ZDSO400-DR2, ZDSO400-DR4 Document N
o
. 0546.00.95-02.2 Page:9/18
the preset charging voltage has been reached, after which the power supply decreases the voltage to the
level of floating mode voltage, continuing charging with this voltage. If the battery bank is faulty, the bulk
charging is interrupted in the fault mode after the maximum, preset charging time has been exceeded or
when the permissible ambient temperature of the battery bank is exceeded.
The circuit of the ZDSO400-DR2 or ZDSO400-DR4 power supply is equipped with a LVD – an internal
switch of deep discharge implemented in the relays in their output circuits (one relay in each circuit for
powering amplifiers and one at each double outputs for powering the VAS controller). They disconnect
the outputs from the battery banks when the battery reaches the minimum permissible discharge level,
thus preventing it from further discharging and preventing it from being destroyed.
The second BD disconnector (Battery Disconnector) ensures powering continuity for additional outputs
from the rectifier in the case of short circuit of the battery terminals of the charger.
Measurement of battery circuit resistance is an additional function of the controller. The resistance
measurement takes place only in the floating mode operation. Detection of battery circuit resistance
increase caused by an increase in internal resistance of the battery or by an increase of battery
connection resistance, causes the indication for reaching high battery circuit resistance to be sent. If the
battery bank gets disconnected, the controller detects a significant increase of battery circuit resistance
and indicates a device configuration error.
The power supply is equipped with a function of voltage equalisation between batteries of each battery
string. Voltage equalisation takes place as a result of loading the half of batteries which exhibit higher
voltage, with a small current, of 100mA. This function is called for if the voltage difference exceeds 0.1V.
The use of voltage equalising circuit requires an additional connection to be introduced between the M
terminal of a given battery string and the median point of the battery itself. This system is resistant to an
incorrect connection of this connector (to an inappropriate terminal of any battery), indicating a fault in
such the situations. The lack of this connection is automatically detected which results in switching off the
voltage equalising system.
The circuit of the ZDSO400-DR2 or ZDSO400-DR4 power supply is continuously controlling the state
of circuit breakers in the output circuits provided for amplifiers and of the circuit breaker (breakers) in the
output circuit provided for the VAS controller. Fault to any of them results in a fault signal being generated
(the signalling lights on the front panel of the power supply unit are switched on and the remote signalling
to be put out), and in addition, switching on a yellow LED diode located near the faulted circuit breaker.
When the power supply unit is switched on, state of load at the outputs designed for VAS amplifiers is
checked. Lack of current consumption from these outputs is required. If any of the amplifiers has e.g. its
own power supply switched off (or faulty), which results in an attempt of switching it on using output
voltage of the power supply unit, such the state shall be detected and the relay present at this output shall
not switch on, and, in addition, fault indication shall be switched on. Relays present at the other outputs
shall simply switch on, supplying voltage to operational amplifiers.
During the power supply start, the current consumption from the output designed for the VAS
controller is only permitted. Its load present at this output, however, decreases the current provided for
battery bank charging.
NOTE:
If the system has already been switched on and any of the amplifiers starts consuming current using
output voltage as a result of fault – then leaving the power supply system in this state may eventually
result in an uncontrollable discharge of the battery, despite proper functioning of the power supply
system itself.
