Discuss Star Delta starters and timers.... in the Commercial Electrical Advice area at ElectriciansForums.net

If as you say this is linked to the Fire system then this would up the anti- about attempting this as it has a essential safety system latched into it - this is where I would say leave it alone, before I was interested to see if you could figure it but with the extra info supplied Im a little concerned that if you do get it working and you have an actual fire then the system may not operate correctly and may aid the spread off the fire or smoke with major consequences - If yourself your colleagues are unsure as to how the system should act in a fire condition then you need to get in a Fire safety team to asses what the system needs to do to give the best chance of an evacuation of all the workforce.

Thanks for the advice dark wood, I am only assumeing that it may be connected to the fire system I can not confirm nor deny it at this stage.

I have basically decided to go back to basics with it so to speak so I have killed everything and I am now starting to make my own drawing for the circuits as they are wired now.
I am hoping this will give me some idea as to what various parts are for and how they interact with each other.

I also found out a little more history on it today, Apparently it has not worked in atleast 5 years and nobody knows how, why or when so its a bit of a mystery tbh. Also the reason there are no drawings is apparently the company had a falling out with the contractors upon completion of the installation so they refused to hand them over.
Added to the fact the number system is all to cock and nothing is labelled leaves me down ta creek without a paddle!

Doing the cable tracing has brought a few things to light for me which seems rather wrong such as a speed control indicator lamp wired through one of the OL aux's that is apparently not part of the system :s
Also I found the feed to my timer from one of the breakers, But I noticed there are 2 wires in said breaker and the other wire also goes back to my timer! They both go through a series of relay contacts and other coils but 1 goes to A1 and 1 to A2 now that cant be right surely?
I can appreciate depending on what the relays etc are doing the supply could be switched from 1 side to the other but I have never seen a control circuit with 2 feeds to the same thing :s

I will continue to trace wires for the time being as long as my boss permits more for my own curiosty and self learning purposes than anything as I am becoming increasingly doubtfull this thing is going to work anytime soon in its current state :p
 
Good luck but sounds like an uphill battle ...personally I would scrap everything you see and start from scratch ... multiple command wires are common where auto start may be an option or as you said when the fire alarm goes off - it may over-ride the system stopping the fans or running them subject to fire risk assessment.

Ensure what you have originally is star/delta and not a 2 speed arrangement or even forward reverse set-up.. their are so many motor variations and control that often even the knowledgeable get confused.

Id also identify the motor and check for a plate - this will be a big clue to how it may have worked, and Im also betting if the controls were in such a poor state of repair then the motor will probably need testing long before any voltage is applied, if its been sat for several yrs depending on the environment it may be the case its sha**ed.

Check out Tony's PM as well if you already haven't.
PS - he's an old grumpy bugger but has a wealth of information even i admire ;)
 
Well its defo star delta, Quite a large portion of the system was replaced by the other guys last week.
New motor (old one was well and truly kaput!) , New Isolator, New collet, new phase cables etc. They only found this bit ime on now was cream crackered when it blew up in one of their faces!
So hence the now replacement of contactors etc etc.
I think originally everyone thought it would be a straight forward repair but its turning into somewhat of a mission!

I think the gaffa may well ask me to just get it going, Which is fine I can easily get it going star delta on a regular start/stop circuit but of course that then completely cuts out and safety circuits, temp control etc etc.

I never seem to get easy things to cut my teeth on.... LOL
 
Well the plot has thickened but I have made some head way into this mystery. (Kinda)....

So i have continued my cable tracing this morning and found one of the aux contacts on the delta to be connected to a supposedly unused and unworking speed control.
We all thought it odd it had speed control as there was no inverter etc on the motor but as it had never worked didnt care.
Anyhow after finding it is connected I decided to power up the control circuit and try it.

So i press start the star and main contactor pull in as normal then sat there like it has been.
Next i operate the speed control switch, both contactors drop out and the delta pulls in!!

Yay ive found another fault and probably the reason for the damaged equipment!!

So i have now come to the conclusion that my suspicions were right and this has been bodged n butchered so i have asked my gaffa to get a controls engineer in here to help me with this.

If it was straight forward star delta ide sort it myself but i know with the 11 unknown relays and 4 timers thrown in the mix its going to end in tears or my sack so think ime calling it quits here lol
 
Well the plot has thickened but I have made some head way into this mystery. (Kinda)....

So i have continued my cable tracing this morning and found one of the aux contacts on the delta to be connected to a supposedly unused and unworking speed control.
We all thought it odd it had speed control as there was no inverter etc on the motor but as it had never worked didnt care.
Anyhow after finding it is connected I decided to power up the control circuit and try it.

So i press start the star and main contactor pull in as normal then sat there like it has been.
Next i operate the speed control switch, both contactors drop out and the delta pulls in!!

Yay ive found another fault and probably the reason for the damaged equipment!!

So i have now come to the conclusion that my suspicions were right and this has been bodged n butchered so i have asked my gaffa to get a controls engineer in here to help me with this.

If it was straight forward star delta ide sort it myself but i know with the 11 unknown relays and 4 timers thrown in the mix its going to end in tears or my sack so think ime calling it quits here lol

If you produce a rough drawing, PM it me and I will give it a look over for you.
 
If you've not much experience in drawing out panels, considering this isn't very big. Your better just producing a point to point list, then producing a drawing from that.

This way is a piece of cake when cores are marked up properly, however I can't imagine your panels are.
 
You would be right there rob lol
Some are numbered correctly, some not, and some not at all.

Ime in the process of drawing out a very rough circuit diagram which is slowly painting a picture but still much to draw out and its getting increasingly messier and harder to read!!
 
Well the plot has thickened but I have made some head way into this mystery. (Kinda)....

So i have continued my cable tracing this morning and found one of the aux contacts on the delta to be connected to a supposedly unused and unworking speed control.
We all thought it odd it had speed control as there was no inverter etc on the motor but as it had never worked didnt care.
Anyhow after finding it is connected I decided to power up the control circuit and try it.

So i press start the star and main contactor pull in as normal then sat there like it has been.
Next i operate the speed control switch, both contactors drop out and the delta pulls in!!

Yay ive found another fault and probably the reason for the damaged equipment!!

So i have now come to the conclusion that my suspicions were right and this has been bodged n butchered so i have asked my gaffa to get a controls engineer in here to help me with this.

If it was straight forward star delta ide sort it myself but i know with the 11 unknown relays and 4 timers thrown in the mix its going to end in tears or my sack so think ime calling it quits here lol


The assumption we all are making is this is a Star/Delta starter but as you drip feed me info its sounding more like a control for a 2 speed motor which can be easily mistaken for a star delta arrangement if you are not accustomed to it... can you take a photo of the motor ratings plate ... that should reveal which it is, either that or its a manual star/delta changeover found on older systems ...need alot more info but if with our aid you can at least identify it it will be big brownie points when the sparks/engineers get back.
 
I think from what I'm hearing that actually getting the Y-D starter running is the least of your worries. You need to figure out exactly what the original design was when it was installed. This fan could be control interlocked with one or more other control systems and you need a complete overview of the local control and it's integration with other remote systems. If this fan is part of a building pressurization system for example then incorrect interlocking and integration could cost lives.

My advice is to get help from someone who's capable of signing off the entire system when it's complete. In a nutshell, two words; cover yourself.
 
Cheers Marvo, Like I said above I think this Job has been taken way out of my comfort zone now and become over complex for my limitations and knowledge.
It started as a straight forward part swap and has now turned into a mass scale controls nightmare!
And thanks to some insight and ideas from darkwood may not even be what we originally thought it to be.

So as they say on the den "ime out"

But I will keep you all updated on what the outcome is once it has been decided upon LOL
 

Reply to Star Delta starters and timers.... in the Commercial Electrical Advice area at ElectriciansForums.net

Similar Threads

Hi Changing a 3 phase star delta motor and replacing with a dol 3 phase motor. Would i be right in thinking I can remove 3 of the 6 cables at...
Replies
3
Views
1K
Heeelp! I have an 11kW/21A motor which is attached to a hydraulic power pack. I have replaced the old panels with new, using the same star delta...
Replies
17
Views
2K
Hi there, I got a call to a job, table saw (wood) tripping C/B straight away. 4kW motor on Star Delta Starter. So I get to the job, after some...
Replies
2
Views
3K
Hi I got called out to a faulty star delta starter on an old Stenner band saw Monday (was getting stuck in star and blow fuses) - So I ordered a...
Replies
19
Views
5K
We have this Swiss-made Dixi horizontal borer from 1957, very nice machine still with its original DC variable voltage drive. In those days there...
Replies
9
Views
2K

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock