Electrical tips and tricks

Hello Everyone,

I am sorry for my lack of activity.  I went into a bit of a downer, after not getting a full time teaching job last year.  There is no point in crying ( boo, hoo!) as everyone is going through hard times at present.

I have now shaken myself down and am ready to re-contribute to the world of ‘all things electrical’

Now for this week’s news…… I am handing in my Cert-Ed paperwork on Thursday.  It is all complete after a two year slog!  This means I will be a qualified teacher very soon.  I have also started on a draft of my latest project.  I am going to dissect BS7671 to help all my disciples to pass the exam with ease…….

Bye for now!

Hello All!

Have been doing a little job at the British Legion today.  The club needs a Periodic Inspection so I am helping to make this happen.  I was working on the main distribution board and found something that may be of interest to the to the regular ‘Part P’er’ who doesn’t venture into factories and the like……

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Hello All!

A got a call out from a local church this week.  He was a little concerned with the heating.  He had to switch it on and off by going in here!

It is a sea of botched wiring and plug in timers-truly scary…..!  Anyways, he asked could I fix it and of course I said yes, with a sly gulp!  He wanted the three zones controlling on individual time clocks so I wandered off to the wholesalers!  This is how the job went….

First task was to identify and mark all these pyros.  Next I chiseled through the rusty screws and dropped the panel.  This system had stuff that the church had never used, like vent fans so they asked for it to be all disconnected. All they want is their three heating zones…..

That is more like it!  Notice this box is smaller than the old one. The conduit is now a little short so that was the next job!

Now this is a tool you just have to have!  This is a self levelling lazer.  You can see I have put a dot on the side of the adaptable box ready for the drill.  Just got to set the new conduit by 25mm and cut to length…..

Now we hit rough waters!  All the pyros coming in the top are easy peasy, but this is where I need to be careful!  Because the new box is smaller, these boiler pyros from the bottom are short! What I did was to re-bend them to make them shorter still and gland them off to a metal adaptable box.  Remember, these are old cables with no earth tail, like you see these days.  The earth continuity must be good and it is achieved via the gland.  Tightened up here now, all is well!  It was then a simple job of joining the boxes with a small piece of tube containing  pvc wiring including a cpc connected to the metal box. Here is a closer look…..

Note the cpc fitted.   Also see how I set the different length cables to reach the same spot.  Yes, nice but it could turn ugly if the cable now fails it’s insulation resistance test!  Of course I am kidding- it all tested OK after the fettling!  Notice I have fittted a small peice of ‘din rail’ in the back and fitted what are called ’sax terminals’ .  Makes a real neat job I feel.  Anyway, nearly there now!!!

Now I did cheat here as the lid bit, I did in the garage the day before- a bit like ‘blue peter’- remember that- “Here is one I prepared earlier”  I made up the front, more din rail and sax terminations.  The rail also carries the three relays I need to make this work.  I have terminated all the cables I need and loomed up all the spare ones at the top….That is us all done now….

And so, there we are!  I have put an isolator on the unit for good measure and marked it all up…… Now a brief explanation of how it works.  Basically the power comes into the isolator and then out to the clocks.  Each output from each clock runs it’s respective pump.  As well as running its pump to also feeds the energising terminal of it’s own relay.  The three relays are wired in a parallel  fashion so when the pump supply pulls it in the relay switches on the supply to the boiler.  That way any clock will switch on its pump and boiler without affecting the other zones……. clever eh!

Till next time, all the best!

Alan

Hello all!

I was back in Ireland last week on a family visit and just went round to look at my sisters mansion!  I will have to finish that first fix sometime- a good excuse for another visit me thinks!

Anyways a couple of pics for you peruse this week….. The first concerns the difference in Irish regulations to ours.  Check out my mothers consumer unit…….

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Hi Everyone,

Last week I dusted off the tools and went back over to my local Royal British Legion.  They are fed up with soaring electricity costs so asked me to put the toilet lighting on motion detectors.  It was nice little job so I took a few photos for you.

The first thing is SAFETY FIRST! Just because it isn’t school or you’ve been doing this for years you must follow your safe isolation procedure. I have pulled the fuse for the lights and checked for ‘dead’ there.  I am now back at the mains checking the lamp.  By the way I am in the building alone so not locking off the whole mains is not required, I am perfectly safe.

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Hello all,

I was teaching this week and the fire alarm guy was round servicing the big panel in the entrance hall.  The panel sits there with no wiring showing, so it must be wired from “round the back” so to speak continue

Hi All,

Now the title of this blog has your inquisitive juices flowing let us proceed with gusto!

I went over to Northern Ireland this week-end to visit an old school chum. On the day I was leaving I was stood outside a cafe in a little town and found something for you!  Firstly you may remember this……

For those from another planet or below 25 this is Hilda Ogden posing with a picture of her beloved Stan and her treasured flying duck mural in the background! So then how could I make the link in “busman’s holiday mode”……. continue

Hi All,

All of my career, so far, I have always been struck by the two distinct strands that exist in our field……

• Those that “write” about how to do it
• Those that actually “do” it

As you know I am a new writer and have set out on a one man mission to put all this nonsense right! Now the “Part P Doctor, Second Fix” has been safely launched I am trying to squeeze some time to do other books! My next project will be to show the rookie (or rusty pro) all I have learnt in 30 years on tips and tricks to do with installation.

As all my regular readers are aware I also do quite a lot of teaching these days which leads me on to this weeks blog.

The college, where I lecture have decided to launch a new short course called “The fundamentals of inspection and testing” which is also known as the 2392 ……… continue

Hello all,

When I was writing the new  ”The Part P Doctor” book, the project, as you know, revolved around the actual rewire of an old house.  The house in question was a large early 1930’s detached home.  It had been rewired in the past but as I was doing more work I stripped out these little gems to show you…...Lead, VIR and TRS Don’t worry if this is all double dutch, just carry on reading!

Starting at the top you can see lead covered twin cabling.  This went out of use in the 1940’s.  It consists of copper wire covered with tin, then rubber and finally a lead sheath.  This sheath was used as a cpc. Lead oxidizes very quickly, going black. However, I have scrapped a nice shiny bit for you in the picture.

Next down is old steel conduit with single wires fitted.  This was very popular in the 1930’s and 40’s.  The conduit is the cpc. The wires are called “Vulcanised Indian Rubber” wires.  Here, we have again tinned copper wires, rubber covered and topped off with a cloth tape or covering. Again, I have unwound a little of this to show you.

The last one is later again, perhaps up to the end of the 50’s.  It is called TRS which stands for “Tough Rubber Sheathed”.  Again, the wires are tinned copper but the cable is the same as you use today except you now use PVC instead of rubber.

I don’t know why they tinned the copper then but it must have had something to do with a reaction between copper and rubber.  All these old wiring systems had definite life spans for sure.  Th old rubber dries and crumbles away and insulation faults result!  My advice is to not touch anything that looks like this.  If you do disturb it and it all crumbles before your eyes, don’t say I didn’t warn you!  Finally, if you are just passing by this site and not an electrical person, do look out for this stuff in your home.  If you find it, please, please call out an electrician.  I am sure there are still many thousands of miles of this stuff lurking around out there!

The final question from customers and students alike is, “How long does PVC wiring last?”  Well, having worked in houses recently, built in the early 60’s I would say “forever!”  Remember the only thing that can kill PVC wiring is heat from bad connections or general overloading.

Bye for now……

Good evening all,
I was installing some “dado trunking” in an office recently and came across the dreaded ” not a 90 degree bend” scenario. You know how it works, they pre make 90 degree internal, external and flat bends but alas not say 135 degree ones! After I fitted the trunking, I set about trying to piece up the lid and that was when the fun started! Basically, it looked appalling!
So, it was time to think about it and then I had that eureka moment…..Here is how I did it.

I used a bit of geometry and eventually ended up here continue