Grounding a BX wire connection to new dishwasher

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Old 07-07-13, 07:42 PM
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Grounding a BX wire connection to new dishwasher

I am in the process of installing a new dishwasher however we seem to have BX cable running to the appliance. There is what appears to be a ground wire in the metal sheathing that has been cut very short but the previous owner did not have any ground wire going to the dishwasher box.

Do I need to trim the sheathing to expose a sufficient amount of ground wire? Alternately, I've read there is a clamp that can be used to connect BX wire to modern appliances with three wire connections. Or is there some alternate way to ensure that the dishwasher is safely grounded?

Thanks.
 
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Old 07-07-13, 09:08 PM
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No, With BX like you describe, the metal jacket is your ground. You can confirm this by taking a meter and checking between the hot wire and the metal jacket. You should get 120 volts. You need to use a proper connector for A/C cable (the NEC name of BX) The connection plate of the dishwasher should also be metal to carry the ground.
 
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Old 07-08-13, 01:46 PM
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Make sure the ground wire from the dishwasher is connected to the metal box where you are connecting the BX. Use a proper cable clamp as Toylyn has already suggested, and make sure you have a red hat in there while you are at it.
 
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Old 07-08-13, 02:30 PM
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Type AC cable, commonly called BX, does not have a grounding conductor. If what you are describing is a thin uninsulated wire, commonly aluminum, it is the bond conductor. You don't need to do anything with it.
 
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Old 07-08-13, 03:16 PM
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There is what appears to be a ground wire in the metal sheathing that has been cut very short but the previous owner did not have any ground wire going to the dishwasher box.

Do I need to trim the sheathing to expose a sufficient amount of ground wire?
If you have Type MC cable, which has a ground wire, then yes.

Both MC and AC are often referred to as BX. PCboss is right: the true descendant of BX is AC, which doesn't contain a grounding conductor.
 

Last edited by Nashkat1; 07-08-13 at 03:37 PM.
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Old 07-08-13, 08:02 PM
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What is the proper connector to secure the cable to the dishwasher? Videos I've seen described it just as a 'metal nut' that attaches the cable to the box but they didn't actually show how the connection worked.

Thanks for all the help.
 
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Old 07-08-13, 08:11 PM
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You use an armored cable connector. Example: https://www.foxelectricsupply.com/co...oductNo=ARL845
 
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Old 07-08-13, 08:35 PM
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Here are some AC and or MC connectors.

Flex • AC • MC Fittings
 
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