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!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Forum Software Upgrade coming soon...
by gfretwell
01/17/17 01:16 PM
Why cables look like they do
by Texas_Ranger
01/17/17 12:33 PM
Re: Fabricating Guards out of Lexan?
by ghost307
01/17/17 11:21 AM
Would ELV branch circuits be a good idea?
by ghost307
01/17/17 11:18 AM
100% breakers?
by Texas_Ranger
01/16/17 06:13 AM
New in the Gallery:
Desk-mounted "power-board"
Shout Box

Top Posters (30 Days)
HotLine1 19
Webmaster 14
Trumpy 12
ghost307 12
gfretwell 10
Who's Online
2 registered (ghost307, gfretwell), 0 Guests and 78 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#7698 - 02/16/02 06:27 PM fused or non fused
amptrap Offline
Junior Member

Registered: 02/09/02
Posts: 3
Loc: dallas tx
maybe i should already know this but i was wondering when you need a fused disconnect and when you dont. i was telling a friend he needed a fused disconnect on a duct heater because it had no internal overloads. it just had a disconnect switch for working inside the heater
_________________________
=0

Top
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....

#7699 - 02/16/02 06:31 PM Re: fused or non fused
Nick Offline
Member

Registered: 08/13/01
Posts: 603
Loc: Riverside, CA
A heater would not require overloads. It is protected by the branch circuit over current device. A non-fused disconnect is fine in this application.

Top
#7700 - 02/16/02 06:34 PM Re: fused or non fused
amptrap Offline
Junior Member

Registered: 02/09/02
Posts: 3
Loc: dallas tx
so what is a good rule of thumb to use fused or non fused. does every resistive load not need a fused disconnect.
_________________________
=0

Top
#7701 - 02/16/02 06:55 PM Re: fused or non fused
Nick Offline
Member

Registered: 08/13/01
Posts: 603
Loc: Riverside, CA
Check the manufacturers nameplate. Most equipment will state weather or not a fuse is required. For instance, if a piece of equipment states a maximum fuse size of a specified value, you must use a fuse to protect the unit. Doing otherwise would void the listing and be a violation of 110.3(B). If it states maximum fuse or circuit breaker you could use either. You could use a breaker as protection and a non-fused disco at the unit.

Top
#7702 - 02/16/02 06:59 PM Re: fused or non fused
amptrap Offline
Junior Member

Registered: 02/09/02
Posts: 3
Loc: dallas tx
thanks a bunch nick i guess i never thought of it like that.
_________________________
=0

Top
#7703 - 02/21/02 03:10 PM Re: fused or non fused
Steve Miller Offline
Member

Registered: 08/30/01
Posts: 322
Loc: Loudoun Cty, VA
Be careful on the AC/Heat pump units. Some say max fuse size and some say max fuse/HACR CB size. If it says only max fuse then you need the fuse (someplace in the circuit) regardless of the breaker.

Top


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