bare_Wire_PFB0812DHE.html?tl=g36c15s699

BFL13 wrote:

mena661 wrote:

KJINTF wrote:

Sorry to hear your Iota is dying

This one came with the rig. I have no idea what shape it was in when I got it. It started doing this from the get go. It still works, just not when it's 100+. I'll be keeping this one, thanks though.

BFL13 wrote:

If it is true they will limit the external knob 100 to 15.5v then you will still be using the VEC anyway.

Mine are a lot easier to get to 100% than yours. All they need is low to mid 15V. Not much time at that either. What I've noticed with the MW is that because it has more amps than my HF manual charger, it takes less time for EQ's and top offs. Pretty sure I'll be able to do it all with the Powermax. I had emailed Randy about the adjustable voltage PM and it was in the mid $200 range.

Here is the one I have that I did the mod to. No sense getting a fancy PM4 if you are going to do the mod I did on it. I have doubts about the specs they give the PM3 here, sounds more like a PM4 but anyway, doesn't matter for the mod application.

http://www.boatandrvaccessories.com/powermax-pm3-100-100-amp-converter-charger1.html

No warranty on the PM3 though. Phased out

BFL13 wrote:

I adjusted the voltage to 14.8 with the tiny pot, put the lid back on and installed the unit where I can hardly get at it. I just reach in and grab its 120v plug and plug that into an extension cord from the gen. I could not use the external pot one where I have the mod 100, Would not see it or be able to reach the knob.

Nothing but the best here bud! Yeah, I remember your electrical theory as it pertains to part-time RVing in the Yukon thread. :) And here I thought I had too many chargers. LOL! You need to join the rest of us and get yourself a MeanWell! One can't have too many pots to adjust.

landyacht318 wrote:
Apparently the Iota can be opened up and has a Voltage Pot too.

Heard about that adjustable pot in the Iota too. Can't remember where though. Funny you mention changing the fan out. I was thinking about just that earlier this evening. And my Iota has an external IQ4 module. I thought they all had external IQ4's.

Apparently the Iota can be opened up and has a Voltage Pot too. Not sure of all the details but apparently it has to be a model without the internal IQ4 thingamagiggywhosyseewhattseeyymabobber 'wizard' like device. Hope thats not too technical.

I think Mena's 105f limited Iota needs to have a new higher CFM high static pressure rating 80MM Fan turned around pushing air inside, and the Pot cranked upto 15 for effective bulk charging.

How hard can it be to solder on a new Pot to mount externally?

I want to do this with a MeanWell 30 amp power supply. Anybody know the range of the tiny fragile circuit board mounted potentiometer?

mena661 wrote:

BFL13 wrote:

Here is the one I have that I did the mod to.

Thanks BFL but where I have the present converter and MW mounted, tweaking a pot inside the unit will not be possible. No head room. Turning a knob on the outside of the unit is much easier. If I had bought the Iota, I'd try to make your way work but since I didn't...no big deal getting the adjustable one.

.

I adjusted the voltage to 14.8 with the tiny pot, put the lid back on and installed the unit where I can hardly get at it. I just reach in and grab its 120v plug and plug that into an extension cord from the gen. I could not use the external pot one where I have the mod 100, Would not see it or be able to reach the knob.

Meanwhile, since that (repaired) mod-100 is now working so well, I have little use for the external pot 100 one, which sits around doing nothing. I already have a converter for floating at 13.8 (ok for winter here)

I could toss the perfectly good 7355 and the mod 100 and my VEC, and just use the external 100 in a place mounted where I can get at it, but don't need to.

Only got into this when the mod 100 blew its thermistor and I couldn't fix it, so they sent me the prototype external one to try out and report back on.

Then that blew its thermistor too. Then I learned how to repair the thermistor (see that long thread from last winter) and got both working again. Now I have two 100s which was not the plan. I can't run both because the Honda 3000 can't handle two. Anyway, it's all too complicated.

Fact is if starting from scratch, the adjustable 100 would be great as an all-singing , all-dancing charger/converter.

Mena still has the Iota like I have the 7355, he has a VEC. So to be as good as me, all he needs is the cheapo 100 from boatandrv, modify it without breaking anything, and good to go! :)

Or he can spend more money and try for a higher station in life! :)

BFL13 wrote:

Here is the one I have that I did the mod to.

Thanks BFL but where I have the present converter and MW mounted, tweaking a pot inside the unit will not be possible. No head room. Turning a knob on the outside of the unit is much easier. If I had bought the Iota, I'd try to make your way work but since I didn't...no big deal getting the adjustable one.

MEXICOWANDERER wrote:
Buy a pair of the 40 amp MW. and I'll work with you step by step to make a blow up resistant two stage converter. One runs on a timer, and is set to 14.8 volts the second MW is set to 13.6 volts and is the default maintainer.

Thank you MEX but DW won't let me get another MW. She considers my present one a temporary fix.