EQUIPMENT Ground as a Neutral

[brother]

Well, this is mostly to vent. Been working on alot of kitchen equipment lately, and I know the NEC doesnt govern the manufacturers, but it just bugs me when they use the 'egc' as the neutral. Basically, they need a 120/208 4 wire receptacle, (2 hots 1 neutral 1 ground) but they only specify 208 (2 hots and 1 ground).

Internally they use the ground to carry the current for their 120 volt parts. (ie electronic boards etc). Once in a while Ill run into one that has a control transformer in it. but too many times I see where they bond to the ground their circuits.

We have to seperate grounds and neutrals on the load side of the panel, Why is it not enough pressure to make the manufacturers do the same and seperate them??? is there less danger in their eyes??

 

[gndrod]

Cooks Unite...

Cooks Unite...

but they only specify 208 (2 hots and 1 ground).

Internally they use the ground to carry the current for their 120 volt parts. (ie electronic boards etc). Once in a while Ill run into one that has a control transformer in it. but too many times I see where they bond to the ground their circuits.

Why is it not enough pressure to make the manufacturers do the same and seperate them??? is there less danger in their eyes??

I agree. The control board Low Voltage cop-out is usually pulled out of a hat just like the politicians are doing in Congress on healthcare now. What can we do about it?...write to your Congressman (CMP)..... rbj

 

[Smart $]

I agree. The control board Low Voltage cop-out is usually pulled out of a hat just like the politicians are doing in Congress on healthcare now. What can we do about it?...write to your Congressman (CMP)..... rbj

I can just see the look on my congressmen's faces when I write to them about the use of grounding path for neutral current...

Of course some kind of result is better than what I'm getting on healthcare issues...

 

[e57]

Most are shipped for the 'old way', and have conversion instructions adding a 4-wire cord. It's been years since the change (93 I think?), but they still think all this equipment is going ito old building and that they are doing the purchaser a 'favor'.

 

[brother]

Most are shipped for the 'old way', and have conversion instructions adding a 4-wire cord. It's been years since the change (93 I think?), but they still think all this equipment is going ito old building and that they are doing the purchaser a 'favor'.

Well, it just seems like most of the new stuff I see do NOT have the option to wire it differently. Maybe Im in the wrong biz, I should be a manufacturer of something, because you can make alot of money and get away with alot.

 

[augie47]

I
Of course some kind of result is better than what I'm getting on healthcare issues...

amen to that !

I'm amazed I still see ranges that have 4 wired cords but the neutral bonded at the range. Seems SOP for "big box store" installs.

 

[e57]

Well, it just seems like most of the new stuff I see do NOT have the option to wire it differently. Maybe Im in the wrong biz, I should be a manufacturer of something, because you can make alot of money and get away with alot.

Maybe you didn't look, or look enough? Just about all of the dryers and ranges I have seen since that change have had the 3-wire cord pre-installed or shipped without one at all... Each had bond strap that could be removed. While most had instructions for removing it, some had those instructions separate either on another paper as an insert, or available on the web. Usually that bond is right there in the J-bx for the cord. I came across one some time ago that had a tag on the bond strap with a picture of "scissors" and picture of a 4-wire plug. I guess they simply meant 'cut it'????

 

[brother]

Maybe you didn't look, or look enough? Just about all of the dryers and ranges I have seen since that change have had the 3-wire cord pre-installed or shipped without one at all... Each had bond strap that could be removed. While most had instructions for removing it, some had those instructions separate either on another paper as an insert, or available on the web. Usually that bond is right there in the J-bx for the cord. I came across one some time ago that had a tag on the bond strap with a picture of "scissors" and picture of a 4-wire plug. I guess they simply meant 'cut it'????

I was referring to cooking equipment in commercial kitchens, not dryers and washers in residential.

 

[Sierrasparky]

Well, this is mostly to vent. Been working on alot of kitchen equipment lately, and I know the NEC doesnt govern the manufacturers, but it just bugs me when they use the 'egc' as the neutral. Basically, they need a 120/208 4 wire receptacle, (2 hots 1 neutral 1 ground) but they only specify 208 (2 hots and 1 ground).

It's not that they use the EGC as the ground, They are using the Neutral as an EGC. I don't think it is permissable to use a un-insulated wire for the Neutral in this instance.

 

[mcclary's electrical]

the change was '96,,,,,,and yes,,,there should be a way to seperate the two if you look close enough. sometimes the bond is not in the junction box,,,in fact,,,,it's usually not. You gotta find it,,,,and confirm seperation with meter when you cut it.

 

[goldstar]

Most are shipped for the 'old way', and have conversion instructions adding a 4-wire cord.

But most end users or the delivery men don't read those instructions or NEC 250.140

I'm amazed I still see ranges that have 4 wired cords but the neutral bonded at the range. Seems SOP for "big box store" installs.

That's in a nutshell Gus. To make matters worse they're shipping all units out with a 50 amp cord irrespective of whether the unit requires a 30 amp or 50 amp circuit. The mentality seems to be "Why ship it with a 30 amp cord if a 50 amp cord covers all bases"

I don't think it is permissable to use a un-insulated wire for the Neutral in this instance.

There are some instances where this is acceptable. Read 250.140 Ex (3)

 

[Cold Fusion]

---Internally they use the ground to carry the current for their 120 volt parts. (ie electronic boards etc). Once in a while Ill run into one that has a control transformer in it. but too many times I see where they bond to the ground their circuits. ---

Brother -
Are you sure the mfgs are using the grounding conductor to carry the control board current? I'm thinking the electronic boards are not 120V but maybe 12V or 5V. With no control transformer, they would have to be using a switching power supply and that could be run from the 240V (or 208V) just as easy as 120V.

Are you seeing current on the egc? If so, how much?

cf

 

[e57]

I was referring to cooking equipment in commercial kitchens, not dryers and washers in residential.

It is the same code requirement, and the same manufacturers for the most part.

FWIW - most of the commercial kitchens I do are old equipment bought at auction, and to be installed in kitchen spaces that I am remodeling. There are often cases where I do not necessarily have to do anything - but do anyway.... See below: (CA is '05, but this code changes little '02~'08)

Commentary from the 2002 NEC

Section 250.140(4) applies only to existing branch circuits supplying the appliances specified in this section. The grounded conductor (neutral) is no longer allowed to be used for grounding the metal non?current-carrying parts of the appliances listed in 250.140. Branch circuits installed for new appliance installations are required to provide an equipment grounding conductor for grounding the non-current-carrying parts.
Caution should be exercised to ensure that new appliances connected to an existing branch circuit are properly grounded. An older appliance connected to a new branch circuit must have its 3-wire cord and plug replaced with a 4-conductor cord, with one of those conductors being an equipment grounding conductor. The bonding jumper between the neutral and the frame of the appliance must be removed. If a new appliance is connected to an existing branch circuit without an equipment grounding conductor, where the neutral conductor was previously used for grounding the appliance, a bonding jumper must be installed at the appliance terminal to connect the frame to the neutral.
The grounded circuit conductor of an existing branch circuit is still permitted to be used to ground the frame of an electric range, wall-mounted oven, or counter-mounted cooking unit, provided all four conditions of 250.140 are met. The grounded circuit conductor is also permitted to be used to ground any junction boxes in the circuit supplying the appliance, and a 3-wire pigtail and range receptacle is permitted to be used, even though the circuit to the receptacle contains a separate equipment grounding conductor.

See also; 250.142(B) exception #1 in the '08 NEC if that is what you are on?

 

[e57]

But most end users or the delivery men don't read those instructions or NEC 250.140

I have been called to change 4-wire outlets to 3-wire. (Because that was what was shipped on the unit) I bring a 4-wire cord instead....