Battery Charger / DC Rectifier
High Protection
The rectifier is SCR controlled AC/DC rectifier with input isolation transformer and with automatic constant voltage and constant current ability. It comes with 6 Pulse or 12 pulse design options depending on user requirements. The advantages of employing 12 pulse rectifier in industrial UPS systems are to have lower THDi (<10%) and higher pf at input (>0.9) as well as to secure redundancy since 12 pulse rectifiers are designed with one delta and one star connected transformers, so the unit itself behaves as two redundant rectifiers by its nature. Output current, battery current, boost and Float Charge Voltages are adjustable on the user-friendly control panel. Detailed alarm indicators help you to monitor all alarms from the front panel and monitor the auxiliary contacts from the MIMIC diagram. On LCD panel, all key parameters can be set, and real time base events and failures can be tracked remotely via RS 232 / RS 485 port or Modbus.
Features at a Glance
  • Adjustable Timer for Boost Charging
  • Adjustable Boost and Float Charge Voltages
  • Automatic Boost Charge Selection according to boost / float current set value
  • Adjustable Rectifier Output Current and Battery Charge Current
  • LCD Display for DC Load / Battery Voltage , DC Load / Battery Current , Input AC Voltage / Line Current / Frequency
  • Event History for all Electrical values and failures
  • Automatic and Manuel Battery Test
  • Boost inhibit facility for interlock redundant application
  • Output Filter Inductor and DC Longlife Capacitor
  • Electronic Over / Under Voltage, Over Current and Short Circuit Protections
  • Isolated Output by Input Transformer and output halleffect current module
  • Parallel Redundant Operation
  • Boost and Float dropper control output for Ni-Cd and Lead Acid Battery
  • Input Filter and input surge Voltage protection
  • Internal Over Temperature protection
  • Temperature Compensation for Battery
  • Low Battery Indication and Alarm contacts
  • Rectifier Failure Indication and Alarm contacts
  • Rectifier Over Voltage Indication and Alarm contacts
  • Over Temperature Indication and Alarm contacts
  • Line Failure Indication and Alarm contacts
  • Input MCB Indication and Alarm contacts
  • Load MCB Indication and Alarm contacts
  • Battery MCB Indication and Alarm contacts
  • Earth Fault Indication and Alarm contacts
  • Reverse Battery Connection Protection
  • Reset Button
  • RS- 232 communication

DC Ripple < 1%
Input and output are protected with MCBs and all settings like boost charge, floating charge and battery charge current can be adjusted via front panel touch pad digitally. DC output is filtered by L/C, so DC ripple at full load always lower than 1% to increase battery life. All rectifiers have standards low-battery and rectifier failure alarm.

Parallel/Serial Connection
The Charger has a modular design to provide service and maintenance simplicity. The outputs of the Battery Chargers can be connected in parallel or in series based on the requirement (N+1).

Technical Specifications

Block Schema
Fully Controlled Thrystor Rectifier Module
GESS DC Chargers are fully isolated since an isolation transformer is placed in between the input and output and because the DC current is controlled by a DC current module. Therefore, the load is always safe even at high input voltage and congested mains conditions. In addition, the failure risk is minimized as semi-conductors are used for the rectifier. Standard L-C filters at the output maintain safe charging of the battery groups.

RS 485 / Modbus communication
Silicon Dropper Module For Load Output (Load voltage output ± 5 %)
Rectifier and Battery Group with the same cabinent
LVD Deep Discharge Battery Protection contactor


Automatic Boost
Automatic boost charge can also be selected on menu. The automatic boost menu has the options for selecting the boost and float current based on battery capacity. Suitable float and boost currents of the battery are set before selecting the automatic boost option. After the set-up, the automatic boost function will monitor the battery current and select boost or float option by referring to the set values. If the charging current is higher than the set boost current, the system will select boost and if the charging current is lower than the set float current the system will select float option. In case of low battery alarm, the automatic boost will select boost option until the battery charging current reaches to the set float value.

Boost Inhibit Function
Boost Inhibit Function is necessarily employed when two DC Chargers with two battery groups operate in a parallel redundant mode. In parallel operation, if two rectifiers start boost-charging at the same time there is danger the load would be damaged by overvoltage. So, the principle idea of Inhibit facility is to block any one of the two chargers feeding the load in Boost mode when the other rectifier is charging the batteries in Boost mode; so the system prevents applying overvoltage to the load. This function is primarily handled by a powerful communication between two rectifiers and the use of contactors.



Battery Charging Characteristics

Ideal and safe charging of batteries is sustained by setting boost and float charge currents. In this way unnecessary boost conditions and deformation of batteries at changing load currents are prevented. Ideal output characteristic via fast microprocessor control.

Battery Test Function


Soft Start Feature

No inrush current at start up

In sudden load changes dynamic response is 300 msec without overshoot or undershoot to secure the load

AC Ripple at full load < 1 %
Battery life is extended significantly via low ripple voltage due to low heat

With this capability rectifier can be used as a power supply even without battery safely with DC Loads

Fully microprocessor controlled rectifier
Thyristor angle is adjusted with load change
½ Load: Phase angle shortened
Full Load: Phase angle at max
Battery test function tests the total battery voltage according to the set program and gives information back to the user. When battery test starts the charging voltage is set to desired test voltage for a period of time and microprocessor analyze the information. If the battery voltage is below the test voltage then Battery Fail Alarm turns ON and charger returns back to float voltage. If the battery voltage is low this event is recorded to event log for future monitoring and service. The test intervals can be set from the front panel and user interface. This function allows the user to monitor the battery status and enhance battery life it with necessary actions.

Remote Monitoring

On both LCD panel and communication interface, all key parameters can be set and real time base events and failures can be tracked. In parallel operation multiple rectifiers can be controlled by the help of same communication interface. The communication is executed via RS232 / RS485 port or Modbus protocols.
Wide Range of Use

DC chargers are ideal for transformer energy distribution centers, gas oil energy distribution centers, natural gas energy distribution centers, mining industry security and lighting, building automation systems and for special telecommunication applications.

The input and output of the charger are protected against improper use and line disturbances electronically. Input and output can be switched by circuit breakers individually. It has self-protection against over temperature. The alarm contacts can be used for external system in the case of any anomaly. The output is fully isolated from the AC line input. The Charger has a modular design to provide service and maintenance simplicity.