How to read electrical drawings (i can't)

[Darkwood]

You clearly work for a company who design and provide their own schematics, I would try get a 20min chat with one of the designers and he should be able to point you in the right direction as to page numbering sets and codes... usually the schematics are layed on a grid format (grid may be shown or not but the edge references will be)and when a wire exits a page it will have a page reference and grid/column number so you can jump straight to the line you are following.

 

[Shaun12]

yeah you're correct. Although i'm out on site al day so driving to the office to speak to someone in design isn't really a possibility.

This thread is exactly what i'm talking about

http://www.electriciansforums.co.uk/commercial-industrial-electrical/53115-electrical-diagrams.html

So in that drawing the contactor in question is 20Q1? The terminals are the numbers 1-3-5 (top) and 2-4-6 (on the bottom) will these numbers be on the actual contactor or is it just a reference for something on the drawing? 22/33 would be aux contacts?

I find this stuff so much more interesting than bending conduit and fixing panels to the wall. i'm really keen to learn this

 

[Darkwood]

yeah you're correct. Although i'm out on site al day so driving to the office to speak to someone in design isn't really a possibility.

This thread is exactly what i'm talking about

http://www.electriciansforums.co.uk/commercial-industrial-electrical/53115-electrical-diagrams.html

So in that drawing the contactor in question is 20Q1? The terminals are the numbers 1-3-5 (top) and 2-4-6 (on the bottom) will these numbers be on the actual contactor or is it just a reference for something on the drawing? 22/33 would be aux contacts?

I find this stuff so much more interesting than bending conduit and fixing panels to the wall. i'm really keen to learn this

They are one variant you may find on the contactors likewise it may say L1 L2 L3 etc just look up contactor pics and see the different ways manufcturers label the terminals but 1-3-5, 2-4-6 is a recognised format... although this is ident of device only, the cables will have most likely other numbering systems that connect to them so its recognising what is what really.


20Q1 looks like a overload trip device for a motor
the K1 and K2 devices are contactors possibly forward and reverse options

 

[edexlab]

This is an American article so some symbols do differ slightly but I found it useful to start reading ladder diagrams


https://www.google.de/url?sa=t&sour...TOWAeQ&usg=AFQjCNHbvyerMSdyEaWPR5AwO8ZGNOFYUw

 

[Shaun12]

Hi thanks for the link, it doesn't seem to work for me, could you possibly try again so i can have a look? I'm actually quite handy with ladder logic/ PLC's and programming..

 

[edexlab]

I've just tried it and your right it's not working , I just typed in
"reading electrical ladder drawings " to Google and this was an article for

"m ecmweb.com>Basics "

It just shows/explains the format or layout of a ladder diagram ie input/ output devices positions rungs and numbering ,Nc/No contacts might be too basic for you perhaps

 

[Shaun12]

oh ok. What I'm going to do is get some drawings from work and anything i'm not sure of ask here. I'm sure it will help others as well

 

[Spoon]

oh ok. What I'm going to do is get some drawings from work and anything i'm not sure of ask here. I'm sure it will help others as well

Good idea.

 

[edexlab]

I'm in the same sort of situation , although I do work in the factory as well as on site, the company here likes you to learn off your own back so I started looking at the drawings doing some research online and trying to figure out what's what,
their drawings are a bit different from conventional drawings and people here are not always forthcoming with information, some are good, but I don’t see them much
but the overall culture is to find out yourself !

The best thing I've done to improve my understanding was to take the drg and trace it through panels referencing the control drgs ( during my lunch ) starting from the incoming isolator all the way through

This made it all make much more sense!

Then I got lucky and got the chance to work on a machine with an engineer

I had to trace through all the circuits and check them against the drawing removing any unecessary modifications (machine was an experimental ) and then redoing it to his design.... this was a really good experience tbh and I feel I'm getting somewhere now