ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
LED retrofit flickers
by rmiell. 01/18/19 08:49 PM
Israel
by Texas_Ranger. 01/14/19 07:12 AM
Free Code class in Maryland 1/16/2019
by Admin. 01/12/19 05:43 PM
Calling all Non-US members!! (Non-US only)
by RODALCO. 01/12/19 02:37 AM
sec cable code conflict
by jake2018. 01/11/19 07:36 PM
New in the Gallery:
What is this for?
Plug terminals
Who's Online Now
0 registered members (), 35 guests, and 14 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Wye Delta Start Closed Transition #193952
05/01/10 12:03 AM
05/01/10 12:03 AM
D
DYNAMITE  Offline OP
Member
Joined: Dec 2003
Posts: 36
Winkler, MB, Canada
Would anyone know how to size the resistors on a Wye start/delta run closed transition starter? Say for a 50 Hp 230V motor?

Tools for Electricians:
Re: Wye Delta Start Closed Transition [Re: DYNAMITE] #194021
05/05/10 03:48 AM
05/05/10 03:48 AM
Scott35  Offline

Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,715
Anaheim, CA. USA
I believe the Resistors would be sized ("size" = Resistance value - in Ohms), so as to allow the same level of Current that the "Wye" configuration does.

Example:
Motor's FLA = 130 Amps
Starting (Wye Connection) Ampere = +/- 75 Amps
Resistors are sized to allow +/- 75 Amps at rated Voltage.

I am not 100% sure on this, so let me find some references, then reply back.

Scott


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Re: Wye Delta Start Closed Transition [Re: Scott35] #194026
05/05/10 10:54 AM
05/05/10 10:54 AM
D
DYNAMITE  Offline OP
Member
Joined: Dec 2003
Posts: 36
Winkler, MB, Canada
That makes sense to me. The smaller you make them the closer to normal current you have. The next question is Watt ratings. The resistors are only in the circuit for a split second in the transition between wye and delta so would you need full power ratings(Peak I^2 R) on them?


Featured:

2017 Master Electrician Exam Preparation Combos
2017 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 4
Popular Topics(Views)
252,839 Are you busy
189,628 Re: Forum
179,294 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.021s Queries: 15 (0.005s) Memory: 0.9509 MB (Peak: 1.0767 MB) Zlib enabled. Server Time: 2019-01-24 00:24:56 UTC