Din rail timer

[Octopus]

Another bulls eye.

Actually this job is for my assessment.

Although I am not sure which scheme to join yet.

The weather proof box is attached to the garage CU which itself is attached to a 32 Amp MCB in the main house so I am basically extending a radial not creating a new circuit, well that's how I see it.

So are you thinking that adding a new radial is different from adding a circuit. I don't think so.

 

[La Poste]

Well if you have a circuit from the house fused at 32 Amps and you were to say add a fused connection unit to it as a spur then would that be adding a new circuit?

In this particular instance the cable runs from the house and is fused at 32 Amps, the cable was already in the garage.

So what's the difference between adding a fused connection unit and a spur or adding an MCB and then a spur?

If you see what I am getting at.

P.S. I got a din rail timer really cheap, a fiver as it was old stock with no instruction manual.
Only 2 Amps inductive load so it can't carry much but it's OK for Christmas lights.

Also I might go with Stroma for my first year as they only cost £250.

And if anyone is concerned about me doing work outside of part P then my assessment job was designed and built by me under the very watchful eye of my NICEIC Boss.

I had to figure it all out and he would say if wrong or right.
Effectively I did it as his employee but he will allow me to use it at my assessment.

I have to do all the paperwork and tests, load calculations, diversity, cable installation methods etc myself and then convince the assessor I am competent.

Although from what I am hearing by approaching some of these Part P bodies, I do not have to know very much to be welcomed on board.

 

[mechelec]

In answer to the OP original question the switch is derated for inductive loads because when the current flowing through an inductor i.e. relay, ballast ect is interrupted by opening the controlling switch i.e. the timer contacts , a transient self-induced voltage is produced. The magnitude of the switching transient is primarily determined by
(a) the strength of the magnetic field at the moment of switching,
(b) the time rate of decay of the field, and
(c) the resistance of the circuit across which the reverse polarity potentials
induced by field decay appear.
This produces an arc across the contacts that causes erosion and reduced working life.
It is not the inrush current when closing of the switch on to an inductive load that causes a problem it is the opening. It can be mitigated by insalling an RC network accross the switch contacts.

 

[La Poste]

Thanks that makes a lot of sense.

Would transformers used to supply low voltage lighting be classed as inductive loads?

When you switch the lights off at the switch is there an arc?

 

[PC Electrics]

If you've added a new MCB to a CU (even if it is a sub board) to supply a set of sockets (or a weatherbox in this case), then you have added a new circuit and it is notifiable as such. It is also notifiable because it is outdoor power.

If you think otherwise, then good luck at your assessment. You're gonna need it.

As for not needing to know much to be welcomed on board - well, not a good attitude is it? Also, don't believe everything you read. Many 'proper sparks' on here and elsewhere have a huge chip on their shoulder about 'retrainers' and all sorts of prejudice gets spouted. All schemes can and do fail those who they feel are not competent at initial (and subsequent) assessment.

May I suggest Approved Document P as a piece of relevant reading.

Why not use a simple mechanical immersion timer?

 

[La Poste]

Many 'proper sparks' on here and elsewhere have a huge chip on their shoulder about 'retrainers' and all sorts of prejudice gets spouted.

To be honest I have found most people on here very helpful.
And anyway, the sort of work I will be doing and the amount of time it takes me to complete it will not be affecting anyone locally, work wise I mean.

I work really slowly and am part time, I work most weekends with my NIC boss more as a labourer than anything else, chopping out etc and I have been doing this for over three years. When I am part P registered I will probably only do three or four jobs a year so it won't amount to much.

That's why I am interested in the cheapest scheme provider, because of the small amount of jobs I will be doing.

 

[Octopus]

Hum, 3 or 4 jobs per year.

Membership costs, PL insurance, calibration of test kit, as its a 2nd job so 28% tax and NI on every pound you earn.

Doesn't make commercial sense to me.

 

[La Poste]

Tax?
I do all these jobs for free.
I don't charge.

It's just to gain experience.
Let's just say I like to keep busy and keep learning for when the Post office finally goes t1ts up.

Then maybe I will go full time, right now this is my apprenticeship so I don't expect to earn much.
At the moment I basically work for fk all.
It's not perfect but then in a world with no apprenticeships this is as good at it's gonna get for me.

I got my 2391 in August, passed first time.
Thanks mainly to this site, IQ electrical and Bruce Lee spring to mind, they were both brilliant.

Maybe the cost of exams can be off set against any earnings I will receive.
I'd rather spend it this way than pay the tax man so he can have cosy relationships with big business letting them off millions while he crucifies the likes of me.

Yes, definitely, any earnings I receive will be spent on courses and/or tools thus providing me with zero profit.