Probably more of a maths problem than anything else / managing to confuse myself.
I have been asked to look at energy consumption of some temporary units. They're all electrically heated office style temporary buildings. Keeping it simple, at the origin of supply there's 3x 63a MCB's feeding...
Im currently in my apprenticeship and completing an assignment that involves cable calculations. Im currently stuck on how to find the design current for my socket circuit that has an unkown load. Do i just use the on site guide or is there a calculation i can do ?
Got my am2 coming up on Tuesday and I know I have to calculate my Zs readings
Maybe I’m overthinking this but am not sure if I need to use the Ze (which is apparently given to me) or my measured Zdb from my three phase panel in the equation. I have heard different answers, would be great if...
hi in college and watched some YouTube videos and read up on things I think I got the right formula but I'm not sure.
Zsc= Zesc(or Zdbsc) + (R1+RN)
(R1+RN) = milli ohms/metre x length x correction factor and then divide that by 1000
Zesc = Uo divided by PFC
Then add together Zesc and (R1+RN)...
Hi all, just a quick query really.
I'm and apprentice on me second year and currently doing my design project and confused about length of run per circuit.
I know you can't exceed 30m per circuit but what about lighting? Does this include separate switches? Like can I power one grid switch...
how to calculate the needed power to light up 6 cool white and 6 white HPL chip like this ?
what is the compatible driver specifics to light up 6 cool white and 6 white HPL chip like this ?
My brain has been exercised a bit by this. Am I on the right lines with this extremely simplified example:
If we take:
-TNCS installation with a Ze of 0.2 ohms.
-Plastic services, nothing bonded, keeping it simple
-Line conductor resistance from supply transformer should be similar to PEFC and...
I'm getting a little confused about volt drop and 24v.
I want to fit an LED strip light. 8m of lights 7w/m.
It would be easier to have the 24v driver approx 10m from the beginning of the strip of the LED strip.
I'm not sure where to start to know if this will work without any effect on the...
Hello I'm an apprentice looking for tips and techniques. I asked this question before but got no response.
When it comes to installing downlights what is your method for how many downlights you require?
Do you do the lumen calculation or are there other quick ways to do it.
Thanks.
I need to, as accurately as possible, establish what the inrush current is for some large metal halide floodlights with magnetic ballasts and I'm drawing a blank.
This is for a switchgear/DB replacement I am in the planning stages of and need to know whether these circuits can be fed from MCBs...
Ok.
I've fitted 2 tone car horns in place of 1 tone horn on my Renault Kadjar. The factory horn is weak.
I'm attaching a photo of a waterproof scotchlok crimper connector which will connect 2 factory wires to new wires to horn. The car horn runs via 10 amp fuse.
My question is: does anybody...
Morning Again
In my last post I was asking whether to TT or not to TT and another question was posse by Strima saying that my allowance of 38 amps was possibly to much.
I'd based this on the fact that I only had a slight idea of what the customer was going to do in the shed/summer house. so...
Hi all,
quick question, hoping an easy one to answer. Just need to clarify this up in my own head.
When calculating fault current from Zs, do I take Cmin into account?
For example.
Zs is 0.54 ohms
So to find fault current I would calculate nominal voltage / Zs
So 230 / 0.54
But, should I...
How is voltage drop of a circuit normally calculated in the UK? And why are wires 16mm2 and under listed as a single unit, but 25mm2 and over in R, X and Z? How do I work with Z?
Hi guys,
I just need help with something really basic that I’m struggling with in terms of calculating resistance (as opposed to measuring).
Just a hypothetical question here, not a real situation, I just need to understand the theory.
If I had a socket, just 1, on a radial, running from DB...
When doing volt drop calcs, should you use the rating of the mcb/rcbo for the design current or the realistic current the circuit is going to use?
Just doing a calc for 40m or 4.0mm 3core swa feeding 6 sockets. Im going to wire them in a radial via b32 rcbo
Hello All,
Just a quick one. We look after a factory that has a 250amp busbar running around the factory. We have a machine plugged in with a 70mm 4 core swa and the ZS reading is too high so we are going to run in a separate earth to help, how would we determine the size needed to run in?
Thanks.
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