1. Determine battery size
a. Look at data tag of battery Many times proper information including amp hour, output, etc will be listed. If you have a clean data tag, you’re nearly done! In below example, you learn it’s a 24v battery with 510 amp hour capacity.
b. No data tag? Look at intercell connector near the positive terminal.
Count the cells—there are 12 of them. 12 x 2 = 24 volt battery
The intercell connector will be stamped with battery size. In above example, it’s stamped with E085-13. After counting the cells (there are 12), we know this battery size is 12-85-13
2. Size will look something like this:
3. Determine amp hour of battery & voltage
a. Take last number (example above = 13)
i. Subtract 1 from last number (Example 13-1= 12)
ii. Divide by 2 (Example: 12 ÷ 2 = 6)
iii. Multiply by middle number (Example: 6 x 85 = 510)
iv. This is the AMP HOUR rating of the battery (Example = 510 AH)
c. Voltage = number of cells X 2 (example = 18 x 2 = 36v battery)
4. Determine input phase (single/three phase)
5. Take AMP HOUR ÷ 7 = (510 ÷ 7 = 81).
Recommend 80 amp charger. Or round up to 100. Should go much farther than 20 amps over (AH ÷ 7 ) formula. Note the charts on charging time.
6. Pick a charger from appropriate table
SERIES 3NAS-T ADVANCED
- How to Make a Battery – tutorial for how to make batteries using fairly common household items