Regarding the UPS switching issue
Thread Content
Under normal conditions, a UPS is powered by mains electricity (the operating power source); after rectification and inversion, it supplies power to the DCS or other critical loads, while the battery remains in a floating charge state. Under what conditions will the UPS switch to static bypass? Under what circumstances is it powered by a battery? Under what circumstances is it switched to manual maintenance bypass?
When the mains power is normal, the UPS operates in static bypass mode; when the mains power fails, the UPS relies on its batteries for power. If there are other circuits available to supply power to the DCS in addition to the UPS, the UPS can be switched to manual maintenance mode.
This post was last edited by zyz8438 on 2010-10-2 21:31. Haha, it doesn’t seem right. Under normal conditions, the UPS output is provided by the inverter unit; it only switches to the static bypass when the inverter unit fails!
Will the UPS switch to static bypass? Under what circumstances is it powered by a battery? Under what circumstances is it switched to manual maintenance bypass? Standard answer: lol: 1. The system will switch to static bypass in the following two situations; at the same time, the status of manual maintenance bypass is also indicated: (1) When the load is overloaded, short-circuited (which can essentially be considered a severe form of overload), or when there is a fault with the inverter, in order to ensure continuous power supply to the load, the static bypass switch activates, allowing direct power supply from the mains to the load. (2) During maintenance or testing, for safe operation, the maintenance bypass switch is closed to supply power directly to the load from the mains electricity. Isolate the UPS system; this switching mechanism ensures uninterrupted power supply to the load during UPS maintenance or testing. 2. Battery power status: When the mains power is cut off, or when the voltage or frequency of the incoming mains power exceeds the allowed range, the rectifier shuts down automatically. At this time, the direct current supplied by the battery pack is converted into pure alternating current by an inverter and supplied to the load.
The answer upstairs is completely correct! 1. When the mains power is abnormal or even interrupted, the UPS will not switch to the static bypass. Instead, it is powered by a battery, with alternating current being outputted externally through an inverter. In this way, complete disturbance-free operation can be achieved. Before the battery is discharged to a certain extent, if the mains power returns to normal, the UPS will switch back to being powered by the mains without any disruption, and the battery will once again enter float charging mode. If the battery is discharged to a certain level and the mains power still does not return, the UPS will switch to static bypass mode. 2. If there is an overload (including a short circuit) or a fault in the inverter itself, the UPS will switch directly to static bypass mode. The switching time of the static bypass is in the millisecond range, and the power-off time is also in the millisecond range; thus, it has no impact on the load. However, there is still a difference compared to the completely disturbance-free and power-loss-free period when switching to battery power as specified in Article 1. 3. The manual maintenance bypass is a measure taken to isolate the UPS for safety reasons, only when the UPS is under maintenance or testing.
It seems that the people on the 2nd floor don’t understand what a static bypass is; a static bypass does not refer to the bypass on the UPS unit, but rather to an external bypass power supply for the UPS.
Reply to 7# gfj870823: The static bypass should be integrated inside the UPS, right? The maintenance bypass should be outside the UPS!
It is divided into online and offline types, with different wiring as well.