is microprocessor device for charging, fast charging by PARS method, discharging and maintenance of industrial (traction) or stationary lead-acid batteries with nominal voltage of 48V with maximum charge current of 250A. It is developed as a consequence of need for fast charging, easy for use, safe, reliable and fully controllable and relatively cheep device for servicing and maintenance of industrial batteries. GBC-PARS has 16 three-phase chargers in same box. Those sixteen charging modules are controlled by main microprocessor. Those chargers are high frequency half-bridge constant voltage chargers with current limit. That means that current reaches output voltage on connected battery, which is limited. After reaching desired voltage, that voltage level is maintaining constant and charge current drops as battery is charging. Modules are fitted in common aluminium-steel box on wheels with central control unit, protection devices, and keyboard and display unit. Charge current (current limit) is selected as function of nominal battery capacity, or in function of desired charging time and capacity. Also, charging voltage is settable as charging voltage per one cell (multiplies with 24 cells). Voltage, current, duration and capacity (Ah) are controlled and many precaution measures are implemented. Because of discharge capability, battery RESET operation is possible (constant current discharge, break voltage 42V 1.75V/Cell). Also, GBC-PARS has MAINTENANCE operation (constant voltage charge 57.6V).

As device is microprocessor, with measuring current, voltage, duration, Ah, temperature of heat sink of semiconductor parts, it is possible to implement different algorithms. It is possible to change voltage and current limits, conditioning of charge characteristic, pausing, waiting for event (measuring Ah during charge), conditioning end of charging (duration, Ah...), connection with PC computer, analyse and printing charge graphs etc.

Energy circuit is made of input filter with high quality electrolytic capacitors (EPCOS-SIEMENS 105C), high-frequency transformer (ETD Siemens) and mosfet half-bridge (International Rectifier IR), ultra fast diodes, and inductance and PWM modulator. Working frequency is 30kHz.

Thanks to voltage limit, it is possible to charge without surveillance, because there is not over charge (over night or during weekend). As well, in a case of main power failure during charge, after it’s returning device automatically continues charging with parameters, which were previously set (before power failure). LCD display with 2x16 characters shows values of current, voltage, time, capacity, device status, warnings, alarms etc. There are more than 10 menus for setting the parameters of charging. Device is placed in red plasticified aluminium-steel box on wheels. Main switch, three pole automatic fuse and signal lamps, start (scroll) and stop (select) buttons, switch R/S (Ready/Set), led diodes, LCD display for indication and connector for communication with PC computer and indication lamps are placed on the devices front panel. Charge cables, power supply cable and cable holders are on the back panel of device.

With software GCDTS v1.01 it is possible to connect device with PC computer via RS232 serial port. Software gives opportunity of showing charge and discharge graphs in real time, possibility of reading charge and discharge data in case that device wasn’t connected with PC, printing and storing the results, creating reports etc.

Gaus Battery Charger GBC48V250A-PARS has following protections:

1. no sparks during connecting or disconnecting plugs from battery in charge operation;
2. forced air cooling;
3. control of a minimum of allowed connected battery voltage (forbidden start for voltages less than 20V);
4. temperature protection on heat-sink of semiconductor energy components;
5. in case of main power failure, after its restoring, charging automatically continues with earlier set parameters;
6. Slow three-pole automatic fuse in AC circuit;
7. slow fuse 315A in DC circuit;
8. soft start of PWM modulator;
9. soft start in charging input electrolytic capacitance;
10. short circuit protection (if detected current is more than 275A charger is automatically turned off);
11. over voltage protection (>72V);
12. protection from plugs (cables) falling during charge (freezing device until solving of problem);
13. Reverse polarity protection with forbidden start.

• Type of voltage converter: 3x mono-phase half-bridge DC-DC converter;
• Supply 3x400V +/- 10%, 50Hz 3x6 kW; max. output power 16kW;
• Nominal input current: 3x26A; maximal start current: 3x30A
• Instruments: LCD display 2x16 characters, ampermeter 0-999A, voltmeter 0-99.99V, temp1 –99º- 99ºC
• Cables with Pb plugs: l=3m, S=75mm2
• Ambient temperature: 0 do +40ºC

• EN60335-1/194 (Safety of household and similar electrical appliances-Part 1: General requirements); SIST EN 60335-1, May 1998; JUS IEC 60335-1 1998. and
• EN60335-2-29 (Part 2: Particular requirements for battery chargers); JUS IEC 60335-2-29 year 2000.