grid charger/balancer

[Eli]

Either one is fine.

[Mike Dabrowski 2000]

As Eli indicated, either of the chargers will bring back life to the pack. the important topping area of the charge is at the same 350 MA on both machines, the Overnight just gets there faster.
Update on the three chargers, they are gone already, so now I am out of grid chargers.
Sorry
The faster we get the 30 orders the faster we can get the wheels in motion on the next batch.

[Mike Dabrowski 2000]

Please read:
Using the Universal grid charger

[insightbuyer]

Hi Mike, when is the deadline for the deposits?

[Mike Dabrowski 2000]

I would really like to get the parts on order before April, but will start the ordering as soon as I get 30 people.
So the deadline is april, and depending on how close we are in firm orders, I will decide which way to proceed.

[Milanotorino]

Greetings,
I am in the process of building the basic 350ma charger and would like to confirm a couple of things before the first use. I've read through this thread until I burned out at about page 70, so I'm sure some of these are repeats (apologies).

1. DC fuse goes as near the battery as practical, should the diodes go there too? I got the 2 amp fuse because the 1 amp was out of stock. I'm assuming that won't be a problem. Is it worth having 2 fuses, one at the charger and one at the battery?

2. I think I read that it's okay to leave the fan connected. Would like to confirm this. If it's not a problem, seems it would be easy to connect to the fan wires without cutting them by using crimp on insulation displacement type connectors.

3. How risky is it to charge the battery at near 32 F temperatures? The forcast for this week is highs in the 30s and lows in the 20s. Maybe I should leave the fan disconnected? I'd rather not remove the battery and bring it in the house, but will if I must. I'm planning to do the first charge with the long probe hook-up and install a wire harness later.

4. BCM is currently disconnected. Is some sort of recalibration procedure required after charging?

5. MOST IMPORTANT: Many thanks to Mike D. for the design and sharing his knowledge!

-Dave

[JimIsbell]

Originally Posted by Milanotorino

1. DC fuse goes as near the battery as practical, should the diodes go there too? I got the 2 amp fuse because the 1 amp was out of stock. I'm assuming that won't be a problem. Is it worth having 2 fuses, one at the charger and one at the battery?

Two fuses dont increase the protection. Where it goes is immaterial. To reach 1 or 2 amps ANYWHERE in the circuit it has to reach that current EVERYWHERE in the circuit, at the speed of light. Your fuses take much, much, much longer than that to blow....LOL. Same goes for the diodes. DC in one place means DC in ALL places....again, at the speed of light.

Originally Posted by Milanotorino

2. I think I read that it's okay to leave the fan connected. Would like to confirm this. If it's not a problem, seems it would be easy to connect to the fan wires without cutting them by using crimp on insulation displacement type connectors.

This works fine. The fan circuit has a diode in it so it is protected from reverse connection. If your connection does not turn the fan, its backwards, but it wont hurt a thing.

Originally Posted by Milanotorino

3. How risky is it to charge the battery at near 32 F temperatures? The forcast for this week is highs in the 30s and lows in the 20s. Maybe I should leave the fan disconnected? I'd rather not remove the battery and bring it in the house, but will if I must. I'm planning to do the first charge with the long probe hook-up and install a wire harness later.

Colder the better (maybe somewhere below zero you might worry) as charging the battery WARMS it up. Removing the battery is NOT AN OPTION!!! Unless you just have half a day to waste and enjoy the work!!!

Originally Posted by Milanotorino

4. BCM is currently disconnected. Is some sort of recalibration procedure required after charging?

When you reconnect the BCM it will initiate a RECAL...if you mean by "disconnected" the plugs are removed.

[Eli]

You must run the fan even with temperatures that cold. The plastic battery case is extremely insulative, and the heat has no where to go without even a small amount of air flow. A battery can easily reach over 100 degrees with ambient temperatures in the 30s after 6+ hours of charging in my testing.

[JimIsbell]

I have charged mine in ambient temps of 90F with no fan at 350ma, and the warmest it got was 109F The battery is designed to go to 120F normally and back last summer, "the summer of hell", when the ambient reached 122F I was driving across north Texas and Oklahoma and the temp of the battery reached 128F with no harm done!! You will never get it that high just charging it at 350ma. even without the fan, If you decide to try high amp charging it could go into those areas, but at 350 ma, NEVER.

Eli, how did you measure the temperatures? I used the BMC gauge which gives the temp measured by the cars computer.

BTW, That trip included SF but was so tired by the time I got there and I had left my wife in the hospital in Colorado Springs for emergency surgery so had to immediately return to CS I didnt look ANYONE up. But I will be back there NEXT September as I own a condo there.

[Milanotorino]

Thanks for the advice. I wasn't clear about my reason for considering two fuses. It was for when I install a permanent wire from the battery to a connector on the aluminum panel. One fuse would be for protecting those wires when the charger is not connected. The second fuse was to protect the wires on the charger - but I guess there's no point in that if I always make sure the charger is connected to the battery before plugging it in.

I thought I read somewhere that the battery doesn't like to be charged at low temperatures.

I've been driving a little with the BCM disconnected just to see what it's like. All highway miles. The lack of power isn't as bad as I thought it would be, although the battery and brake lights at 4000 rpm is annoying.