The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Parking lot pole light swap....
by gfretwell
10/24/16 08:46 PM
International Wire Colour Codes
by Tjia1981
10/23/16 12:08 PM
Son of Sparky
by HotLine1
10/20/16 07:43 PM
Speaking of Plugmold ...
by gfretwell
10/17/16 02:37 PM
Broken battery charger? Check for cobwebs!
by gfretwell
10/17/16 02:30 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 14
HotLine1 7
ghost307 7
renosteinke 6
Potseal 4
Who's Online
0 registered (), 257 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#25210 - 05/01/03 04:22 PM Motor Starters and heaters
sparkync Offline

Registered: 10/17/02
Posts: 811
Loc: NC
Quick question.. I don't get to be on here much anymore...Been busy working
I have an industrial job to do. My strong points are in residential, although I've done a little of everything practically.. I have 3 old 3 phase motors to run circuits to. One is a 5 HP motor that already has a "Mitsubishi Electric" starter mounted on the frame of the machine. It has an internal adjustment for amps, but I can't find any heaters to protect the motor. Just need a little advice. It seems that I will have to mount a starter with heaters ahead of the existing starter, which by the way has a "stop,start" button on it and also a "run, stop" button on it. It is obviously a Japanese made machine. Also on the nameplate, it has 50hz instead of 60hz. The business I am doing the wiring for, said it had been running in another part of the building fine.
Also I'm kind of confused at this moment on how I will wire the extra starter( with heaters) in conjunction with the one already on the machine???? That is if it is necessary. Like I said, motors and industrial work are not my specialty, any advise would be appreciated..

**Also He wants 2 old exhaust motors wired which are on the outside, up about 15 ft. toward the top of the vent pipe, which is approximately 4 ft. in diameter. This is to exhaust fumes from a spray booth area. The disconnects and motors are already wired. The conduit from the disconnects are stubbed out inside the building. I will have to set a 3 phase panel and/or a set of 3 phase manual starters with heaters on the inside so the motors can be controlled. If I set the controllers outside of the "spray area", will that get me out of the "hazardous area"?? Also where the conduits are going out of the building to the motors, one has a "seal off" on the conduit. Is this code also??? Any help will be greatly appreciated.. Hope it all makes sense. Thanks a lot.... Steve....

By the way, the lights in the area are open 8 ft. flourescent strips wired in emt with set screw connectors. Should this area not be "explosion proof" etc.?????? Thanks again...

Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#25211 - 05/01/03 07:20 PM Re: Motor Starters and heaters
spkjpr Offline

Registered: 12/01/00
Posts: 226
Loc: Sedalia,MO, USA
Sparkync, the starter on the motor sounds like an IEC version. The overloads are adjusted with the dial. Our fluorescent light in the spray booths are enclosed , explosion-proof fixtures with heavy glass lenses. The NEC sect 500 (in the 99 book) has some distances and info on what is the dangerous area. Hope this helps.

#25212 - 05/01/03 07:44 PM Re: Motor Starters and heaters
fla sparkey Offline

Registered: 08/03/02
Posts: 46
Loc: Winter Haven, Florida USA

Check article 516-2 in the 1999 NEC, especially figure 516-2(b)(2)and 516-2(b)(4) for an answer to your spray booth question. I had to wire an ansul system for one about a year ago. Believe it or not the fire sprinkler company installed the j-box to their equipment in the area next to the exterior door of the booth. The box was not rated for use in a hazardous location and they had to move it before I would wire the ansul system.

[This message has been edited by fla sparkey (edited 05-01-2003).]

#25213 - 05/01/03 07:58 PM Re: Motor Starters and heaters
sparkync Offline

Registered: 10/17/02
Posts: 811
Loc: NC
Thanks guys, I'm in the process of trying to figure out these articles in 516 in the 99 Code. The more I read, the more complex this job seems. Right now, the area he plans on using for the spraying is not enclosed. He said He would probably put plastic up to keep the fumes from going in the rest of the building. If it means anything to anybody out there, he said the spray he uses is water based and not oil based??? I'm trying to figure out what's going on here. I don't want nothing "blowing up"........ because of fumes.... Thanks a lot.. I'm still searching. .... As for the "Mitsubishi" contactor on the other motor, I'm finding out it probably is the "heaterless design" that uses solid state overload and adjustable trip point relays.. I feel like this satisfies the code requirements on motor protection... Keep the info coming.. I want to make sure I get this right.... Steve.

#25214 - 05/01/03 10:39 PM Re: Motor Starters and heaters
frenchelectrican Offline


Registered: 02/06/03
Posts: 938
Loc: Wi/ Paris France { France for ...
ok about the spray booth there is a fine line there and my brother in law have pretty large spray booth i setup quite few years ago and the spray booth have fixure set up allready the reg. flourescent fixure are mounted outide of spray booth and have tempered safety glass on it and the rest of area is standard flourscent lamps strip fixure and by my nec code say first 7 feet front of spray booth is classifed but futher away from spray booth is non classifed area and i allready have the inspecter approved and check everything and meet the code that time i install it.

merci marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

#25215 - 05/02/03 10:55 AM Re: Motor Starters and heaters
Joe Carpenter Offline

Registered: 12/19/01
Posts: 55
Loc: USA
On the Spray booth issue I would consult with your local AHJ. It is common for different areas to have codes that are tighter then the NEC.

#25216 - 05/02/03 01:21 PM Re: Motor Starters and heaters
mlk682 Offline

Registered: 04/14/03
Posts: 46
Loc: Foley Mn
Steve, I would caution you on the overload block ,the name plate data is going to be for a motor running at 50 hz so the rpm is obviously going to be different but it also is probably set up for European voltages (correct me if I am wrong) which will make the precalculated nameplate data incorrect. Send me the nameplate info and I can run your calculations for you.



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals