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Test 1B Testing - Continuity of Protective Conductors:

Description of test

Performing this test is to ensure that there is continuity throughout the circuit, that there are no breakages and conductors have been connected correctly. Be sure you have isolated the supply before beginning the test.

Methods

Test method 1 : Short lead Test

Test method 2 : Long lead Test

Test Equipment

Low Ohm Resistance Meter

Note: R1 = Resistance of Line conductor, R2 = Resistance of CPC, Rn = Resistance of Neutral

Test Method 1: Short Lead Test

A Typical example would be to cross connect the Line and Cpc conductors at the distribution board of the circuit going to be tested. At each point of the circuit, at test between Line & Cpc should be performed. Noting that as you perform the tests further away from the cross connected ends at the distribution board, the higher the reading will become. The result recording the highest reading will be the R1 + R2 value on the test sheets. Make sure the test leads have been nulled on the tester or subtracted from the results accordingly

Test Method 2: Long Lead Test

This test is slightly different to method 1, as you are only testing the Cpc. It is known as a long lead test because you may have to use an extra long cable to reach both ends of the Cpc. (Twin+earth can be used to create an extra long test lead). Making sure you null out the test leads before the test.

So basically what you have is your test meter connected to the Cpc at the distribution board and the other (extra long test lead, if necessary) test lead connected to the other end of the circuit. Perform the test, and record the highest result as the R2 value.

Posted by admin Posted in: Test 1B Testing - Continuity of Protective Conductors: No Comments » April 2008

rcd main switch + mcbs (non split Board)

Having a Consumer Unit with an rcd as a main switch and just mcbs, not on a split board contravenes the regulations in the 17th edtion under reg, 314.1 (see also 314.2)

An Rcd as a main switch when tripped due to the failure of a circuit or due to nuisance tripping will affect all other circuits wont it

Posted by admin Posted in: Electrical stuff cant see it? No Comments » April 2008

Steel Armoured Cable info

Hello, just a little information about Steel Armoured Cable (SWA)

Steel Armoured Cable is protected by a sheath of galvanised steel. This makes it suitable for direct burial, cable ducting or it can be surfaced mounted without any further protection. It can be used for indoors and outdoors.

Steel Armoured Cable (SWA) Cores Colours

2 core = Brown/Blue
3 core = Brown/Black/Grey
4 core = Blue/Brown/Black/Grey
5 core = Green-Yellow/ Blue/Brown/Black/Grey
Alternative core colour - Black numbered

This is a great website which shows you how to make off a steel armoured cable. There are 3 steps shown on this website, very clear and detailed.

Step1:

Step2:

Step3:

Average Prices (taken from www.screwfix.com on 26/10/07)

6943 X 2.5mm 3 core SWA Cable 25m £31.42

6943 X 4.0mm 3 core SWA Cable 25m £39.94

6944 X 1.5mm 4 core SWA Cable 25m £34.97

6944 X 2.5mm 4 core SWA Cable 25m £44.25

6944 X 4.0mm 4 core SWA Cable 25m £51.95

Posted by admin Posted in: Steel Armoured Cable No Comments » April 2008

IP (ingress protection) Rating

First Number	Meaning	Second Number	Meaning
Refers to protection against solids		Refers to protection against liquids
0	No protection	0	No protection
1	Protected against solid objects over 50mm (e.g. accidental touch by the hand)	1	Protected against water falling vertically
2	Protected against solid objects over 12mm (e.g. accidental touch by the finger)	2	Protected against direct sprays from up to 15 degrees from vertical
3	Protected against solid objects over 2.5mm (e.g tools, wires)	3	Protected against direct sprays up to 60 degrees from vertical
4	Protected against solid objects over 1mm (e.g. small wires)	4	Protected against sprays from all directions. Limited ingress permitted.
5	Protected against dust – limited ingress (no harmful deposit)	5	Protected against low pressure jets of water from all directions. Limited ingress permitted.
6	Totally protected against all dust	6	Protected against strong jets of water. Limited ingress permitted. E.g. acceptable for use on shipdecks.
		7	Protected against temporary affects of immersion between 15cm and 1m, for 30 minutes.
		8	Protected against long periods of immersion under pressure.

Posted by admin Posted in: Ingress Protection (IP ratings) No Comments » April 2008

test

Posted by admin Posted in: Emergency lighting, intermediate switching No Comments » April 2008

Test

Posted by admin Posted in: 2377 Papers, 2381 Papers, 2382 Papers, 2391 Papers, 2392 Papers, 2393 Papers No Comments » April 2008

wow arent they amazin

Posted by admin Posted in: Makita No Comments » April 2008

1 way switching

This is going to explain how to deal with 1 way switching

Posted by admin Posted in: 1 way switching No Comments » April 2008

2 way lighting

Here we’ll explain how to do 2 way lighting

o———o 0—————-0

0—————————o

The diagram shows single colours only. In real life these wires would be covered by an outer protective sheath and would include a bare earth wire and would be called a cable.

Red sleeving or tape would of been placed on the wires as shown to show that they would be live at some point. Now this sleeving would be brown.

The connections are very simple and there is another guide further down this page.

Posted by admin Posted in: 2 way switching No Comments » April 2008

here are a list of the avalible papers which you can obtain at your leasuire

here is a testing one: