
TYPICAL PEUKERT'S EXPONENTS
Surrette and Rolls Batteries
Model | Volts | Res. Min. | "n" | |
6 | 345 | 208 | 1.42 | |
6 | 350 | 225 | 1.54* | |
6 | 395 | 262 | 1.72* | |
24/90 | 12 | 165 | 90 | 1.16 |
27/12M | 12 | 190 | 112 | 1.23 |
30H/108 | 12 | 230 | 108 | 1.08 |
HT/4D | 12 | 348 | 170 | 1.15 |
HT/8D | 12 | 450 | 221 | 1.20 |
*Use Max allowed "n" of 1.50
CALCULATING PEUKERT'S EXPONENT
Example of using Reserve Minutes @ 25 amps
and the 20-hour rate to calculate "n".
First convert Reserve Minutes to hours, then find the discharge current at the
Trojan T-105:
Reserve Minutes = 447 min @ 25 amps.
t1 = 447 min = 447/60 = 7.45 hrs
I1 = 25 amps
t2 = 20 hours
I2 = 225 amp hours/20 hours = 11.25 amps
n = | log t2 - log t1 | = | log 20 | - log 7.45 | 1.301 | - 0.872 | = 1.24 | |||
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log I | - log I | log 25 | - log 11.25 | 1.398 | - 1.051 | |||||
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