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UPS Power Inputs

UPS Power Inputs

UPS Power Inputs

(OP)
Why the bypass transformer input is fed from Normal low voltage power supply and the rectifier transformer is fed from Emergency low voltage power supply? If so, how the outputs are synchronized?

RE: UPS Power Inputs

Because UPS operates in Emergency Condition practically speaking. Bypass takes place when UPS has internal failure. And then when one of the mode is operational either grid supply or double conversion UPS supply then where is the question of synchronization of output?

RE: UPS Power Inputs

Usually they are not. It's either one supply or another, but "normal" supply is fed through the UPS.

The bypass is just there in the event that the UPS dies or needs some maintenance.

Depends on your UPS - Some have the output synchronised with the input, if the input voltage is there, some don't. RTFM.

But a circuit diagram would help.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: UPS Power Inputs

@Little Inch You mean synchronization just to allow a zero break transfer from UPS to Mains right?

RE: UPS Power Inputs

(OP)

Quote (LittleInch)

But a circuit diagram would help.

RE: UPS Power Inputs

NickParker,
Usually,
1) The Rectifier line is connected to the stabilized power supply which is called the NORMAL power so that UPS gives out a "CONDITIONED" power to the connected load.
2) The by-pass line is connected to a secondary source (with expected interruptions) so that whenever the UPS is in trouble (INV failure) it jumps over to the by-pass line
which gives an "UNCONDITIONED POWER" to the connected load until the Rectifier/ Inv line is re-stored.

RE: UPS Power Inputs

I'm no electrical engineer, but the key would seem to be in that curious box at the end where the two contacts are NC. This would appear to provide seamless transfer of the load from the bypass transformer to the UPS.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: UPS Power Inputs

That looks like more than a simple UPS.
It looks like a UPS with a maintenance bypass and a fast transfer bypass.
In the event of a total failure, the UPS will use the inverter to produce an output from the batteries.
In the event of a failure of the Emergency Switchboard, but with normal power still available, the device will do a fast transfer and bypass to the Vessel Switchboard, and save the battery energy.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

RE: UPS Power Inputs

The UPS output/inverter should synchronize to the internal/external bypass source when it is present. The internal/external bypass feeds must be from the same source. I don't know why the bypass would not be also coming from the emergency source.

RE: UPS Power Inputs

If the bypass came from the emergency panel then you couldn't maintain service by going to bypass if you needed to service the emergency panel.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

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