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Chapter 5 - installing input power wiring, Installing transformers and reactors (optional), Hapter – Rockwell Automation GV3000/SE AC Bookshelf Drive Hardware Ref, Installation, and Troubleshooting User Manual

Page 45: Installing input power wiring, 1 installing transformers and reactors (optional)

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Installing Input Power Wiring

5-1

C

HAPTER

5

Installing Input Power Wiring

This chapter describes incoming line components and how to install them.

5.1 Installing Transformers and Reactors (Optional)

Input isolation transformers might be needed to help eliminate the following:

Damaging line voltage transients from reaching the drive.

Line noise from the drive back to the incoming power source.

Damaging currents that could develop if a point inside the drive becomes grounded.

Observe the following guidelines when installing an isolation transformer:

A power disconnecting device must be installed between the power line and the
primary of the transformer.

If the power disconnecting device is a circuit breaker, the circuit breaker trip rating
must be coordinated with the in-rush current (10 to 12 times full load current) of the

transformer.

For drives equipped with an AC Mains Filter, an input isolation transformer rated
more than 1000 KVA for 460 VAC with less than 5% impedance should NOT be

used directly ahead of the drive without additional impedance between the drive and

the transformer.

For drives not equipped with an AC Mains Filter, an input isolation transformer rated
more than 315 KVA for 460 VAC with less than 5% impedance should NOT be used

directly ahead of the drive without additional impedance between the drive and the

transformer.

For drives equipped with an AC Mains Filter, the maximum AC line distribution system

capacity is 1000 KVA, three-phase with 30,000 amps symmetrical fault current

capacity with a line impedance of less than 5%.

!

ATTENTION: Distribution system capacity above the maximum

recommended system KVA (1000 KVA for 460 VAC for drives equipped

with an AC Mains Filter, 315 KVA for 460 VAC for drives not equipped

with an AC Mains Filter) requires the use of an isolation transformer, a

line reactor, or other means of adding similar impedance to the drive

power input. Failure to observe these precautions could result in damage

to, or destruction of, the equipment.
ATTENTION: When the AC line is shared directly with other

SCR-rectified drives, an optional snubber resistor braking kit might be

required to alleviate excess DC bus voltage. Failure to observe these

precautions could result in damage to, or destruction of, the equipment.