Pre wired 3/8 Greenfield aka BX cable

hvaclover

I have been using BX to wire in replacement furnace power for years. (Local code always to run a new line from existing wire in a J box to furnace).

Two things I want to get some help on: BX connectors. For some reason straight BX connectors just don't fit. The BX is actually much smaller than 3/8 greenfield. The box of fitting says BX connectors on it but the connector set screw barely makes the straight connector snug.
What is it I am missing here?


Also I found one certain brand Of BX (pre-wired Greenfield) the conductors were copper clad aluminum . On these jobs I have returned five years later to find the neutral connection inside furnace J-boxs to have over heated and melted the wire nut. Why would it not burn out the supply side connection of the incoming power?

I have been using 12-3 if it matters. i have gone back to threading 12-3 thru Greenfield until I can sort out if it's me or the electrical supply just hasn't given me the right connectors. Big box stores the same. Their BX connectors are too large also.

__________________
Just slow, not stupid.

hvaclover

What? Not specific enough?

__________________
Just slow, not stupid.

InPhase277

Use the BX connectors that look like romex connectors. They have a clamp that should allow you to use any size up to 3/8".

hvaclover

Ok i think i know what you mean We call them squeeze connectors. We use them to secure low voltage wiring into the side of ac's that dont provide a rubber bushing to prevent wire chafing on bare metal.

__________________
Just slow, not stupid.