Do I need a disconnect

[binney]

I have a 225 amp 3ph machine 240v grounded B, (it's some type of planer in a cabinet shop). It's 140' away from the panel. It has a junction box with a terminal block in it, from the top side of the terminal block it's wired to the on/off sw. The on/off sw disconects all 3ph's.

For service puposes the on/off would be sufficient as a disconnect. My boss insists that seing the panlel is not within sight, I need another disconnect, before the machine, because there is still power going into the machine. But seing there's a disconnect on the machine for safety, maintenance, and servicing purposes, why would I need another one? And if I do why wouldn't a breaker lockout work?

 

[tonyi]

Re: Do I need a disconnect

Is this circuit dedicated to the unit or is the unit tapped off a feeder going to other things in the shop (where the tap rules and tap OCPD requirements might apply)?

 

[binney]

Re: Do I need a disconnect

it's a dedicated run, back to the original panel

 

[pierre]

Re: Do I need a disconnect

Is the switch that you mention designed to interrupt locked rotor current, and does it provide overload protection?

IF not you will be required to provide a disconnect.

Pierre

 

[hurk27]

Re: Do I need a disconnect

Binney
What kind of on/off switch is it that handles 225 amps?

Is the switch part of the machine? mounted on the machine?
Is there a motor starter with O/Ls in it. Just having a means of disconnection to allow the removal of the machine also needs a disconnect within site (50' max) to remove power from the disconnection point. The breaker serving the circuit will be the short circuit protection so overload should be the only concern but I'm not picturing it.

 

[binney]

Re: Do I need a disconnect

The sw is part of the machine. There's several motors on this thing, there'a a control cabinet on it, which is under lock and key, inside is where I imagine all the control wiring and motor starters would be as far as OL's I don't know, but i would imagine there are.

So, although it takes two fork lifts to move this thing and it's now mounted to the floor. I still need a seperate disconnect, not a lock out in case it's to be removed.

 

[hurk27]

Re: Do I need a disconnect

The switch is only a part of the control wiring, It is not a means of disconect as it does not remove power from this machine. if somone were to go to work on it there would be power on all of the controls and the top side of the motor starter. this would fall under the requirments of 110.26 and 430.74 And or 430.101 through 430.113
So yes you need a disconect that would remove all power including control voltage to this machine.
There are other OSHA requirments too as for emg stops dead man switchs. so to cover your self I would find out what is required from OSHA too.

 

[kiss]

Re: Do I need a disconnect

Based on the information given, I have installed on similar jobs a 400A NON FUSED Disconnect at the equipment. Non fused since a breaker or fuses were used at the panel or distribution point.

 

[toms422]

Re: Do I need a disconnect

Did anyone notice that the 5' requirement for a disconnect to a hot tub was dropped for a residential installation in the 2002 code?

 

[jimwalker]

Re: Do I need a disconnect

Had there been a disconnect my niece would be alive today.Her hair got caught in the drain.
Would not a plug and cord fill this requirement?

[ December 25, 2003, 07:54 PM: Message edited by: jimwalker ]

 

[binney]

Re: Do I need a disconnect

The switch is only a part of the control wiring, It is not a means of disconect as it does not remove power from this machine. if somone were to go to work on it there would be power on all of the controls and the top side of the motor starter.

The switch is not a part of the control wiring, it is fed with the 3legs of line voltage coming into the machine. Therefore the only power that would be present, when off, would be the power coming into the terminal block for this sw.
I don't see any difference in using this as the disconnect or having the disconnect mounted right next to it on the wall.

(as far as what type of sw this is and it's rating I don't know. The machine was shipped over from germany and my german isn't so good. The switch does disconnect all power except what is feeding it.)

Had there been a disconnect my niece would be alive today.Her hair got caught in the drain.
Would not a plug and cord fill this requirement?

I'm sorry about your niece. This machine does have a disconnect. The question is wether or not it's sufficient to meet the code. I had the disconnect with me and would have put in in, but the customer refused to pay for a disconnect that he didn't need.

When your dealing with a world where the customer is always right, you need to have concrete evidence of why there wrong.

 

[hurk27]

Re: Do I need a disconnect

I didn't know the switch did in-fact disconnect all of the voltage to the machine. as I was thinking this was some kind of off/on snap switch. and couldn't figure it handling 225 amps. but if it does disconnect all the power and a electrician working on this machine with out being exposed to any live circuits with this switch off while performing normal maintenance on it then I guess it would comply. But the expose terminal block kind of worries me without seeing it.

 

[iwire]

Re: Do I need a disconnect

Wayne this sounds like he may have an IEC style disconnect in the cabinet these are small and compact compared to NEMA disconnects, also the line and load sides are guarded in a way that can not be removed.

The terminal screws are deeply recessed so you can not accidental come in contact with them.

 

[binney]

Re: Do I need a disconnect

Wayne this sounds like he may have an IEC style disconnect in the cabinet these are small and compact compared to NEMA disconnects, also the line and load sides are guarded in a way that can not be removed.

The terminal screws are deeply recessed so you can not accidental come in contact with them.

It sounds like what i'm looking at. I have a picture of it but i don't know how to post a picture in a post.

 

[toms422]

Re: Do I need a disconnect

Disconnects should always be there. Emergencies happen in residential and public uses. The 5' rule should be there in case of contact. Direct hook ups also remove the gfi requirement.