Triplett Chek-A-Cell – PN: 3276 - Manual (Page 3)

INTRODUCTION:
The CHEK-A-CELL is a digital battery load tester for all types of batteries in
the 5.75 Volt to 20 Volt, 1 to 20 Amp Hour range. Rechargeable batteries that
may be tested include Sealed Lead Acid, NiCad, NiMH, Lithium Ion (Lion), and
others. Non-rechargeable (disposable) batteries may also be tested. These are
commonly Carbon-Zinc or Alkaline batteries. The CHEK-A-CELL is often used
to load test 6 volt or 12 volt sealed lead acid batteries. These types of batteries
are often used for backup power in Emergency Lighting, Security Systems, and
Uninterruptible Power Supplies (UPS). They are also used as a power source
in many portable garden tools (weed wackers, small lawn mowers, etc) and
children’s electric cars and motor bikes. NiCad, NiMH, and Lion batteries are
common power sources for portable power tools. By applying a load to the bat-
tery and measuring the battery’s voltage, the CHEK-A-CELL helps to determine
the battery’s condition.
Battery Testing Notes:
The CHEK-A-CELL contains an internal “load” for testing batteries. This load will
heat up while the battery is being tested. The test time must be limited to prevent
the load from overheating. Generally, 5 seconds is a sufficient test duration to
determine a battery’s condition. Higher voltage batteries will heat the load more
quickly than lower
WARNING!
Do not apply battery voltage to CHEK-A-
CELL for longer that 10 seconds.
Allow CHEK-A-CELL to “cool” for
3 minutes between measurements.
If testing a rechargeable battery, the battery MUST BE FULLY CHARGED prior
to the test. In backup power applications, the battery is usually under constant
charge, and should be fully charged at any time (unless just recovering from
prior usage). In other applications, make sure the battery is fully charged before
testing.
An undercharged battery will fail the CHEK-A-CELL’s test. A fault in the battery
charging circuitry could cause a battery to fail the test. Make sure the charging
circuit is operating properly.
Batteries can exhibit a “float” or “surface” charge immediately after “fast charg-
ing” or after extended standby charging. The surface charge causes the battery
voltage to be higher than normal. The surface voltage usually collapses rapidly
under load, or will gradually dissipate by itself if the battery is allowed to set for
several hours after being disconnected from the charging circuit.
Using the CHEK-A-CELL:
Disconnect the battery from the charging circuit. If the battery is wired into a
circuit, it is only necessary to disconnect one side of the battery….. either positive
or negative.
Using the test probes and observing proper polarity …..red is positive (+), black
is negative (-)….. touch the CHEK-A-CELL’s probes to the battery terminals.
Observe the reading on the digital display.
If no display is obtained, the battery may not be producing the minimum voltage
required to operate the CHEK-A-CELL (about 4.5 Volts). The CHEK-A-CELL
will not test 1.5 Volt (AAA, AA, C, or D) or 3 Volt (Lithium coin cells) batteries.
The load produced by the CHEK-A-CELL is usually to large for the typical 9 Volt
battery.
If the battery is the appropriate size, and no display is obtained, it may be “dead”
or require charging.
If a “minus” (-) symbol lights in the digital display, the polarity of the test probes
is reversed, or the battery is reversed charged. Reverse the test probes to obtain
a reading.
If testing a 6 Volt sealed lead acid battery, and the reading drops below 6.20 Volts
in several seconds, the battery is “weak” and may need to be replaced (or the
charging circuitry may have a fault).
If testing a 12 Volt sealed lead acid battery, and the reading drops below 12.40
Volts in several seconds, the battery is “weak” and may need to be replaced (or
the charging circuitry may have a fault).
If a 6 Volt sealed lead acid battery displays a voltage in excess of 6.8 volts, it has
a surface charge. If the voltage does not drop to 6.3 volts in one or two seconds,
the battery must be allowed to set for several hours for the surface charge to
dissipate.
If a 12 Volt sealed lead acid battery displays a voltage in excess of 13.6 volts,
it has a surface charge. If the voltage does not drop to 12.6 volts in one or two
seconds, the battery must be allowed to set for several hours for the surface
charge to dissipate.
Rechargeable batteries can develop internal shorts that discharge the battery.
If the battery is charged using a trickle charger (usually takes 12 to 16 hours to
charge), the internal shorts often prevent the battery from obtaining a full charge.
When tested with the CHEK-A-CELL, the battery’s voltage will be low, and it will
drop quickly, indicating that the battery is bad.