Is this compliant with Article 400

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weressl

weressl

Esteemed Member
Location
Texas by the Gulf, geat crab, great shrimp
Transformer manufacturers often use SO cords with prefabricated connectors to hook up various devices tot he control box. One example of this type is installation is depicted here:
http://www.flickr.com/photos/11903290@N08/4078077293/
My question is:
How is this complies with

400.7 Uses Permitted.​

(A) Uses.
​
​
Flexible cords and cables shall be used only for​

the following:

(1) Pendants
(2) Wiring of luminaires
(3) Connection of portable luminaires, portable and mobile signs, or appliances
(4) Elevator cables
(5) Wiring of cranes and hoists
(6) Connection of utilization equipment to facilitate frequent interchange
(7) Prevention of the transmission of noise or vibration
(8) Appliances where the fastening means and mechanical connections are specifically designed to permit ready removal for maintenance and repair, and the appliance is intended or identified for flexible cord connection
(9) Connection of moving parts
(10) Where specifically permitted elsewhere in this ​
​





Code​

(B) Attachment Plugs. ​


Where used as permitted in 400.7(A)(3), (A)(6), and (A)(8), each flexible cord shall be equipped with an attachment plug and shall be energized from a receptacle outlet.
Exception: As permitted in 368.56.​
 
Pierre C Belarge

Pierre C Belarge

Senior Member
Location
Westchester County, New York
Most times the manufacturer is following a different standard.
They have their equipment tested with the said wiring methods and since they are on a more strict wiring regimen, they can produce the equipment in that fashion.
Field wiring is not as controlled, so the NFPA leaves less up to the field installer in regards to safety.
 
W

wireguru

Senior Member
weressl said:
Neither apply. It is a sealed and pressurized tank and the instruments don't get removed.
Click to expand...


ok so that rules out 6, but look at the last half of 8. The instruments are clearly intended for flexible cord connection as they have the connectors on them -which then brings the issue of how the instruments are mounted. And is an instrument even an appliance?

I must say, for a piece of equipment that cost as much as that thing (i can only imagine the price tag) the cords look like crap.
 
weressl

weressl

Esteemed Member
Location
Texas by the Gulf, geat crab, great shrimp
wireguru said:
ok so that rules out 6, but look at the last half of 8. The instruments are clearly intended for flexible cord connection as they have the connectors on them -which then brings the issue of how the instruments are mounted. And is an instrument even an appliance?

I must say, for a piece of equipment that cost as much as that thing (i can only imagine the price tag) the cords look like crap.
Click to expand...

The instruments are FITTED with the cord connectors, it is not their standard configuration.

The Bucholz realy for example comes with a threaded conector: http://www.viatin.com/RPRR.htm , and of course made overseas wehre everything is cord connected.

Same is true for the rest of them.

As you can observe they have also used Liquid Tight Flexible COnduit to make a run between the control panel and the liquid preservation enclosure and not visible in the picture they also made a connection to the space heater @ 240VAC in the same fashion for the HV incoming cabinet. The transformer fan on the other side is connected with a cord and it is operating at 240VAC.
 
W

wireguru

Senior Member
weressl said:
The instruments are FITTED with the cord connectors, it is not their standard configuration.

The Bucholz realy for example comes with a threaded conector: http://www.viatin.com/RPRR.htm , and of course made overseas wehre everything is cord connected.

Same is true for the rest of them.

As you can observe they have also used Liquid Tight Flexible COnduit to make a run between the control panel and the liquid preservation enclosure and not visible in the picture they also made a connection to the space heater @ 240VAC in the same fashion for the HV incoming cabinet. The transformer fan on the other side is connected with a cord and it is operating at 240VAC.
Click to expand...


ahhh I thought the connectors were part of the instruments. Do the instruments have npt threads, or something else? I am starting to see that this should all be LFMC, not cord.
 
augie47

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
I'm with Bob (Post #2). If the entire unit came as an assembly (with instruments, cords, etc. intact) and has a NRTL Label, then, to me, it's a listed manufactured assembly. If the cords were added in the field as part of the installation (not preexisting) then I see it as a violation of Art 400.8
 
weressl

weressl

Esteemed Member
Location
Texas by the Gulf, geat crab, great shrimp
augie47 said:
I'm with Bob (Post #2). If the entire unit came as an assembly (with instruments, cords, etc. intact) and has a NRTL Label, then, to me, it's a listed manufactured assembly. If the cords were added in the field as part of the installation (not preexisting) then I see it as a violation of Art 400.8
Click to expand...

Maybe, maybe not.

In the case of liquid filled distribution transformers the listing may not necessarily extend to all parts of the unit. It certainly can not be tested, since each transformer is an unique design and assembly iwth infinite variations of dimensions, materials and components. That is one of the reason why we spell it out in our standard specification that the transformer must comply with NEC, so that any components that are not part of the UL testing and listing DO conform to some nationally recognized standard, the transformer itself to ANSI Standard and so on.
 
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