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EMI strain relief clamps/backshells for shield motor cable?

this is how we are accustomed to doing it . . . just a hose clamp.
9F5558CC-33DA-4D2A-B7B0-36F8098E3369.jpg

If you are thinking a strain relief through an enclosure, then the unit you linked works if you cut the insulation off and expose the shield.

We use units like this . . .
0EDC6CE6-C286-411E-9AB8-702B52E640FE.jpg
 
If you are thinking a strain relief through an enclosure, then the unit you linked works if you cut the insulation off and expose the shield.

We use units like this . . .
View attachment 262496

I have these in stock. The drive has a metal shield with a punched out hole plug. The hole is 1". The diameter of the thread is .880. I could make a couple of washers with the smaller hole size. But the unit in the picture has a very short thread length. Making a 1" coin and tacking it in the hole and then drilling a smaller hole is one idea.
 
The cable fitting should be selected for the cable type used. The Digikey item you listed is a cord grip fitting. For attaching the shield you should follow the recommendations of the VFD manufacturer.

If we are to discuss as a general rule how to connect the shield, the shield wire should be used with a connector listed (UL) for use with the shield wire type. For purposes of electrical noise reduction only one end of the shield should be connected, at the single point source of ground which in this case is the VFD grounding terminal.
 
The cable fitting should be selected for the cable type used. The Digikey item you listed is a cord grip fitting. For attaching the shield you should follow the recommendations of the VFD manufacturer.

Well the manual just says which plug hole to use for the motor cable, power, and control. Does not specify a connector.

If we are to discuss as a general rule how to connect the shield, the shield wire should be used with a connector listed (UL) for use with the shield wire type. For purposes of electrical noise reduction only one end of the shield should be connected, at the single point source of ground which in this case is the VFD grounding terminal.

Motor cables are grounded at source and destination.
Control and communication cables are grounded at the source only, not at the drive.
According to Allen Bradley.
 
The cable fitting should be selected for the cable type used. The Digikey item you listed is a cord grip fitting. For attaching the shield you should follow the recommendations of the VFD manufacturer.

If we are to discuss as a general rule how to connect the shield, the shield wire should be used with a connector listed (UL) for use with the shield wire type. For purposes of electrical noise reduction only one end of the shield should be connected, at the single point source of ground which in this case is the VFD grounding terminal.

Shielding for noise immunity should be landed at one end only - this is typically for low level signals that you want to protect from being corrupted by EMI / EMF sources.

However, shielding for EMI/EMF noise suppression (especially with inverter synthesized sinewave wave forms) is a completely different topic and you will find that EMC guidelines suggest landing of shield where it enters the cabinet and also at the drive and also at the motor. The linked cord grip is one such shield landing point designed specifically for this application when entering an electrical enclosure.
 
However, shielding for EMI/EMF noise suppression (especially with inverter synthesized sinewave wave forms) is a completely different topic and you will find that EMC guidelines suggest landing of shield where it enters the cabinet and also at the drive and also at the motor. The linked cord grip is one such shield landing point designed specifically for this application when entering an electrical enclosure.

That was what I am threading about on.

Ground cable at electrical enclosure, drive metal frame, or both.
I was not planning on striping the cable to expose the shield to make contact at the VFD enclosure entry hole. I was thinking about using a rubber grommet for the enclosure hole and then connect the cable shield to the VFD frame. So this is wrong?
 
Recommendations vary, also sometimes a non-metalic enclosure may be used so one cannot use a strain relief shield ground. I typically use a star ground or grounding bar attached to the metal back plane. The motor cable end I ground the shield to the motor ground, depends on the type of VFD cable used. At the VFD I bond the motor ground/shield to the back plate ground. I bond the low voltage control wire shield to the VFD ground screw, the other shield end is not grounded. Sometimes use ferrite rings on the input VFD power and motor cable just as it exits the VFD. There are different toroid types/materials, I use Fair-Rite 75 (broad band) Ferrite Toroids. Do not pass the ground through the ring, wind each leg equally staggered in the same direction. Otherwise there are also clamp on types.
 
As stated by others, for vfd installation the shield must be well bonded at both ends (drive and motor). The correct bushing for the cable should be used. The best VFD cable hands down that I know of is the Service Wire Service Drive cable with matching connectors.

Cable:
ServiceDrive VFD Cable (Tray) - 2kV

Connector:
ServiceDrive VFD Cable Connector (Armored)

I am a bit biased as I had a significant hand in design of the cable/connectors......

There 3 types of stray currents caused by a VFD.

1. Circulating currents - not too worried in the 10 to 25 hp range - solution is to insulate opposite drive end bearing
2. Stator to rotor capacitance current flow - can affect all motor sizes - solution is a drive end ground brush
3. The most damaging one to all size motors is stator to frame capacitance currents. Solution is a properly bonded shielded motor lead cable. Not only does it prevent the stray currents from leaving the drive/motor/cable system, it also prevent cross talk.

Bond both ends of the shield well to the drive backplane and to the motor frame. Use high frequency braid if you don't have bushings that do the job. The Service Drive cable bonds the shield with the connector and also with secondary high frequency braids.
 








 
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