The document summarizes a technical seminar presented by Sandesh Pradhan of Aplab Limited on uninterrupted power supply (UPS) systems. Aplab is India's largest private electronics manufacturer. UPS systems provide backup power between the utility network and critical loads to protect against power disturbances. There are two main types of UPS systems - offline UPS briefly interrupt power during outages while online UPS provide constant regulated output without interruption. The seminar discussed UPS principles, components like rectifiers and inverters, and configurations including isolated redundant and distributed parallel setups.

1. Technical Seminar by Sandesh Pradhan (Aplab Limited – Thane )

2. Head Office - Thane

3. ISO 9001 2000 certified company India’s largest private Electronic Equipment manufacturer. Started as R&D Laboratory by Mr. P S Deodhar

4. U ninterrupted P ower S upply ( UPS )

5. UPS is the Mid-Point Between Utility & Critical Load POWER STATION UTILITY NETWORK UPS CRITICAL LOAD

6. Typical Mains Disturbances 3% of failures are related to direct power failures. The rest is mainly due to fluctuations. TRANSIENT Voltage Surge NOISE NOTCHES VOLTAGE DISTORTION MOMENTARY INTERRUPTION LONG-TERM INTERRUPTION FREQUENCY VARIATION SAG SWELL UNDER VOLTAGE OVER VOLTAGE

7. UPS Principle 3 Phase Input Voltage 3 x 415 Vac Frequency 50 Hz 6-pulse thyristor-controlled Optional : 12pulse thyristor-controlled Standard DC Voltages Lead acid Nickel Cadmium 1- or 3-Phase Output Transistorized or IGBT PWM - controlled Inverter POWER IN POWER OUT

8. Rectifier Battery Inverter Bypass SWIN SWMB SWOUT SWBY FROM INPUT DB TO OUTPUT DB UPS BLOCK START PROCEDURE * CHECK SWIN, WSMB, SWBY & SWOUT SWITCHES ARE OFF. * PUT SWOUT, SWBY ON. * WAIT FOR A MINUTE. * PUT SWIN ON. * KEEP SWMB OFF ALWAYS. FOR PUTTING IT ON, REFER MANUAL. STOP PROCEDURE * PUTOFF SWOUT. * PUTOFF SWIN. * PUTOFF SWBY

9. Off - line UPS What is a UPS ? Off-line definition: The UPS is “sleeping” in normal mode At power failures, power will drop out in 5-20 mSec, until the UPS “wakes up”. Input voltage Output voltage critical UPS

10. On-line UPS What is a UPS ? Input voltage Output voltage On-line definition: The UPS is active in normal mode. The UPS is constantly regulating the output voltage without any interruption or variations . UPS

11. Rectifier Battery Inverter Bypass SWMB FROM INPUT DB UPS BLOCK 1 Rectifier Battery Inverter SWMB FROM INPUT DB TO OUTPUT DB UPS BLOCK 2 Static switch Static switch ISOLATED REDUNDANT CONFIGURATION

12. Rectifier Battery Inverter Bypass SWMB FROM INPUT DB UPS BLOCK 1 Rectifier Battery Inverter SWMB FROM INPUT DB TO OUTPUT DB UPS BLOCK 2 Static switch Static switch DISTRIBUTED PARALLEL CONFIGURATION Bypass

13. Rectifier Battery Inverter Bypass SWMB FROM INPUT DB UPS BLOCK 1 Rectifier Battery Inverter FROM INPUT DB TO OUTPUT DB UPS BLOCK 2 Static switch CENTRALISED PARALLEL CONFIGURATION

25. Thanks