Re: HCH1 DIY IMA Reconditioning
 

that connector image is wrong. The one I have is 6 pins on the top and 8 on the bottom, one of 8 is unused.

Re: HCH1 DIY IMA Reconditioning
 

you have the right one earlier... I had wrong one.

using yours I still had an issue, pin 11 is unused.
5 to 6 was near 0 also

EDIT: I think I wrote it down wrong, you never said pin11

ended the day drawing 540mA at 136V
pickup again in 8. Continue draining or begin charging? By the math I should have pulled the full recommended amperage out before shut down tonight.

Re: HCH1 DIY IMA Reconditioning
 

No reason to expect you'll get HA results since you're not doing the HA process. This has been much more conservative due to the fact that it didn't get a full charge.

The fact that it's held this voltage for this long is a good sign you are consuming a lot of voltage depressed capacity.

Continue to 120V unless you have a time constraint. Consider putting it on charge overnight.

Whatever the case, do not leave it sitting in this discharged state. Hit it with the charger for at least 20-30 minutes. Voltage should climb rapidly provided the PSU doesn't lag because you're below its minimum voltage.

Re: HCH1 DIY IMA Reconditioning
 

I didn't see this before I zonked out for the night, on the upside, or dpwnside... the pack recovered to 150V overnight... guess it's got alot hidden in there.

charging it now.

did find some concerns on the voltage taps though.
all at 14.5-6. Except one at 13.5 and (I'm hoping I just had poor contact) one at 8.7

Re: HCH1 DIY IMA Reconditioning
 

You need to keep track of the taps, i.e., record them and their position, so you can refer back to them. You want to keep an eye on those two. If that was done near 144V under load, those two low ones are an issue.

Re: HCH1 DIY IMA Reconditioning
 

It was under load and all were done around 135V.
when I woke up and began charge it was at 150V, at 160 now 2 hours later.
Seems like picking up just under 1V per 10 min is normal for this pack at this time.

This next charge is going to take all day isn't it?
I'll go see if I can find some 150watt bulbs... or should I go higher?
Looks like the depot has 300's http://www.homedepot.com/p/GE-300-Wa...-TP6/202217522

hmm 266 watts at 120v with a lifespan of 1950 hours 6000 lumens
300 watts at 130v with a lifespan of 700hrs
??? watts at 170V with a lifespan of 700 (minutes)? HA!!

two of those might look like Jesus coming back!

Re: HCH1 DIY IMA Reconditioning
 

24 hour charge if you can. If you can't, and you need to install before you can do a full charge/discharge, you should just charge for 4+ hours and install - use the car to charge the pack at 2500rpm until it's full. Reset 12V and repeat 2 more times.

The next time you hit that voltage on a discharge under the same load, repeat the measurement. If you're getting any benefit, those two with low voltages will be higher then the first measurement - possibly even higher than the others.

If you want to expedite, 2X 300W would like like a single 150W - which would be respectable.

If you switch to bulbs, you'll need to adjust your capacity calculation:

Discharge with the 300W to 144V, record end current/time, terminate discharge and do the calculation.

Swap out to the lower watt bulbs you were using and repeat the discharge to 144V - repeat the calculation as before. It's not going to be a lot, but it's good to have apples to apples.

On the higher watt bulbs, you MUST check the pack frequently if you intend to capture the correct voltage. It can move through it very fast.

Re: HCH1 DIY IMA Reconditioning
 

I was curious to see yesterday vs today, recorded the volts, 164.6. And then looked to see how long it took to hit that yesterday.

whomp whomp....I started at 166v

you said measure volts between pin 5 and 4 on the orange F. Connector right?
Nvm it's good.

both last night and today, 136v and 164v. I'm getting .1 to .2v. Wouldn't that mean I have TWO dead sticks which are also next to each other?

I know non loaded voltage doesn't tell near as much as voltage under load, but the two other measurements of concern are decent right now,

3 legit problem children, 13 -5, 7 -2, and 8-3
The first and last now look good the middle still lagging a little. But it's still filling.

question:
It seems like you feel more benefit can be had from overcharging that from deep discharging.
First, Am I reading that correctly?
second, can you explain why we want much more to push up than to push down?

I had a nicad dust buster which NEEDED to be 100% dead before charging to get any meaningful benefit from charging... I know nimh are not the same but I guess that's where my presupposition to want to drain more than charge originates.

as for the planned course of action at this point,
I can leave it charging for about 21 hours.
problem is after that I will be our of the house for about 8 hours. Yesterday's drain to 144 took 5ish.. the only way I see around it is to plunk the dual 60s in, drain at 30 instead of 45, at a glance that should boost the drain time by a third or maybe a little more, then I can rush back and measure.. hopefully it's around 144 at that point (assuming some small gains also)

Re: HCH1 DIY IMA Reconditioning
 

I think we may have a Positive result here. Yesterday draining at 580mA to 155v took 1.17 hours, so to get to 155v cost .58mAx1.17 hours. Or less than an amp hour.

today, at a much lower draw (390) it took 5.25hours, or just over 2 amp hours!
One of the bad volt taps appears rehabilitated almost entirely, the one which was at 8v while the rest were at 14.5 is less than 5% off from the others.

I think Steve is offline for the weekend, can anybody comment on draining to 144v and then letting the pack sit for 3 hours and then continuing the drain?

Re: HCH1 DIY IMA Reconditioning
 

Steve is not offline. He just didn't see your post, and he has a lot of other things to do.

First, no, but overcharging is necessary to ensure that ALL cells are at 100% SoC - THAT part is critical..

Second, same answer as the first. It's critical that all cells start at 100% SoC. Cells that are reversed for > 50% of their available capacity run a high risk of damage. Starting at 100% SoC minimizes the chance of exceeding the 50% reversal. We discussed this earlier - if a cell has 5000mAh of capacity, reversing it for > 2500mAh will damage it. If the cell isn't fully charged to deliver that 5000mAh, but is only at say 3000mAh (60% SoC), rather than taking a total of 7500mAh before damage occurs, it's 5500mAh

EDIT: The weakest tap at very low voltage has likely never been fully charged, and you run the risk of damaging it with deep discharges due to excessive capacity extraction in the reversed polarity condition.

As-removed packs are wildly out of balance with some cells near 100% SoC and others near 0% SoC. Failure to get the emptiest cells to full runs greater risk of damage.

Your experience with your dustbuster is no different except that NiMH are dramatically more resistant to voltage depression.

5% is very bad. You need to deal in absolutes. Any tap that is 0.2V LOWER than the HIGHEST tap reading is suspect - particularly when operating above 144V.

It may be an indication of a failing cell, or it's just the fact that you've never driven it to 100% SoC.