Plastic box with LFMC

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wireday

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New England
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Master electrician
I am running a GEC, I have EMT to LFMC to a plastic box manual starter. From the plastic manual starter goes to 1/2 HP 120Volt motor, Do I need to bond the LFMC? I will have a GEC,
 
I think you mean an EGC and yes you will need to bond the LFMC.
 
All metal parts associated with the electrical system should be bonded. There is an exception, I believe, for an underground metal elbow in a plastic conduit run.
 
I would be bonded at the EMT connection and at the motor through the EGC, just not at both ends of the LFMC
 
wireday said:
I was asking to know if I only need to bond only one end of LFMC
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In general nonmetallic boxes are only permitted with nonmetallic raceway and cable unless you meet either of the two exceptions in 314.3.
 
Dennis Alwon said:
Yes only one end is needed.
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The way I read 314.3 Exception you need to bond each metal raceway that enters a nonmetallic box, regardless if its bonded by the EMT at the other end.

Code: 
314.3 Nonmetallic Boxes. Nonmetallic boxes shall be permit-
ted only with open wiring on insulators, concealed knob-and-tube
wiring, cabled wiring methods with entirely nonmetallic sheaths,
flexible cords, and nonmetallic raceways.

Exception No. 1: Where internal bonding means are provided
between all entries, nonmetallic boxes shall be permitted to be
used with metal raceways or metal-armored cables.
 
I read the exception to be used when there is more than one raceway in the non metallic box. This is to provide bonding for all the other metal raceways that are not connected to a ground.
 
Dennis Alwon said:
I read the exception to be used when there is more than one raceway in the non metallic box. This is to provide bonding for all the other metal raceways that are not connected to a ground.
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The way i read the only other exception #2 is for plastic boxes with a bonding means built in, so by your reading of exception #1 it implies you can't use a plastic box with just one metal raceway (unless it has the bonding means built in per exception #2).
wireday said:
I am running a GEC, I have EMT to LFMC to a plastic box manual starter. From the plastic manual starter goes to 1/2 HP 120Volt motor, Do I need to bond the LFMC? I will have a GEC,
Click to expand...
I'd say whenever you have a metal raceway or cable hitting a plastic box you need a grounding bushing, wedge or hub, unless the box has a "
integral bonding means with a provision for attaching an equipment bonding jumper inside the box" and its " provided between all threaded entries in nonmetallic boxes listed for the purpose"
 
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