Ericsson MASTR III 344A3168P1, Maintenance Manual

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CH1L CH1M CH1R CH3A
344A3168P1 10 AMP CHARGER, 60 Hz 1 1
344A3168P2 10 AMP CHARGER, 50 Hz 1 1
344A3696G1 CHARGER KIT 1 1
344A3696G2 CHARGER KIT 1 1
19C852074P1 SUPPORT 1 1 1 1
19C852074P2 SUPPORT 1 1 1 1
19D903719P1 BATTERY STANDBY SHELF 1 1
19C852193P1 BATTERY COVER PANEL 1 1
19D903635 INTERCONNECT DIAGRAM X X X X
19D902845P5 APPLICATION ASSEMBLY X X
19D424751P6 APPLICATION ASSEMBLY X X
344A4051P1 INSTALLATION INSTRUC. X X
344A3168 CHARGER SPECIFICATIONS
Input Voltage Range P1: 121 Vac
±
10% for trickle charge or full rated charge
(For Normal Operation State) 121 Vac
±
20% for trickle charge only
P2: 230 Vac
±
10% for trickle charge or full rated charge
230 Vac
±
15% for trickle charge only
Input Voltage Range < 70% of nominal line voltage
(For Emergency Power State)
Line Voltage Surge Protection P1: 150 Vac rated M.O.V.
P2: 275 Vac rated M.O.V.
Charger Output Voltage 13.6 Vdc
Rated Charger Current 10.0 amps
Load Current Knee 11.0
±
1.0 amps
Short Circuit Current 4.0 amps max
Charger Output Voltage Ripple < 100 mV p-p (@ + 25°C)
< 200 mV p-p (@ - 30°C)
Duty Cycle (Full Charge) 100% for 8 hours
(Trickle Charge) 100% continuously
Status Line Output
(Normal Operation) 23.5
±
0.5 Vdc
(Emergency Power) Impedance >1 Mohm
Current Sourcing Capability 33 amps max
(A+ to SW A+ port in
Emergency Power State)
Deep Discharge Cutout Voltage 10.5 Vdc
Temperature Range -30° to +60°C
Weight 22 lbs.
EMERGENCY POWER OPTION
SYSTEM DESCRIPTION
The 344A3168 series of chargers are designed to interface
with 19A149978P1, Rev. B or later, or 19A149978P2, Rev. A
or later series power supplies. To retrofit the charger with
19A149978P1, Rev. 0 or A power supplies, or 19A149978P2,
Rev. 0 power supplies, Field Mod Kit 344A4123G1 with mod
instructions 344A4124P1 must be used. Under normal operat-
ing conditions (defined as having the nominal input line voltage
plus a tolerance) the relays K1, K2, and K3 are energized.
344A3168 becomes a charger, providing a full charge of up to
10 amps out of the A + port to the battery system at a constant
voltage until the battery system is fully charged. If the charger
attempts to source more than 10 amps because, for example, a
battery has been deep discharged, then the charger’s current
foldback circuitry will drop the charger voltage for a short time
until the battery has been recharged enough to no longer sink
more than 10 amps. The charger will then revert to providing a
constant voltage charge. The charger then maintains a trickle
charge indefinitely on the battery system to maintain a full
charge.
Without the emergency power options, the power supply’s
10 ohm, 50 watt bleeder resistor R1 is tied to ground through an
external strap, P802. With the emergency power options, P802
is removed, allowing K3, the SW GND (switched ground) relay
in the charger to ground the bleeder resistor through J2-3 to
provide normal operation of the supply. The STATUS line (J2-
1) provides a + 24 Vdc signal to the alarm tone circuitry indi-
cating the system is in the normal operating state.
When the input line voltage drops below 70% of the nomi-
nal line voltage, the charger reverts to the emergency power
state. Current, instead of being sourced from the A + port to the
battery system, is now being delivered from the battery. K1 de-
energizes, and K2 remains energized. This allows up to 33 amps
to flow from the battery to the charger A + port, out of the SW
A + (SWitched A +) port and through the SW A + port of the
power supply. The current is then fed through the power sup-
ply’s load fuses and out through the harnesses to run the base
station’s power amplifier and receiver/system circuitry. K3 also
de-energizes, opening the bleeder resistor circuit. This removes
the 1.2 amp load on the battery that would have drained the bat-
tery at a faster rate. The STATUS line becomes an open circuit
to the alarm tone circuitry indicating the system is in the emer-
gency power state.
When the battery system has discharged to approximately
10.5 Vdc the charger de-energizes K2 to prevent a deep dis-
charge of the battery system. This is important for both gel cells
and automobile batteries but especially for automobile batteries.
Any deep discharge of an automobile battery will affect its ca-
pacity to store energy. Several deep discharges would result in a
premature replacement of the battery. The charger then sits in
"limbo" waiting for the normal operating range line voltage to
reappear.
If the charger has:
1) an overheating condition, or
2) an overvoltage condition which would lead to an over
heating condition;
then the charger will revert to a "shutdown" mode until condi-
tions return to normal. Under normal conditions the SHUT-
DOWN line (J2-2) is at 0.1-0.2 Vdc. When the charger reverts
to the shutdown mode, J2-2 rises to around 2-3 VDC. The
charger remains in shutdown until the condition is corrected.
CIRCUIT DESCRIPTION AND
THEORY OF OPERATION FOR THE
344A3168P1 OR P2 BATTERY
CHARGER
GENERAL
The 344A3168 battery charger has been designed to provide
both system battery charging and relay switched, emergency
power via automobile battery or gel cell battery for the
MASTR II/IIe/MIII series of base stations.
The charger monitors system line voltage for possible inter-
ruptions. During normal operation, the charger maintains full
charge on the emergency power battery by providing a trickle
charge current. In the event of a power source interruption, the
charger sets the STATUS line to the emergency power mode,
discontinues battery charging, and switches the battery on line
to provide emergency backup power for the base station.
Extreme care must be exercised when using an automo-
bile battery for backup emergency power. The automo-
bile battery must not be installed in the base station
cabinet because a buildup of acidic fumes during out-
gassing would damage the base station circuitry. Also,
there could be a dangerous buildup of hydrogen gas in
the cabinet during outgassing which could lead to an
explosion. Even for an automobile battery correctly in-
stalled outside of the cabinet, there could be a danger-
ous concentration of hydrogen gas if the room is not
properly ventilated. It may even be necessary to provide
a "hood" over the battery and an exhaust system to vent
the gas to the out-side world. Follow OSHA (or other
equivalent agency) safety construction rules to deter-
mine a proper design.
WARNING
LBI-38625
2