Installation/Wiring 1-7
RFI Filter Grounding
Using an external filter with any drive rating, may result in relatively 
high ground leakage currents. Therefore, the filter must only be used in 
installations with grounded AC supply systems and be permanently 
installed and solidly grounded (bonded) to the building power 
distribution ground. Ensure that the incoming supply neutral is solidly 
connected (bonded) to the same building power distribution ground. 
Grounding must not rely on flexible cables and should not include any 
form of plug or socket that would permit inadvertent disconnection. 
Some local codes may require redundant ground connections. The 
integrity of all connections should be periodically checked.
The PowerFlex 40P does not provide branch short circuit protection. 
This product should be installed with either input fuses or an input 
circuit breaker. National and local industrial safety regulations and/or 
electrical codes may determine additional requirements for these 
installations. 
Fusing
The ratings in the table that follows are the recommended values for use 
with each drive rating. The devices listed in this table are provided to 
serve as a guide.
Bulletin 140M (Self-Protected Combination Controller)/UL489 
Circuit Breakers
When using Bulletin 140M or UL489 rated circuit breakers, the 
guidelines listed below must be followed in order to meet the NEC 
requirements for branch circuit protection.
• Bulletin 140M can be used in single and group motor applications.
• Bulletin 140M can be used up stream from the drive without the 
need for fuses.
Fuses and Circuit Breakers