Need another dis-connect or not?

[brinkmann27]

We have a customer who is starting to build self contained environmental remendiation trailers for use in Florida. These trailers are similar to the ones you see the lawn maintenance guys use. Inside the trailer will be a compressor, vacuum pump and a couple of liquid pumps. Most of the time they are in a hazardous zone.

The control panel we manufacturer goes on the trailer front(outside) and is a NEMA 4 enclosure (outside the zone). On our panel we have a main dis-connect with a thru door operator made by ABB. This dis-connect is lockable in the off position (padlock). Is our customer required to have dis-connects at each unit inside the trailer ? Most of the time he passes inspection without them. But he has a couple of times in which he had to put dis-connects at the units. Are the additional dis-connects really required the code?

Thanks in advance

 

[jraef]

As long as there is a clear "line of sight" between the equipment and the lockable disconnect, there should be no problem. Even if there is not, the fact that it is lockable and is the only source of power may make it OK if there are other extenuation circumstances, chiefly the fact that it is a temporary / portable system. In those cases it is usually necessary to provide for at least 3 padlocks to be applied to the disconnect. There are padlock expanders that allow that to be done with an existing 1 hole switch assembly.

"Venditori de oleum-vipera non vigere excordis populi"

 

[mc5w]

Most external disconnect handles for industrial enclosures will accomodate 3 or 4 padlocks.

 

[jraef]

Not the small round ones available from most IEC component mfgrs like ABB. They have a single round hole, however a drill bit can solve that. ABB's pistol grip for larger disconnects can handle 3 padlock shafts if you know where to look, but no more than that.

"Venditori de oleum-vipera non vigere excordis populi"