door interlocked disconnect on control panel

Hmm yeah if you take it literally, it looks like the electrical lockout method fails on part b.
 
I have come across many panels where C is sort of ignored. You need the tool to close the cabinet back on the disconnect.
 
Here we are just getting setup with UL and I am not familiar with how literally to take these standards and how the inspectors will take them.

What would you advise? See if an inspector would approve the solenoid?

This is for an OEM customer with up two 200 panels a year so we need the design right the first time around.
 
66.1.5 A door of an enclosure that gives access to uninsulated live parts operating at 50 volts or more shall be interlocked with the disconnecting means such that:

So what if i have an industrial control panel 480VAC and there are no exposed uninsulated parts and everything is IP20?

How do so many OEM's from Europe and get around inspections when they seem to always have an IEC rotary disconnect on the side of the enclosure? Electrical interlock from Hoffman is one possibility however it can only be connected to the disconnect indirectly since it is 120VAC. Also, if i use the electrical interlock how would the defeater mechanism work with the door open?

Sorry, so many questions but realized there are some people in this thread that are well versed on the subject matter.
 
You are discussing UL here, but I would like to point out that in IEC you can ignore the interlock if all parts are fingerproof, all (or most) IEC material from Allen Bradley are. Maybe you have something similar since you have provided a clause:

66.1.2 A door of an enclosure that gives access to uninsulated live parts operating at 50 volts rms ac or 60V dc or more shall be interlocked with the disconnecting means such that none of the doors can be opened unless the power is disconnected.

If you have fingerproofed it, then there are no uninsulared live parts?

/Tim
 
That's what I am thinking......if everything is finger proof and there are shrouds preventing access to the top and bottom of the disconnect is a interlocked door required. My reference to European machines is that they are installed in North America often and I would bet they are not interlocking the door, maybe just using a special key on quarter turn latches to open the door.
 
"The control panel is going on a carousel they build. With where they want to mount the panel, they are limited to around 6" in depth because moving parts of the carousel come past the control panel."

I'd be just as concerned about this...
 
NFPA 79 (2018) 5.3.1.4 Exception 1 allows adding a dead front panel to protect from live components instead of interlock. Dead front has to require tool to open.

Disconnect is still needed but can be remote within sight of the control box.
 
The tool thing is true. It is just. I believe CE does not allow that tool to be a standard screwdriver. When you get right down to it, door interlocks can be overridden by force...especially Square D...they are the worst interlocks I've ever seen(recent experience). Treat them gently or you will override those pieces of junk just by trying just a little bit. Then, they're broken. Again, Square D interlock kits are something to avoid.
 
As another random question, you state this is on a carousel with moving parts all around it, including a crush hazard (6"gap between parts and box) - does this mean it is inside a safety fence of some sort? You could just dump the 480 through a safety contactor upon opening the safety fence, which gets around all of that (I believe), though you'd have VFD powerup time upon reestablishing the safe state of the fence.

But now I'm assuming about layouts. It just sounds this way in my head.
 
Crocodile Tears said:
Yeah, for anything over 120VAC I recall 42" being thrown around a lot, but I don't own the standard or know that we were truly applying it correctly (yay guessing!)
Click to expand...


I've always been told NFPA Electrical Code requires 3 feet clear, and have been in a shop where a fire inspector made them move equipment because it was within 3 feet of a circuit breaker box.


Crocodile Tears said:
..... though you'd have VFD powerup time upon reestablishing the safe state of the fence...
Click to expand...


This can be avoided by adding a contactor after the VFD controlled by the safety circuit.
 
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