Description

SPECIFICATION:

Based on highly reiable Microchip PIC micro ® microcontroller.
MOSFET based power stage, with PWM AC output.
Mains to Backup mode changeover time less than 9mSec.
Backup mode protected against Overload, short circuit, reverse phase and unbalanced MOSFET drive.
Line Synchronized change over from Mains to Backup and Back.
Over current of MOSFET’s protected within micro seconds.
Three step AVR with input range 140V to 280V AC. and output range 200-245V AC.
MOSFET based PWM battery charger.
Automatic low battery warning and cut off.
Maximum output load = 600VA Test Points & Observations:
Test Point 1 – AC mains voltage at the input of UPS.
Test Point 2 – AVR first relay control signal.
Test Point 3 – AVR second relay control signal.
Test Point 4 – AVR third relay control signal.
Test Point 5 – Transformer bindings for AVR section.
Test Point 6 – Transformer bindings for PWM section.
Test Point 7 – Transformer bindings for charging section.
Test Point 8 – AC voltage at the output of UPS.
Test Point 9 – Output voltage of charger (MAINS MODE) & Battery voltage (BACK UP MODE) Test Point 10 – PWM 1 Signal from PIC controller.
Test Point 11 – PWM 2 Signal from PIC controller.
Test Point 12 – Control signal of buzzer from PIC controller.
Test Point 13 – Inverter indicator signal.
Test Point 14 – Output indicator signal.
Test Point 15 – Mains indicator signal.
Test Point 16 – Battery reference voltage input to PIC controller