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CONCEPT AND DESCRIPTION OF OPERATION
The Model 612A is a microcomputer controlled intelligent instrument de-
signed to dynamically test 6 and 12 volt sealed, lead acid batteries, with ca-
pacities ranging from 2 to 24 amp-hours. While the instrument is connected to
a battery, it is continually measuring the battery terminal voltage and report-
ing acceptable voltage ranges for various conditions. The microcomputer also
controls time intervals and current levels during the dynamic load phase of the
test. Throughout the remainder of this manual, all values enclosed in paren-
theses () refer to 6 volt mode operational values.
A battery test is accomplished in two phases:
#1. Observe the Static Test Indications
Connect the Model 612A to a battery to start the Pre-Load Static Test
phase. To test the battery charging circuit, leave the charging leads connected
to the battery during the first phase of this test. Once the analyzer has dis-
played the status of the charging circuit, a charge lead should be removed to
continue testing the battery alone.
The analyzer draws its standby operating current, approximately 24 ma. (23
ma. ), from the battery under test. If the battery does not have sufficient power
to operate the tester, it is definitely not serviceable! During this phase of the
test one of the green leds on the “OK TO TEST” bar will light indicating
whether the analyzer is running in 6 or 12 volt mode. One of the four indica-
tors beneath the “PRE-LOAD STATIC TESTING” label will also light corre-
sponding to one of the following voltage ranges:
CHARGE TOO HIGH/OPEN BATTERY
This indicator lights when the battery charging circuit is delivering a voltage
which will damage the battery, or the battery may have an “open” cell, thereby
not providing a suitable load for the charger. In either case, this must be
addressed before proceeding.
NORMAL CHARGING VOLTAGE
The indicator lights when the battery voltage is within an acceptable range of
voltage for a charged battery while connected to a properly functioning charg-
ing circuit. This indicator may remain on for a short period of time after the
charge circuit is disconnected as the battery voltage gradually decays to its
non-charging level. This is the normal display for a battery connected to
the charging circuit.
Yellow
Green
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Some batteries will show normal voltage when checked with a voltmeter, but
will not supply a significant amount of current. These batteries may display a
number of unexpected results when connected to, or tested by, this Analyzer.
Listed here are some of these indications- ALL OF WHICH SHOW THAT
THE BATTERY IS DEFECTIVE!
a. A voltmeter reads voltage in the normal range, but no lights come on
when Analyzer is connected, or one or more lights flash momentarily and
then go out.
b. A voltmeter reads voltage in the normal range, but the red “BAD” light
shows when the Analyzer is connected.
c. The static test shows “NORMAL CHARGED BATTERY”, but all lights
go out completely when dynamic test is initiated.
d. The static test shows “NORMAL CHARGED BATTERY”, but lights
flicker briefly when dynamic load test is initiated, then return to the static test
condition. This indicates that the Analyzer is not performing the dynamic
test, but in reality the battery voltage is dropping so low under load that it
resets the Analyzer to the static test mode.
The time required for any particular battery to charge from “GOOD” to “MAR-
GINAL”, and then possibly to “BAD- DO NOT USE”, gives some indication
of the battery’s ability (or inability) to supply energy. If a battery starts the
load test as “GOOD” and switches to “MARGINAL” near the end of the test
(about 45-60 sec.), it is just approaching the end of its useful service life. A
battery that indicates “MARGINAL” immediately upon the start of the load
test is definitely suspect. Remember, this Analyzer uses only 2% of the battery’s
rated capacity during a single test. A fully charged, nearly new battery will
indicate “GOOD” for at least 10 to 20 load cycles.
In situations where it is difficult or impractical to disconnect the battery from
the charging circuit, load testing the battery while it still connected to the
panel should be o.k., except where poor design of the panel or power supply
allows the high load of the dynamic test to overload the charging circuit and
blow a fuse. If a fuse blows during testing, disconnect the battery before test-
ing the battery again on this panel and all other panels of identical model.
The 612A contains a high-temperature shut down circuit. When the internal
temperature exceeds 140 deg. F, the Analyzer will reduce the heat producing
current load and extend the test time to still draw the same total load from the
battery. This extended test time can approach 15 minutes at the higher A.H
settings.