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Rockwell Automation Publication 750-IN118A-EN-P - May 2021
Chapter 4 Power Wiring
Intermittent Overload
Each PowerFlex 755T Drives Configured to Order Program product is designed
and sized based on a duty rating that the customer selects based on the
application. The duty rating of the drive must be set as specified on the
schematics and data nameplate.
Motor Overload Protection
PowerFlex 755T Drives Configured to Order Program products have the
following motor overload protection.
Short-circuit Current Rating
This section covers short-circuit current rating for the PowerFlex 755T Drives
Configured to Order Program product, based on input protection devices in a
configured input bay. If there is no configured input bay, or there is a control-
only configured input bay (has no input protection devices), then the short-
circuit current rating information for the product is the same as the short
circuit current rating information for the standard drive. That information is
provided in the PowerFlex 750-Series Products with TotalFORCE Control
Installation Instructions, publication
.
Applying and Removing
Power
When applying and removing power from your drive, be aware of the
following precaution.
Contactor Precautions
Follow these precautions when using input contactors, output contactors, or
bypass contactors with PowerFlex 755T Drives Configured to Order Program
products.
Input Contactor Precautions
If you supply an input contactor upstream from a configured input bay, the
following precautions apply.
Electronic motor
overload protection
Class 10 motor overload protection according to NEC article 430 and motor over-
temperature protection according to NEC article 430.126 (A)(2). UL61800-5-1 File E59272.
Maximum short-circuit current rating Suitable for use on a circuit capable of delivering not more than 100 kA rms symmetrical amperes, up to 600V maximum and 65
kA rms symmetrical amperes at 690V maximum.
Actual short-circuit current rating
May be further limited by AIC rating of customer supplied branch circuit short-circuit protection device (fuse or circuit breaker).
The lowest rated device in the circuit determines the branch short-circuit rating. If the protection device providing power to the
drive is rated lower than 100 kA rms, the branch short-circuit protection is the short-circuit rating of the protection device. If the
protection device has a rating higher than 100 kA rms, the branch circuit protection is 100 kA rms for voltages up to 600V and
65kA for 690V. For branch circuit short-circuit protection fuse and circuit breaker ratings, see
and
Input Power Circuit Breakers on page 105
.
ATTENTION:
We recommend that you wait 5 minutes before cycling power
disconnect switches. This recommendation applies to both Off-to-On and On-
to-Off transitions. Rapid power cycling can result in equipment damage.
If your PowerFlex 755T Drives Configured to Order Program product includes a
configured input bay with circuit breaker input protection, then you can
disconnect power to the drive by using the circuit breaker instead of a customer-
supplied input contactor.
