practical exam theory
#271
Just Joined
Joined: Nov 2013
Posts: 7
Re: practical exam theory
hi all,
from the drawing that dune put up where would you wire the emergency stop and are them 2 drawings all they are after or is more needed, any help appreciated thanks
from the drawing that dune put up where would you wire the emergency stop and are them 2 drawings all they are after or is more needed, any help appreciated thanks
#272
Just Joined
Joined: Sep 2013
Posts: 27
Re: practical exam theory
Ye mine all done . Exam not to bad . Learn your power formulas and ohms law v= I x r etc. they ask health and safety and basic scenarios that any sparky should know. I had a question to work out current carrying capacity and voltdrop. Resistors in parallel and series. The dol starter they ask you to draw a diagram for the control and power circuit . Then u have wire it up. The one we had was like the ones you buy in the wholesaler with the start and stop button one it . It's basically mounted on the wall and u have to wire it and add a emergancy stop to it. The em stop button is mounted on the wall next to the dol . Just make sure once it all wired that hold on contact (13+14) is wired in parallel to the start button or else the motor won't start and run. Everyone got stuck on that . But the guy lets u try till u get it right in ur time frame obviously . They very helpful. If u follow ur diagram u will be fine. I had a 3 phase contactor with a 3 phase coil. R u doing urs with future skills? Mine was in Tottenham London .
#273
Just Joined
Joined: Sep 2013
Posts: 27
Re: practical exam theory
Ye mine all done . Exam not to bad . Learn your power formulas and ohms law v= I x r etc. they ask health and safety and basic scenarios that any sparky should know. I had a question to work out current carrying capacity and voltdrop. Resistors in parallel and series. The dol starter they ask you to draw a diagram for the control and power circuit . Then u have wire it up. The one we had was like the ones you buy in the wholesaler with the start and stop button one it . It's basically mounted on the wall and u have to wire it and add a emergancy stop to it. The em stop button is mounted on the wall next to the dol . Just make sure once it all wired that hold on contact (13+14) is wired in parallel to the start button or else the motor won't start and run. Everyone got stuck on that . But the guy lets u try till u get it right in ur time frame obviously . They very helpful. If u follow ur diagram u will be fine. I had a 3 phase contactor with a 3 phase coil. R u doing urs with future skills? Mine was in Tottenham London .
This applys to a bog standard dol starter that u buy from the wholesaler. The only thing with those is that the 96 terminal in already internal linked to A2. Try get ur hands on one of them and a em stop button, wire it up and see if works . Then u should be fine.
#276
Just Joined
Joined: Nov 2013
Posts: 7
Re: practical exam theory
hi,
well done for passing exam, cheers for that info earlier but to be honest im still struggling with it all, do u have or know where i can get any drawings for the power and control circuits with an em stop so i can get my head round it.
cheers
well done for passing exam, cheers for that info earlier but to be honest im still struggling with it all, do u have or know where i can get any drawings for the power and control circuits with an em stop so i can get my head round it.
cheers
#277
Just Joined
Joined: Sep 2013
Posts: 27
Re: practical exam theory
Hi mate. If go to page 15 of this thread there some links to loads of usefull info on dol starters some one put up. Explains exactly how it works and drawings.
#278
Just Joined
Joined: Sep 2013
Posts: 27
Re: practical exam theory
Drawings I used. Just remember if there's no neutral for the power circuit use a another phase for A1 providing its a 3 phase coil.
#281
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Joined: Sep 2013
Posts: 27
Re: practical exam theory
U can also buy a book on e bay called electrical calculations by aj Watkins for bout £12 . Really helpful for the theory. .
#282
Just Joined
Joined: Nov 2013
Posts: 7
Re: practical exam theory
hi,
ye thanks for that helped a great deal things are starting to click now cheers, any other tips for the theory or other parts of exam cheers mate
ye thanks for that helped a great deal things are starting to click now cheers, any other tips for the theory or other parts of exam cheers mate