On Jul 27, 6:06*pm, Larry wrote:
GeoffSchultz wrote in news:23fd18df-7c36-
:

According to Caterpiller, who makes my
153-5720 batteries, the charging rate should not exceed 5% of the CCA,
which is 1500 A per battery. *That 3000 CCA total or a max charging
rate of 150A.

All wet. *DEEP CYCLE house batteries with a low count of really thick
plates you eat away slowly with load are NOT Caterpillar starting batteries
that have huge cranking capacity for a few seconds because they have
massive arrays of really THIN plates creating massive surface areas.

They aren't even the same batteries!

Yeah, you can charge huge diesel cranking batteries in a half hour with a
massive charger because they have MASSIVE SURFACE AREAS to charge!

You CANNOT charge DEEP CYCLE, thick plated, much less surface area
batteries in this manner....another whole different animal entirely.

But, it's your boat. *Buy the biggest goddamned charger on the planet and
charge the Deep Cycles with it at 25VDC in 10 minutes....

Perhaps you should read about the batteries before opening your
mouth. They are deep cycle batteries.

http://www.cat.com/cda/components/fu...&x=7&id=241185

-- Geoff

On Mon, 28 Jul 2008 03:49:52 -0700 (PDT), GeoffSchultz
wrote:

On Jul 27, 6:06*pm, Larry wrote:
GeoffSchultz wrote in news:23fd18df-7c36-
:

According to Caterpiller, who makes my
153-5720 batteries, the charging rate should not exceed 5% of the CCA,
which is 1500 A per battery. *That 3000 CCA total or a max charging
rate of 150A.

All wet. *DEEP CYCLE house batteries with a low count of really thick
plates you eat away slowly with load are NOT Caterpillar starting batteries
that have huge cranking capacity for a few seconds because they have
massive arrays of really THIN plates creating massive surface areas.

They aren't even the same batteries!

Yeah, you can charge huge diesel cranking batteries in a half hour with a
massive charger because they have MASSIVE SURFACE AREAS to charge!

You CANNOT charge DEEP CYCLE, thick plated, much less surface area
batteries in this manner....another whole different animal entirely.

But, it's your boat. *Buy the biggest goddamned charger on the planet and
charge the Deep Cycles with it at 25VDC in 10 minutes....

Perhaps you should read about the batteries before opening your
mouth. They are deep cycle batteries.

http://www.cat.com/cda/components/fu...&x=7&id=241185

-- Geoff

As a matter of interest you might want to read CAT
Safety_Bulletin_No_23_MF_Battery_Explosions.pdf

The safety bulletin reads in part:

This Safety Bulletin provides the reader with a safety awareness of
Battery explosions with certain Caterpillar Maintenance Free
batteries.

Location Type: Certain applications using Caterpillar Maintenance Free
batteries part number 153 5720

Event: Lead acid Battery explosions caused by specific application,
operational or maintenance activities, with potential to injure
people, and damage plant and equipment.

Model: Hastings Deering(Aust) Ltd are aware of reports of battery
explosions with the following plant types/models:
Caterpillar G3516 generator sets; 3508 generator sets; Hitachi
EH-450 Dump Truck

Background
Maintenance Free (or low water loss) battery explosions can be
triggered by a number of factors. Some common cause factors are well
known and applicable to most types of lead acid storage and starting
batteries.

Some explosions appear to be caused by uncommon events. A recently
reported battery explosion coincided with the use of compressed air to
blow out a battery compartment of a Hitachi off highway truck.
Static electricity discharge is an unlikely but possible ignition
source in this case.

Hastings Deering experience
Following a 153 5720 Maintenance Free battery explosion during engine
starting, we examined 56 batteries of this part number in service and
at risk. The application was starting batteries for G3516/G3520
generator sets in continuous service.

The causes of battery explosion we found we

1) High battery operating temperatures
2) Over charging due to charger voltage regulation unsuited to the
application
3) Significant loss of battery electrolyte not apparent to maintenance
persons.

Discussion
1) High battery operating temperatures
Test measurements showed that with 38 deg C ambient a sample of
batteries were operating in excess of 50 deg C with average battery
temperature being 52 deg C. Some battery top covers were measured at
65 deg C.

2) Over charging
High battery operating temperatures require a reduced charge rate.
The nominal 27.6V charging voltage was reduced to 25.8V, based on
recommendations from a major battery manufacturer.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce in Bangkok wrote in
:

As a matter of interest you might want to read CAT
Safety_Bulletin_No_23_MF_Battery_Explosions.pdf



Naw....don't confuse him. Caterpiller batteries are different. They're
made for 500 amp charging for hours. That won't cause them to explode,
boiling the electrolyte like that....

They won't listen.....

On Jul 28, 4:16*pm, Larry wrote:
Bruce in Bangkok wrote :

As a matter of interest you might want to read CAT
Safety_Bulletin_No_23_MF_Battery_Explosions.pdf

Naw....don't confuse him. *Caterpiller batteries are different. *They're
made for 500 amp charging for hours. *That won't cause them to explode,
boiling the electrolyte like that....

They won't listen.....

Bruce: Thanks for the pointer. I already follow all of the
prescribed suggestions. It appears that the problem is excessive
charging voltages in high temperature environments. I utilize
temperature compensated chargers.

Larry: I know that you try to be helpful, but who do you think that
I'll believe: you or the engineering documents describing the
recommended charging scheme? I even calculated the temperature
correcting coefficient per their documents and e-mail with the
engineer who supports the battery. You often act like you're the
definitive/last-answer to battery questions, and perhaps you should
realize that you're not.

-- Geoff