UPS power supply issue
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This post was last edited by ggwwhh on 2020-7-15 at 10:49. The design specifications for power supply in petrochemical instrumentation state that a UPS requires two power sources: one primary source and one bypass source. The primary source is used to supply power to critical electrical loads; so what are the requirements for the bypass source in terms of electrical functionality?
A backup power supply is generally used to provide power to equipment in the event of a failure of the main power supply, and its requirements should be identical to those of the main power supply. Let’s learn together*; please correct any mistakes.
Is this bypass a maintenance bypass? The maintenance bypass is usually built into the UPS; it allows the UPS to automatically switch to bypass power supply in case of failures such as sudden damage to the inverter inside the UPS. The bypass generally only has a voltage stabilization function – it provides the same power supply, but it no longer passes through the batteries.
It is recommended that the bypass power supply and the main power supply not share the same transformer.
In my understanding, the meaning of dual-power supply for UPS is that there are separate transformer outputs and different circuits in the low-voltage cabinets, so that partial power outages during maintenance do not affect the UPS power supply. Just like in normal situations, the power supply for the control system comes from the mains (bypass); when the mains power is lost, a UPS takes over as a backup
1. It is best to come from different low-voltage busbars. 2. The power supply passes through an isolation transformer before serving as the input for the UPS.
A bypass power supply is another power source. Generally, it has dual backup power supplies.