Crown Battery 18-90VTA-27

Warning: This procedure requires trained personnel!

Enter the current battery charge in amperes

If the charger is rated higher than the connector on the battery, proceed with the following modifications:

After modifications, adjust the charger settings as follows:

Select the adjusted charger setting

Sign off on the battery opportunity charging

- Lead Acid Motive Power Batteries can become unbalanced or sulfated if they are not recharged or equalize charged on a regular basis

Likewise over-discharging or unbalanced discharge can cause low uneven cell voltages. The treatment for restoring the battery to its full potential involves charging and discharging the battery in a very tightly controlled manor

This is a last resort remedy in order to salvage a battery that's been allowed to get into this condition. This may or may not be successful, as sulfate is extremely hard to remove from the cell plates and if let in this condition, may not be reversible

A. Charge the battery as normal to a fully charged condition.

B. Record all individual cell voltages and specific gravities. These readings will be used later to measure how successtul the treatment was.

C. Starting with a cool (less than 80°F) fully charged battery, charge the battery at 2.5 amps per 100 amps of battery capacity. A 24-85FC-21 has a capacity of 850 A.H. Therefore the charge rate would be 21 amps. Charge the battery for at least 24 hours. Stop the charge, if the battery temperature goes to 120°F or higher.

A. Let the battery cool back down to about 80°F

- A capacity test enables you to determine the capacity a battery actually delivers as compared to its rated capacity. This test can help determine if a battery should be repaired or replaced. When a battery delivers less than 80% of its rated capacity, the remaining capacity will decrease with each additional cycle

- It should be replaced before its cells fail and cause low-voltage operation of the vehicle, which can cause damage to the trucks electrical system

- A capacity test is performed by discharging a fully charged battery at a fixed rate (see chart on page 30) while monitoring specific test conditions, methods and procedures

- The six-hour rated discharge time is based on an electrolyte temperature of 77°F (25°C). Any deviation to that temperature, a correction to the six-hour rated time must be made

PROCEDURES FOR CAPACITY DISCHARGING:

1) Battery must be fully charged.

2) Specific gravities must be at manufacturers specifications, otherwise they must be adjusted accordingly.

3) Battery should be allowed to cool down prior to testing. Ideally, the temperature should be 75°F to 85°F. Otherwise the voltages will be affected by the temperature and the capacity must be temperature corrected.

4) Battery should be discharged within 24 hours of completion of charging and acid adjustment.

Check uniformity of construction and content in each cell

Check if some cells take less charge than others

Check if cells with a lower state of charge are up to the same level as the others

Check if cells with a higher state of charge are somewhat overcharged

Enter the frequency of equalization

Check if unnecessary equalizing charges are consuming electricity

Check if unnecessary equalizing charges are causing significant loss of battery life

- A certain amount of water loss is normal in all batteries and it should be replaced with "pure" tap or distilled water. In some areas around the country, tap water may contain chemicals or other impurities harmful to batteries. If water is needed, add just enough to bring the electrolyte to the proper level. Batteries should be filled only at the end of the charging cycle

- Overfilling is the most common error made when watering and it can cause tray corrosion. Since tray corrosion can cause extensive damage to batteries and vehicles, extreme caution must be taken to avoid overfilling the batteries

- Motive power battery trays are mostly made of steel that is protected with an acid resistant coating

Regardless of how good the coating is, if a break in the coating exposes the steel tray to sulfuric acid spilled from the battery, the acid will corrode the tray. How quickly the tray corrodes depends on how much and how often acid is spilled on top of the battery and how often the battery is cleaned

- The major cause of tray corrosion is overwatering or overfilling a battery. When overfilled, the electrolyte will spill on top of the battery. Although the water in the electrolyte will evaporate, the highly concentrated acid solution remains and gives the appearance of dampness. If the acid is not removed, the tray will eventually corrode

- To prevent corrosion, batteries should be cleaned any time the accumulation of dampness or acid becomes significant

- A good technique to follow while watering batteries is to use a flashlight focused on the vent hole being watered. Visually watch the electrolyte level rise and stop watering the instant the proper level is reached

- Each cell is filled the same way. Cell filling equipment that automatically fills batteries to the proper level is available