Placing Charger In Service; Adjustments Of Float & Equalizing Charge; Manual Equalize Timer - HindlePower SCRF SERIES Operating And Service Instructions

4. PLACING CHARGER IN SERVICE

a. With the AC and DC breakers OFF and the system in float mode, install the charger making AC
and DC connections, as described in Section II, 3, and in accord with local regulations as they apply.
b. After connecting the lead from the positive (+) battery terminal to the positive (+) terminal on the
charger and the lead from the negative (-) battery terminal to the (-) terminal on the charger, observe the
voltmeter. It should read the correct polarity and be approximately the battery open circuit voltage (this is
2.0 volts per cell for lead-acid batteries and 1.2 volts per cell for nickel cadmium batteries). For example, a
60-cell lead-acid battery should read about 2 x 60 cells = 120 volts. This is a check that all cells are in a true
series (none connected in reverse) and all connections are tight. The open circuit voltage should be about 8
to 10% below the rated float voltage.
c. The charger can now be energized, by first closing the DC breaker to supply voltage for the control
circuits then closing the AC breaker. Set the charger to "float". The AC power ON pilot light should light,
and the ammeter should indicate charger output current. It is to be expected that the meter may show up to
110% current rating of the charger; the 110% being the factory setting of the current limit control.
d. The factory preset float voltage adjustment is shown on page ii and when this value is reached, the
charger ammeter should show a slow decrease in current, eventually down to a stabilized value. Please note
that whenever a charger is in a current limit condition, the output voltage is automatically reduced to a value
below the set float or equalize voltage. The voltage will not increase to normal value until the battery's state
of charge increases, causing the charger current to decrease to a value equal to or less than the rated current.
e. The factory adjustment of the equalizing charge voltage is also shown on page ii and assuming this
is as desired, the Float/Equalize switch may be switched to "Equalize", to check the charger performance at
this voltage value. If a manual Equalize Timer (option) has been included, turn it clockwise to activate the
equalize charger mode. The charger ammeter may again go up to current limit until the equalizing charger
voltage is reached. The length of time required to reach this level depends on the state of charge of the
battery, and the ampere rating of the charger versus the battery rating.
f. With the charger operating at the desired float and equalizing voltage values, the system can be
considered installed and ready for service.
5. ADJUSTMENTS OF FLOAT & EQUALIZING CHARGE (also see Section IV, 1)
a. Each adjustment is made by means of a potentiometer with a slotted shaft for a screwdriver. The
potentiometers are front-panel mounted and appropriately marked. A lock nut on each potentiometer is
provided and should be tightened after the proper adjustment is completed. This prevents any accidental
mis-adjustments of the settings. The voltage response may be slow if a rise in voltage adjustment is desired,
because the battery state of charger and connected load must be considered. Turning the shaft clockwise will
raise the voltage, and turning counter-clockwise will lower the voltage.
b. Since accuracy of measurement is important when setting float and equalizing voltages, a
precision portable VoltOhmmeter with at least 1% accuracy is recommended for these DC measurements. A
conventional VoltOhmmeter or analyzer such as the Simpson Model 260 is also satisfactory, but is not as
accurate.
c. Any setting of the float voltage or equalizing charger voltage should not be considered final until
the ammeter shows less than charger rated current, and voltage does not change after several hours of
operation.
6. MANUAL EQUALIZE TIMER (OPTIONAL)
a. This timer is provided to obtain a charge up to 72 hours, at a slightly higher value than the
ordinary float voltage. The timer may be used for recharging older batteries, or for a freshening charge on
new batteries. For a detailed explanation of operation see Section V (Customer Options).
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