controls inside starters?

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GlennH

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With all the emphasis on safety nowadays, can someone tell me how they allow control panels to be installed inside starters or VFDs? I've attached a picture of a Sq D VFD I mounted a couple days ago on a cooling tower.

The drive has all kinds of stickers on the outside telling you to shut off all power before opening the door, But how is one to operate the control without the power on??

Sq D isn't the only one, couple weeks ago I had a large Carrier air handler with the VFD control mounted right next to the incoming power(480v) terminations.

Same deal, turn off all power but how do you operate control?

How do they get a UL listing? vfd.jpg
 

don_resqcapt19

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There are remote operator control panels available for most all VFDs. I agree that with the control panel inside, you could not set up the drive without being exposed to energized parts.
 

Jraef

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That keypad could be mounted to the exterior door, someone decided they didn't want to pay a little extra for that. But yes, you have identified a problem that is looming as enforcement of NFPA70E ramps up. You technically might be required to wear some fairly odious PPE in order to program the drive.
 
Hard to tell from that picture, but that little pancake fan looks like it's just hanging there from a tie wrap or two off of the DIN rail. Pretty unprofessional design, IMO. Only way to make that a "safe" install would have been to have the keypad remote mounted -OR- have a separately derived control power source. Since most drives tend to take their control power from line, that probably wasn't an option for this install. And jeez - who taught the designer how to loom control wires??? Not picking on you - it's not your design (is it?) but man - whoever dreamed up that one needs to be kicked back to school!
 
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don_resqcapt19

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...You technically might be required to wear some fairly odious PPE in order to program the drive.
I am not sure 70e would permit that work even with PPE. Is setting up a drive "troubleshooting"? If not, then it would not be likely that the rules would permit you to set up that drive no matter what PPE you had on.
 
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Items we built just a few years ago are no longer safe, just as houses we wired a few years ago are no longer considered adequate by todays codes. We use remote display mounting where we can now but I can point to a complete control system that UL put their little stamp of approval on, that IMO, was unsafe even 6 years ago.
 

pfalcon

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Location
Indiana
I am not sure 70e would permit that work even with PPE. Is setting up a drive "troubleshooting"? If not, then it would not be likely that the rules would permit you to set up that drive no matter what PPE you had on.

70E:130.1(A)(2) Infeasible :: Permits working on energized equipment that due to design cannot be worked on in any other manner.

Troubleshooting is an exemption to an energized work permit not a reason to work energized.
 

iwire

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70E:130.1(A)(2) Infeasible :: Permits working on energized equipment that due to design cannot be worked on in any other manner.


It is my understanding that infeasible means cannot be done.

In this case it can be done by removing the drive from the MCC or purchasing a remote type control pad and installing outside the MCC.

Keeping in mind the only time this would come up is if someone gets hurt, than you have to justify the decisions made.
 

pfalcon

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Location
Indiana
It is my understanding that infeasible means cannot be done.

In this case it can be done by removing the drive from the MCC or purchasing a remote type control pad and installing outside the MCC.

Keeping in mind the only time this would come up is if someone gets hurt, than you have to justify the decisions made.

"Cannot be done" can only be in the present tense given the current design. Otherwise article 130 is completely pointless in its entirety. ANY system can be designed with redundancy, failovers, backups, etc. Redesign is always a cost/risk analysis sort of like life insurance. If no one ever dies on it then you paid too much.
 

pfalcon

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Location
Indiana
Has anyone been fined for this type of installation where an injury or death has not occured?

That would be the EU for not following code that says such things must be placed for maintenance to avoid known hazards. In the US we'll wait for someone to be injured and then sue for designing a knownable hazard.
 

iwire

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We can split hairs about this all year long but I have no doubt at all that if someone gets hurt OSHA will fine the company for unsafe work practices.
 
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