Previous in Forum: Wind Turbine Torque Elctrical vs Mechanical?   Next in Forum: Clarification Regarding Oversizing of Transformer
Close
Close
Close
13 comments
Rate Comments: Nested
Commentator

Join Date: Aug 2010
Posts: 56

Not Switching to Delta

12/18/2012 4:38 PM

Hey all

I have a star delta connection. My motor is still not connected. The problem my delta contactor is catching for sec and goes off. and everything goes off. The breaker doesnt trip. I dont have the wiring diagram and the panel is really messed up so really hard to troubleshoot. I am guessing some thing is wrong the wiring. May be some NC NO interchanged. I already changed delta and star contactor

Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Guru

Join Date: Oct 2008
Posts: 42355
Good Answers: 1693
#1

Re: Not switching to delta

12/18/2012 4:59 PM

Good luck. Let us know how it comes out.

Have you tried it with the motor connected?

How do you re-energize the circuit?

I think you should hire an electrician, soon.

Register to Reply
Guru
United Kingdom - Member - New Member

Join Date: Aug 2010
Location: Resting under the Major Oak
Posts: 4347
Good Answers: 181
#2

Re: Not Switching to Delta

12/18/2012 6:14 PM

Probably quicker to rewire it.

__________________
The reports of my death are greatly exaggerated.
Register to Reply
Guru

Join Date: Oct 2008
Posts: 42355
Good Answers: 1693
#3
In reply to #2

Re: Not Switching to Delta

12/18/2012 6:32 PM

That's why he should hire an electrician.

Register to Reply
Commentator

Join Date: Oct 2009
Location: Dubai,UAE
Posts: 62
Good Answers: 2
#4

Re: Not Switching to Delta

12/18/2012 8:52 PM

Rewire your starter circuit as per below diagram.

__________________
There are no shortcuts on the road to a great experience.
Register to Reply
Guru

Join Date: Jun 2010
Location: srilanka
Posts: 2725
Good Answers: 5
#11
In reply to #4

Re: Not Switching to Delta

06/29/2013 12:37 AM

What is the advantage of connecting indicating lamps to 24V instead of 220V?.

__________________
pnaban
Register to Reply
Guru
United States - Member - New Member Engineering Fields - Power Engineering - New Member

Join Date: Sep 2006
Location: California, USA, where the Godless live next door to God.
Posts: 4665
Good Answers: 804
#12
In reply to #11

Re: Not Switching to Delta

06/29/2013 11:36 AM

"What is the advantage of connecting indicating lamps to 24V instead of 220V?." How is this related to this thread?

__________________
** All I every really wanted to be, was... A LUMBERJACK!.**
Register to Reply
Power-User

Join Date: Jun 2012
Posts: 123
Good Answers: 7
#13
In reply to #11

Re: Not Switching to Delta

06/29/2013 3:08 PM

"What is the advantage of connecting indicating lamps to 24V instead of 220V?"

Connecting indicating lamps to low voltage allows you to make "on-line" replacements of broken or burned-out bulbs without danger of touching a 220V conductor.

Register to Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 21017
Good Answers: 795
#5

Re: Not Switching to Delta

12/18/2012 11:27 PM

Some Y-Δ timings can result in a very large current upon switching to Δ. In turn, this could cause enough voltage dip to drop out the Δ contactor.

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Register to Reply
Active Contributor
Iran - Member - New Member

Join Date: Nov 2012
Location: IRAN -
Posts: 14
Good Answers: 1
#6

Re: Not Switching to Delta

12/19/2012 2:16 AM

Iv already faced with this problem.while motor is not connected and your circuit start with Star stage and after that timer command to connect Delta stage ,it shows holding contact DELTA contactor doesnt match correctly and cause circuit goes off.

__________________
we all switch to perfection
Register to Reply
Participant

Join Date: Dec 2008
Posts: 3
#7

Re: Not Switching to Delta

12/19/2012 2:58 AM

Have you checked your timer? It is posible that timer may not be holding delta contact continuously.

Register to Reply Score 1 for Good Answer
Guru

Join Date: Oct 2007
Location: India
Posts: 1246
Good Answers: 34
#8

Re: Not Switching to Delta

12/19/2012 3:39 AM

What make & type number starter is it? You may be able to download the schematic circuit diagram. Have you tried?

Register to Reply
Power-User

Join Date: Jun 2012
Posts: 123
Good Answers: 7
#9

Re: Not Switching to Delta

12/19/2012 7:43 AM

Hi pickid,

You wrote that after the delta contactor catches for a second "everything goes off." Assuming your starter uses three contactors (line, star, delta) and that you operate it using a momentary stop/start pushbutton set, then the problem seems to be in the holding circuit.

Try this --- when you push the start pushbutton, don't release it right away. Hold it in firmly until the delta contactor catches. If the delta contactor remains energized then check out the following possibilities:

  • Voltage drop in the control circuit caused by loose wiring connections, control transformer undersized or defective, delta contactor sticks drawing excessive current, etc.
  • The mechanical jolt of the delta contactor pulling in causes the auxiliary NO holding contact of the line contactor to drop out momentarily.

Hope this helps!

Zvi

Register to Reply
Power-User

Join Date: Apr 2011
Posts: 188
Good Answers: 6
#10

Re: Not Switching to Delta

12/19/2012 7:50 AM

Very Carefully.... Pull the Disconnect and LOCK IT OUT!

Then Lock out the Control Power if external

Check every Auxiliary Contact that you can find, check the timers, check the relays if you have them. While you're at it, Check the Starters..

If you find the problem and it runs ok after:

Schedule it for a proper Panel Rewire/Upgrade/Cleanup with proper schematics during downtime....

Register to Reply
Register to Reply 13 comments

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Copy to Clipboard

Users who posted comments:

AHMAD REZA CHANGIZ (1); Aseer (1); corbinstein (1); Joshi (1); JRaef (1); lyn (2); naresh_mokal (1); pnaban (1); TonyS (1); Tornado (1); Zvi (2)

Previous in Forum: Wind Turbine Torque Elctrical vs Mechanical?   Next in Forum: Clarification Regarding Oversizing of Transformer

Advertisement