ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Lock-down Thread
by gfretwell - 05/10/21 06:12 PM
Do You Travel?
by HotLine1 - 05/10/21 02:17 PM
Any Woodworkers here?
by Trumpy - 05/10/21 07:22 AM
Your favourite food?
by Trumpy - 05/10/21 07:07 AM
Just be aware of this...
by Trumpy - 05/10/21 06:47 AM
New in the Gallery:
2020 - 2021 Winter Project
Garden 2021
Who's Online Now
0 registered members (), 21 guests, and 14 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Sizing for heatstrips #180123 08/13/08 10:45 PM
Joined: Feb 2008
Posts: 193
S
schenimann Offline OP
Member
I'm pricing out a job for a local plant. They had a gas heater go out and they are wanting to replace it with an electric heater to seee if there are any savings.

They are installing three sets of two 25kw heaters(480v). This is 60.1 amps per set. This is for 1 machine with the pontential of adding 5 more.

I'm feeding them from a busbar to a breaker panel to the heaters. I'm going to size my wire according to this number #6THHN.

Do I need to size my wire feeding the breakers at 180 amps or can I derate?

If I add another machine am I then up to 360 amps? Or five machines and 1080amps?

Thanks for your expertise.

Work Gear for Electricians and the Trades
Re: Sizing for heatstrips [Re: schenimann] #180124 08/14/08 12:23 AM
Joined: Jul 2004
Posts: 9,607
G
gfretwell Online Content
Member
I don't see any reason why you could use anything less than 100% of connected load and if this is continuous load it would be 125%.


Greg Fretwell
Re: Sizing for heatstrips [Re: gfretwell] #180129 08/14/08 06:21 AM
Joined: Feb 2008
Posts: 193
S
schenimann Offline OP
Member
Thanks Greg, I was going the wrong way with my size.


Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
RH1
RH1
California
Posts: 22
Joined: August 2009
Show All Member Profiles 
Top Posters(30 Days)
Trumpy 19
Admin 8
Popular Topics(Views)
278,810 Are you busy
211,973 Re: Forum
199,011 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3