(help)battery chargers

[Yoel2630]

We had a problem with our chargers and now they don't work (not very clear what happend)

Anyways the reason I came here is because we want to buy a new charger and were told that there are a few options and some better then others.
So here some questions to direct you:
What are my options?
What kind of requirements do FIRST battery chargers need?
What do you use? and if for some special reason please specify why
Where can I get a charger?
How much should a charger cost?
(you don't have to answer all the questions if you don't know)

Thank you for helping
Yoel and team 2630

[EricH]

According to last year's rules, you have to use a 6-amp rated automatic charger. Note that the rules may change for 2009. Typically, FIRST includes a charger in the kit of parts, but those are not necessarily the only legal chargers.

[DonRotolo]

You need to decide if you want a competition-legal charger or something to just charge batteries. Please note that the competition-legal chargers are specified so that you don't damage the batteries by charging too fast, so it does make sense to heed their advice.

That being said, only the 2009 rules will tell us what is legal. It is a reasonable bet that a 6 ampere (max) fully-automatic charger would be good.

We use several chargers, some identical to the Kit chargers, some almost so. The recent kit chargers have nice lights and stuff, but the old chargers seem to be more resistant to user error.

A charger can be had at automotive and marine stores, including sears, JC Whitney (online) and perhaps large wall-o-china-mart stores.

A charger like that might cost about $50, more or less.

[Leav]

Yoel, I searched around a little and found these:

http://www.harborfreight.com/cpi/cta...emnumber=45005
http://www.harborfreight.com/cpi/cta...emnumber=95533
http://www.harborfreight.com/cpi/cta...emnumber=94088

Can someone comment on these? are these just junk?

(But Harbor Freight only ships to the US.)
Maybe you could talk to Avi and see if he's in the US anytime soon.

-Leav

[DonRotolo]

Any of those would be fine, although the middle one is limited to 2 Amps. They are Harbor Freight quality, which is OK if you understand what you are getting. Surely ones similar are available throughout the world, ya just gotta look.

[Yoel2630]

Thank you guys

From what I understood car battery chargers and model airplane and model helicopter battery chargers seem ok.

They are available in Israel but the cost is much higher than in the USA.

[Al Skierkiewicz]

Yoel,
There is at least one or two other threads that discussed chargers. I think I listed the charger we use. It is a 5 battery charger @5 amps each port and available from McMaster Carr.

[Doug G]

Picked up our first Battery Load Tester today. How we got by 8 years without one is crazy. But after so many battery charging problems last year - I sure hope this helps sort out what is good from what is not. We used a battery mount that had it laying down through the three competitions last year, and I think the shock load on the plates inside resulted in cracking so that we thought they were good but under load they just could keep up the voltage and cost us two matches in Atlanta.

So for teams... Go to your local Napa Auto parts and get a Battery Load Tester for about $50!!

[Leav]

Hi Al,
Couldn't find that post, or the charger on McMaster.... would you mind re posting the model?

Thanks!
-Leav

[Al Skierkiewicz]

Originally Posted by Leav

Hi Al,
Couldn't find that post, or the charger on McMaster.... would you mind re posting the model?

Thanks!
-Leav

Leav,
I went looking on McMaster and Grainger and couldn't find it. I will ask one of the other mentors if he remembers and get back to you.

[Joe Ross]

Originally Posted by Al Skierkiewicz

Leav,
I went looking on McMaster and Grainger and couldn't find it. I will ask one of the other mentors if he remembers and get back to you.

http://www.chiefdelphi.com/forums/sh...09&postcount=7

[AdamHeard]

Originally Posted by Doug G

Picked up our first Battery Load Tester today. How we got by 8 years without one is crazy. But after so many battery charging problems last year - I sure hope this helps sort out what is good from what is not. We used a battery mount that had it laying down through the three competitions last year, and I think the shock load on the plates inside resulted in cracking so that we thought they were good but under load they just could keep up the voltage and cost us two matches in Atlanta.

So for teams... Go to your local Napa Auto parts and get a Battery Load Tester for about $50!!

Does anyone know if a battery laying horizontally can damage the plates? I've heard it makes no difference.

[Al Skierkiewicz]

Originally Posted by AdamHeard

Does anyone know if a battery laying horizontally can damage the plates? I've heard it makes no difference.

The manufacturer says you can use the battery in any configuration. I personally would recommend you charge it with the terminals up. Charging in any configuration is likely OK but I avoid upside down to be sure that fluid is not covering the vents during charge.

[grambo]

The biggest thing to look for in a charger is the "three stage" charging. Essentially what that means is that the charger will go thru these stages: First, "bulk" stage: hit the battery with 6amps and wait for the voltage to rise (near about 14.6V). Second, hold the voltage at that "overcharge" mark (14.6V) until the current drops to 1/10th of that original 6amps. Finally, drop the voltage to the "float" mark (about 13.5V) pretty much assuring that when you unplug the battery from the charger it is as full as it can be.

Cheaper chargers will do various things, generally like if you have a lab supply and set it for 13.5V, 6A and then hook the battery to it, it'll dump 6A intot he battery until it gets to 13.5V, and simply taper the current back as the battery reaches that point. These will generally have timers and aren't very good for cyclic use of the battery as you miss out on the overcharge part of the cycle. ...for "standby" use, these chargers are perfectly fine, like for emergency lights and such.

[Al Skierkiewicz]

The multi charger works for us. It hangs on a wall or a stand we have made, it is compact taking up about half the space that six chargers would and weighs less. It has a little less heat output, keeps the pit neater and we don't worry which charger a battery is connected to since the cables are color coded. It is a luxury admittedly, but one that has worked for us. Since we have two schools and two facilities, it allows us to distribute KOP chargers to other areas.