Lamar Technologies CA 1550 - Manual (Page 10)

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C. FAIL
The battery fails the discharge test because of insufficient capacity if the voltage
decreases to below the preset voltage cutoff (usually 0.1-0.3 volts below preset
cutoff depending on the rate at which battery voltage is falling), before the timer
times-out, the “Fail”(14 Red) Led illuminates, Meters and Timer Hold (Freeze),
buzzer sounds. The actual ampere hour capacity of the battery is indicated by
Amps x Time divided by 60. Ampere hours are also directly read on the amp-
hour Meter (16). This is the actual ampere hour capacity of the battery.
TEMPERATURE CUTOFF
A temperature sensing plate is provided which will Cut off the charge or
discharge current when the battery reaches 113 degrees F. This is a cautionary
indication to observe this battery. Plug the temperature plate into test points
marked “Overtemp Cutoff Thermostat.” If not plugged-in, charge or discharge
proceeds without temperature cut-off.
Note: If temperature cutoff occurs, the Ampere Hour Meter keeps its reading.
The timer continues to run, while the battery is cooling (it may time-out). When
the battery cools, the charge or discharge resumes (if its not timed-out). A new
time setting may be needed to achieve the required ampere hours.
D. SPECIAL ADJUSTMENTS
For a battery of higher capacity than 50 ampere hours, set the time of discharge
proportionately higher, e.g. for 60 Ampere hours- Set charge to 50 amps, and
timer to 72 minutes, which is 50 A x 72 minutes = 3600 amps min. divided
by 60 = 60 amp-hours. For 70-ampere hours, set unit to 50 amps, timer to 84
minutes. (Or for a 60 Ampere hour battery you could set the amps at 30 and the
timer for 120 minutes. This is discharging at the 2-hour rate. Then the voltage
cut-off should be 19 volts instead of 18. See NAVAIR 17-15BAD-1 for special
case-by-case situations.
IV. CONDITIONING CHARGE
Lead acid batteries become sulfated either because they have not been charged for a long
period of time (many months) or left discharged for even one or two days.
They have virtually no capacity and will not accept a charge, usually going up to full
“chemical” voltage very quickly with little charge current. They can usually be
recovered with a “conditioning charge” procedure as follows: