neil_m23
New Member
i've college assignment to design OFFLINE UPS. Unfortunately we dont have good guidence at college. I'm also eltrx newbie in design.
Plz Suggest some links. Also guide me step by step how to proceed.
Specifications:
1) 500VA
2) o/p= 230 V quassi-square
3) battery:24V, 7.5A backup time: 30 mins.
(from this we can get VA and AHr. rating of battery)
Features/Indicators:
1) Charging
2) Battery starts trickling
3) overload trip indicator (with time condn, should not trip immediately, wait few seconds)
4)MOSFET f/b isolation (whats this ??? )
3 types of UPS:
1)ONLINE: aka Inverter prefered, In this load is always connected thru UPS system/invetrer (UPS S/w: Normally ON s/w). And Mains s/w is Normally OFF. hence mains is connected only when UPS fails.
Protection Circuit: 1) over vtg and under vtg cutout.
2)overcurrent protection
Advantage of ONLINE: isolation betn load and mains ac supply, henece popular.
2)OFFLINE: aka Line Prefered, Mains s/w: Normally ON and UPS s/w: Normally OFF hence UPS coes into ckt only when Mains supply fails.
changeover time is there abt 5ms or less.
Protection Circuit: 1) mains over vtg
2) o/p overcurrent protection
3) Low battery
3) Line interactive UPS: Similar to offline . schematic is different. battery and charger posn changed.
Plz reply back.
regards,
Neil.
Plz Suggest some links. Also guide me step by step how to proceed.
Specifications:
1) 500VA
2) o/p= 230 V quassi-square
3) battery:24V, 7.5A backup time: 30 mins.
(from this we can get VA and AHr. rating of battery)
Features/Indicators:
1) Charging
2) Battery starts trickling
3) overload trip indicator (with time condn, should not trip immediately, wait few seconds)
4)MOSFET f/b isolation (whats this ??? )
3 types of UPS:
1)ONLINE: aka Inverter prefered, In this load is always connected thru UPS system/invetrer (UPS S/w: Normally ON s/w). And Mains s/w is Normally OFF. hence mains is connected only when UPS fails.
Protection Circuit: 1) over vtg and under vtg cutout.
2)overcurrent protection
Advantage of ONLINE: isolation betn load and mains ac supply, henece popular.
2)OFFLINE: aka Line Prefered, Mains s/w: Normally ON and UPS s/w: Normally OFF hence UPS coes into ckt only when Mains supply fails.
changeover time is there abt 5ms or less.
Protection Circuit: 1) mains over vtg
2) o/p overcurrent protection
3) Low battery
3) Line interactive UPS: Similar to offline . schematic is different. battery and charger posn changed.
Plz reply back.
regards,
Neil.
