dryer 3 prong

Status
Not open for further replies.
For installations prior to the 1996 NEC (250-60 changed to "existing branch-circuit installations only") using a 3 conductor SE cable with the neutral also serving as the EGC was permitted for clothes dryers when a number of conditions were met
 
infinity said:
For installations prior to the 1996 NEC (250-60 changed to "existing branch-circuit installations only") using a 3 conductor SE cable with the neutral also serving as the EGC was permitted for clothes dryers when a number of conditions were met
Click to expand...
That is correct. It was moved and is now listed under this section (I high-lighted some of the important language in bold text) :

250.140 Frames of Ranges and Clothes Dryers.
Frames of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction boxes
that are part of the circuit for these appliances shall be
connected to the equipment grounding conductor in the
manner specified by 250.134 or 250.138.

Exception: For existing branch-circuit installations only
where an equipment grounding conductor is not present in
the outlet or junction box, the frames of electric ranges,
wall-mounted ovens, counter-mounted cooking units,
clothes dryers, and outlet or junction boxes that are part of
the circuit for these appliances shall be permitted to be
connected to the grounded circuit conductor if ALL the following
conditions are met.

(1) The supply circuit is 120/240-volt, single-phase, 3-wire;
or 208Y/120-volt derived from a 3-phase, 4-wire, wye-connected
system.
(2) The grounded conductor is not smaller than 10 AWG
copper or 8 AWG aluminum.
(3) The grounded conductor is insulated, or the grounded
conductor is uninsulated and part of a Type SE service entrance
cable and the branch circuit originates at the
service equipment.
(4) Grounding contacts of receptacles furnished as part of
the equipment are bonded to the equipment.
 
Ok, don't hate me for this...but why does it matter when?

It's the rule now. What difference does it make when it became a rule? According to the answers it's been a couple decades.

So why do you ask, OP?
 
iwire said:
It is my understanding that it was never NEC compliant to run a a 3 wire of any type from a sub panel to a range or dryer.
Click to expand...

When I first moved here my boss surmised that since se cable was allowed (3 wire) then it was okay to run NM. We ended up running 10/2 nm to a dryer from a sub panel. The world didn't end and no one has dies yet but boy did we do some BS work back then. I didn't know any better and did what he asked. :happyno:
 
Dennis Alwon said:
When I first moved here my boss surmised that since se cable was allowed (3 wire) then it was okay to run NM. We ended up running 10/2 nm to a dryer from a sub panel. The world didn't end and no one has dies yet but boy did we do some BS work back then. I didn't know any better and did what he asked. :happyno:
Click to expand...

I remember running 10/2 to many dryers, I was doing tons of multi unit condos in Boston at that time.

The boss would have us run 4 wire SER (3 insulated, 1 bare) to ranges but then he would buy 3 wire receptacles and range cords for us to install. When I asked why we ran a four wire cable but installed 3 wire cords his response was 'if we get caught on it we would not have to rip open drywall to change the cable'. :( :roll:

Being 18-20 at the time, making great money and really only caring about the next chance to party I was fine with it. It was not till I was close to 30 before I really took an interest in being a professional.
 
iwire said:
It is my understanding that it was never NEC compliant to run a a 3 wire of any type from a sub panel to a range or dryer.

I know it was done, I did it myself back in the early 80s but that was just lack of enforcement.
Click to expand...
I was pretty sure if you had an insulated neutral you were good, just couldn't use SE from a sub panel.

Much like you, it was what we all did and I just did what I was told.
 
When Moses came down off Sinai, which version of NEC was a sub paragraph of which commandment?
 
iwire said:
I remember running 10/2 to many dryers, I was doing tons of multi unit condos in Boston at that time.

The boss would have us run 4 wire SER (3 insulated, 1 bare) to ranges but then he would buy 3 wire receptacles and range cords for us to install. When I asked why we ran a four wire cable but installed 3 wire cords his response was 'if we get caught on it we would not have to rip open drywall to change the cable'. :( :roll:

Being 18-20 at the time, making great money and really only caring about the next chance to party I was fine with it. It was not till I was close to 30 before I really took an interest in being a professional.
Click to expand...


Golly at least my boss thought it was compliant...:D
 
Status
Not open for further replies.
Top