Disco rqd?

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jes25

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Electrician
What code section applies to the requirement, or lack thereof, to install a service disconnect for a machine. The installation in question is a piece of manufacturing equipment.
 
Is it actually a "Service" disconnect (disconnecting utility service).. if so Art 230.70
If you are referencing a switch to turn of power to the machine, if it contains a motor Art 430 Part IX.
If it contains no motor, more details might be required to classify the machine.
 
No it's not that kind if service disconnect. It's a so you can service it disconnect. It has several motors, but lots of other stuff, like PLC's and lights . The machine is used to machine parts; think robot in a box.
 
look at 670.2 does it meet that definition, if yes than look at 670.4 (b)
 
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This machine meets the definition in art 670. 670.4B pretty much just says I need to have one with no other requirements.
 
Does machine have a disconnect already on it?

May seem like stupid question but some people think you still need an additional disconnect.
 
kwired said:
Does machine have a disconnect already on it?

May seem like stupid question but some people think you still need an additional disconnect.
Click to expand...

Not a stupid question at all. Most all machine panels have a disconnect and interconnected lock out system. Installing a disconnect is just a waste of money and time.
 
jes25 said:
What code section applies to the requirement, or lack thereof, to install a service disconnect for a machine. The installation in question is a piece of manufacturing equipment.
Click to expand...

The NEC covers some but not all topics necessary for a piece of industrial machinery. The NEC tells you the machine needs a disconnect but stops there. If you stop with the NEC when wiring an industrial machine then you're gonna get someone killed.

At a minimum you must comply with:
OSHA 1910 Subpart S
OSHA 1926 Subpart K
* OSHA currently is very close in content to NFPA70E 2004 though 2009 is released
NFPA70 2005/2008 depending on your state.

But the above legal requirements do not adequately cover industrial machinery. There is no legal guide but there are numerous industrial standards that your company can adopt.

I suggest:
NFPA79 2007 "Electrical Standard for Industrial Machinery 2007 Edition"

The above standard will explain good practices for disconnecting industrial machinery. It can be viewed on the NFPA website:
http://www.nfpa.org/aboutthecodes/list_of_codes_and_standards.asp?cookie_test=1
 
By service, are you working on the mechanical or electrical. If electrical, it could make living with 70E easier by not having live components in the cabinet while servicing.......just a thought

and if it is a manufactured piece of equipment, see NFPA 79 - 5.5 Devices for Disconnecting (Isolating) Electrical Equipment (2007) for Industrial Machinery
 
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