Bonding wire in VFD shielded cable use as EGC

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marcosgue

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Tampa
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Electrician
This's a new construction aquarium and the majority of motor for pump are 480V,3Ph feeding from the mcc to disconnect adjacent to the motor. For feeding the motor we're using 3M vfd cable shielding that come with kit termination each, the cable come with 3 conductor no egc. Is allow to use the drain wire inside the cable shielded as EGC to the motor instead to use the egc and sizing according to Table 122?
 
In my opinion the cable should be 3 wires+egc, but I'd like to hear some opinion with the use of this type of cable because this the first time that we use it.
Thanks and I appreciate any input would help
 
Thanks all this's the best Electrical Forum to learn. Bless you all and have a nice day all
 
marcosgue said:
This's a new construction aquarium and the majority of motor for pump are 480V,3Ph feeding from the mcc to disconnect adjacent to the motor. For feeding the motor we're using 3M vfd cable shielding that come with kit termination each, the cable come with 3 conductor no egc. Is allow to use the drain wire inside the cable shielded as EGC to the motor instead to use the egc and sizing according to Table 122?
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Was told to only ground a shield at one end. If you ground it bond it at both ends it could carry a current that could cause problems. The 5 Millon campus that I retired from had over 500 VFD'S from 2 to 1,750 HP and none had the shielded cable. Every drive was in EMT and a copper ground wire to pecker head. Some were used to on old 1970 era plain Jane NEMA motors and we seldom list a motor. Even when they updated some of the 45 year old elevators from DC motors to AC motors & VFD'S they never used the shielded cable. I asked tech guys from two different drive companies what their opinion was and they said it was a waste of money. Rather spend money on quality reactors on drives.
 
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