2
3. INSTALLATION
a.
Location:
Select a clean, dry location for the battery charger. It may be located in the battery room, but not over the
battery, and must be upright. The openings for ventilation in the top, bottom and sides of the cabinet should not be
obstructed, as they provide cooling and ventilation. Ambient temperatures between 32 °F and 122 °F, and elevations up
to 3,300 feet above sea level, will not affect the performance of the charger. Operation at higher temperatures, or at
higher elevations, is possible if the output current limit is reduced.
b.
Input Wire Sizes (recommended):
Size the ac input wiring to the UMC per the National Electric Code (NEC) and
local (site) codes, for the trip rating of the UMC ac input circuit breaker (CB1). The UMC is capable of connections of
120V, 208V, 240V or 480V (60 Hz) ac single phase. Consult the I/O panel jumpers and connection input for each
power source required. An I/O panel jumper diagram is located on the inside front panel of the UMC. See also the
electrical schematic (
JE5039-##
) and connection diagram (
JE5040-##
) supplied with this operating manual.
130V-25A SINGLE PHASE
AC INPUT VOLTAGE
WIRE SIZE
FULL LOAD INPUT CURRENT
120 **
8 **
32A **** (reduced output only)
208/240 8
34A/30A
480 14
16A
130V-50A SINGLE PHASE
AC INPUT VOLTAGE
WIRE SIZE
FULL LOAD INPUT CURRENT
120 **
6 **
65A ** (reduced output only)
208/240 6
61A/54A
480 10
30A
** 120Vac input requires the output current reduced to 50% so not to exceed input breaker rating
c.
Output Wire Sizes:
10-25 Ampere unit: use #8 AWG wire
10-50 Ampere unit: use #6 AWG wire
Connect the dc cables, making sure positive (+) and negative (-) polarity is maintained.
4. POWERING UP
a.
With the ac and dc breakers (CB1/CB2) OFF, select desired voltage required for bus or battery (24V, 48V or 130V).
b.
Reduce the OUTPUT CURRENT LIMIT ADJUST control (R12) to desired level. This adjustment will limit output
current. This is helpful for two reasons. Temporary dc lines are often used to connect to the dc bus, and large wire may
not be available for quick installation in an emergency. Also, the input feed may need to be connected to a source with
limited current capability. Reducing the output current will also limit input current.
c.
Set VOLTAGE CHECK switch (SW2) to "CHARGER VOLTAGE". This will allow the user to see and adjust the
battery charger’s output voltage prior to being connected to the batteries.
d.
The charger can now be energized, by first closing the ac breaker (CB1). The "AC ON" lamp (DS01) will light. The
front panel meter indicates the charger voltage. With the dc breaker (CB2) off, there will be no current flowing.
e.
Adjust the OUTPUT VOLTAGE control (R5) to desired charging voltage. This control allows for adjustment for a
wide variety of battery banks.
f.
Switch the VOLTAGE CHECK switch (SW2) to "BATTERY VOLTAGE". The dc voltmeter (M2) will now indicate
the battery voltage and the user can compare the battery voltage and the charger voltage before turning on the dc breaker
(CB2). The meter will also display a "-" if the battery is connected in reverse polarity. Verify that the battery polarity is
correct before proceeding.
g.
Turn on the dc breaker (CB2). If the charger’s voltage is higher then the battery voltage, current will flow. You may
need to rotate the OUTPUT CURRENT LIMIT ADJUST control (R12) to allow current to flow.
h.
Increase the OUTPUT CURRENT LIMIT ADJUST control (R12) to desired current level. The battery charger will be
in current limit until the battery’s voltage reaches the same level as the battery charger. Current limit adjustment needs
to be set with current flowing into the batteries. Do not set the current limit higher than 110% of current rating of the
charger.
