Our customer has a motor control enclosure with breaker located on inside. You can't access the breaker unless you open the enclosure. Can that main breaker serve as disconnecting means or would we need to install a disconnect before the enclosure? Btw. All the equipment will be Chinese. I haven't seen the equipment so I know what to expect as far as listing or the type of equipment it is. I have just seen pics of equipment.
Disconnect location
- Thread starter mannyb
- Start date
- Status
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
If it is a control panel for "industrial machinery", it would need to meet NFPA 79, which requires that you cannot open the door unless the power is off. If you have to open the door to TURN the power off, that's an obvious violation.
If it is for something other than "industrial machinery", you would probably* still be required to Lock-Out / Tag-Out the equipment to work on it, and the LO/TO must be within sight of the machine. So if you can close the door and no longer see the main disconnect, then it would not qualify.
In many states in the US, you will be required to have an NRTL (Nationally Recognized Testing Lab) approval, such as UL or ETL, in order to connect it.
*Unless it is a "plug-in" piece of equipment.
If it is for something other than "industrial machinery", you would probably* still be required to Lock-Out / Tag-Out the equipment to work on it, and the LO/TO must be within sight of the machine. So if you can close the door and no longer see the main disconnect, then it would not qualify.
In many states in the US, you will be required to have an NRTL (Nationally Recognized Testing Lab) approval, such as UL or ETL, in order to connect it.
*Unless it is a "plug-in" piece of equipment.
timetorun
New member
- Location
- Des Moines, Iowa, United States
Our company just purchased a Hydmech S20A bandsaw. My issue is that the factory installed disconnect does not de-energize the entire machine. As the pictures show, they added a POWER JUNCTION BOX on the opposite side of the machine than the disconnect is on, that we are to run our feeder to. This junction box feeds a 208 volt to 240 volt transformer inside the machine, that is before the disconnect. I can't believe that this is acceptable from a machine manufacturer? Does anyone have any NEC, OSHA, or manufacturing codes to support this issue?
View attachment 2676_001.pdf
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
The only thing that OSHA is going to say is that the owner must provide for a safe work environment when it comes to electrical equipment, including the ability to lock out and tag any sources of energy coming into a machine before working on it. OSHA is not going to say that there must be only one LO/TO point however, so a disconnect back at that junction box would satisfy that.
As I mentioned above, NFPA 79 standard for industrial machinery covers this issue more directly and it would be difficult to argue that a band saw is not a piece of industrial machinery. NFPA 79 WILL dictate that you cannot open the electrical panel without having to disconnect ALL power first.
As I mentioned above, NFPA 79 standard for industrial machinery covers this issue more directly and it would be difficult to argue that a band saw is not a piece of industrial machinery. NFPA 79 WILL dictate that you cannot open the electrical panel without having to disconnect ALL power first.
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