Hi I’m clint

[Clintrose123]

Hi I’m Clint.

im new to this forum, I currently study electrical at college and am 4 months into my 1st year 

 

[Evans Electric]

Hi  Clint ,   welcome to the Forum .

How's the first year at college going ?     Have you managed to get an apprenticeship with a company  ?

 

[Doc Hudson]

Hi I’m Clint.

im new to this forum, I currently study electrical at college and am 4 months into my 1st year 

Welcome to the forum Clint, 4 months into your 1st year? That sounds as though you are adopting a sensible approach to attaining electrical qualifications,  i.e. a proper full college course. If you had opted for a 5WW short course, you would have finished about two and half months ago with "Full DI qualifications", {probably including PAT}" and be out there earning £80,000 p/a with a fleet of vans, one for each day of the week. So they say!

Just to advise, if/when you find you are struggling with a college question or understanding about some part of the wiring regulations, Don't hesitate to ask on here for advice. But, do make sure you offer your suggestion as to what you think the answer should be first.  As we are not a homework answering service, And most members are willing to offer advice and help, but it is an enormous help when wording our answers if we understand what your current level of knowledge is to start with. 

Doc H 

 

[Clintrose123]

Welcome to the forum Clint, 4 months into your 1st year? That sounds as though you are adopting a sensible approach to attaining electrical qualifications,  i.e. a proper full college course. If you had opted for a 5WW short course, you would have finished about two and half months ago with "Full DI qualifications", {probably including PAT}" and be out there earning £80,000 p/a with a fleet of vans, one for each day of the week. So they say!

Just to advise, if/when you find you are struggling with a college question or understanding about some part of the wiring regulations, Don't hesitate to ask on here for advice. But, do make sure you offer your suggestion as to what you think the answer should be first.  As we are not a homework answering service, And most members are willing to offer advice and help, but it is an enormous help when wording our answers if we understand what your current level of knowledge is to start with. 

Doc H 

Sorry for the delay in getting back in touch, also thank you for your reply!

Yeah im doing a proper course at college. I’ve been told by my tutor that my next assignment will be about contactors and what they can do.

i have a had a brief look at these now and already under it is some sort of magnetic switch which given power from between 12v-230v it then closes the contact and in return gives power to what you have connected to the contactor? 

I dont understand how these can help when you have big lighting loads? How would these be used on shop lights ? 

I want to try get my knowledge up on these before my new assignment to help myself ! 

 

[Tony S]

Have a look in "knowledgebase" on this forum.

 

[Doc Hudson]

Sorry for the delay in getting back in touch, also thank you for your reply!

Yeah im doing a proper course at college. I’ve been told by my tutor that my next assignment will be about contactors and what they can do.

i have a had a brief look at these now and already under it is some sort of magnetic switch which given power from between 12v-230v it then closes the contact and in return gives power to what you have connected to the contactor? 

I dont understand how these can help when you have big lighting loads? How would these be used on shop lights ? 

I want to try get my knowledge up on these before my new assignment to help myself ! 

Have you ever looked really close at a typical light switch in your home, especially some of these modern budget brands with very thin plastic construction? And if they are still operating traditional non-energy saving lamps, you will often see a, (sometimes quite significant), spark as the contacts break and make while turning the load off/on. You have to remember a basic principal that all switches have to be mechanically robust enough to withstand any arcing and sparking that occurs as they operate turning loads on/off. To have switches robust enough for larger loads, so the contacts don't burn themselves out or weld themselves together, would mean the physical switch needs to be too large to be accommodated at the location where they need to be controlled from, and would certainly need a bit more physical effort to manually operate.

Are you familiar with how relays are used in automotive wiring so that very delicate finger touch switches can turn on larger loads? i.e. dashboard or steering stalk switch operates a relay needing very small current, and the relay using a magnetic coil can pull a pair of larger high power contacts, that can turn on all sorts of accessories e.g. heated rear window.

So what do you think a contactor can do with mains voltage loads and how is the contactor operated.   

Doc H.

 

[Evans Electric]

Look at it like this Clint ,  I used to do a lot of Barclays Banks ,   many of them had a small key  switch  or button at the final exit  that worked a fairly big contactor  .   The contactor turned off all the lights & sockets  etc except the necessary  stuff .     So you didn't have to your the building  every night , switching stuff off everywhere.    Some areas would be  secure so you couldn't get in anyway .  

You can't switch all that stuff off with one little 5A switch at the door..     the 5A  switches the contactor ,   the contactor  switches the loads .     

 

[Clintrose123]

Have you ever looked really close at a typical light switch in your home, especially some of these modern budget brands with very thin plastic construction? And if they are still operating traditional non-energy saving lamps, you will often see a, (sometimes quite significant), spark as the contacts break and make while turning the load off/on. You have to remember a basic principal that all switches have to be mechanically robust enough to withstand any arcing and sparking that occurs as they operate turning loads on/off. To have switches robust enough for larger loads, so the contacts don't burn themselves out or weld themselves together, would mean the physical switch needs to be too large to be accommodated at the location where they need to be controlled from, and would certainly need a bit more physical effort to manually operate.

Are you familiar with how relays are used in automotive wiring so that very delicate finger touch switches can turn on larger loads? i.e. dashboard or steering stalk switch operates a relay needing very small current, and the relay using a magnetic coil can pull a pair of larger high power contacts, that can turn on all sorts of accessories e.g. heated rear window.

So what do you think a contactor can do with mains voltage loads and how is the contactor operated.   

Doc H.

Thanks again for anothe reply, I haven’t really looked up much about relays but I think I will try look this up. Still trying to get my head around these contactors, i think I’m over thinking a lot into it and it’s beginning to confuse me. 

Do you have any material which would help me get a better understanding?

Look at it like this Clint ,  I used to do a lot of Barclays Banks ,   many of them had a small key  switch  or button at the final exit  that worked a fairly big contactor  .   The contactor turned off all the lights & sockets  etc except the necessary  stuff .     So you didn't have to your the building  every night , switching stuff off everywhere.    Some areas would be  secure so you couldn't get in anyway .  

You can't switch all that stuff off with one little 5A switch at the door..     the 5A  switches the contactor ,   the contactor  switches the loads .     

Thank you for the reply, am I to believe that this “big contactor” would be fed from a dB which could potentially take upto 40amps to help hold all this load of lights? 

You also speak of a last man switch so everything is turned off but not taking all the load, am I to be believe this could be wired in 1.5mm T&E back to the contactor which would connect to A1? Which is the live to the coil which would then open then contact, killing all the power to these lights?

please tell me if I have gone off topic and if I have it wrong any corrections to the right direction would be great.

thank you all

 

[Evans Electric]

ou also speak of a last man switch so everything is turned off but not taking all the load, am I to be believe this could be wired in 1.5mm T&E back to the contactor which would connect to A1? Which is the live to the coil which would then open then contact, killing all the power to these lights?

please tell me if I have gone off topic and if I have it wrong any corrections to the right direction would be great.

I think thats what I just said . 

 

[Clintrose123]

I think thats what I just said . 

Sorry 

I guess my only input in what you said to me was, would the 1.5mm from the main cut out switch to the contactor be connected to A1? 

my next questions, would you just take all your switch wires back to this contactor? If so, how would these be able to be independently switched ie, if the customer wanted the staircase lights to have its own switch, but also switched off from this main switch at night . 

Also, if you had a 40amp contactor, would the load whichh you wire into these (lights) need to have CSA adequate enough to carry 40 amp?

 

[Evans Electric]

The coil that operates the contactor is across a1 & a2   . Its voltage could be anything from 12  - 24-  50 - 110 -  240 -  415 V .

The usual way to do what I described would be to  switch the power to a non - essential  Dist.Bd.   

 

[Clintrose123]

The coil that operates the contactor is across a1 & a2   . Its voltage could be anything from 12  - 24-  50 - 110 -  240 -  415 V .

The usual way to do what I described would be to  switch the power to a non - essential  Dist.Bd.   

So I’ve been going through some of my stuff with my college tutor today and praised me for going out looking for this information before the assignment has started.

He said I’ve got the understanding of the contactor, but he thinks I’m getting lost when it’s coming to doing the switching of things

do do you have anything that I can read upon this to help grasp this?

also, you said “to switch the power to a non - essential Dist.Bd” 

can you draw this out to see see if I understand it better? 

If not it’s fine, I appreciate the responses 

 

[Evans Electric]

There you are Clint  ,  any more homework you'll  have to do yourself mate  

 

[kerching]

Deke.....which CAD program are you using?

 

[Clintrose123]

There you are Clint  ,  any more homework you'll  have to do yourself mate  

View attachment 9881

Hehe, I honestly can’t thank you enough. 

I understand now a lot better. I had pictured all so differently in my head. I assume the little symbol which you have taken off one of the phases is a breaker? 

Once again thank you!

Dont worry I won’t use this to take credit from my tutor  

 

[Evans Electric]

Deke.....which CAD program are you using?

Its a new one Kerch  , very technical ,  you wouldn't understand  , you have to be an IT officianado  like myself  ...its called  A4 &  pencil    :innocent  

 

[Evans Electric]

Dont worry I won’t use this to take credit from my tutor  

No probs  Clint .    Everyone on here will help  with general electrical  questions  etc,     but  there,s a few who try to get each weeks homework  / college work  done , which doesn't help anyone TBH.     

 

[Clintrose123]

No probs  Clint .    Everyone on here will help  with general electrical  questions  etc,     but  there,s a few who try to get each weeks homework  / college work  done , which doesn't help anyone TBH.     

That’s good to know, an nah I’d rather ask the questions and get the understanding through that way. As I’m only going to cheat myself! 

Do you know any website which has good revision material which would be of good use to me?

 

[Evans Electric]

Someone will  ,  keep looking ..... dinosaurs were roaming  outside the college when I was there last . 

 

[kerching]

Its a new one Kerch  , very technical ,  you wouldn't understand  , you have to be an IT officianado  like myself  ...its called  A4 &  pencil    :innocent  

I thought I recognised it

HB Staedtler BASIC i think