Sizing Problem for DC Power Plugs

[Alan_C]

Hi all, a new member and here's my first question for you. The power cable on my Dell laptop has developed an intermittent break in the cable between the power supply (Type PA16, 19V DC output) and the laptop itself at the point where it enters the plug which connects at the rear of the laptop (Inspiron 2200). A new AC adaptor etc will cost $33, but a new plug might be only about £2, if I can work out what I need! The question is, how are they designated? I have seen descriptions like the following:

3 x 1mm hollow C
5 x 2.1mm hollow D
5.5 x 2.1mm hollow E
5 x 2.5mm hollow F
5.5 x 2.5mm hollow G
3.5 x 1.35mm hollow H
4 x 1.7mm hollow I
4.75 x 1.75mm hollow J
5 x 1.5mm hollow M
5.5 x 1.5mm hollow N
5.5 x 2.8mm hollow P

(see e.g. Maplin: http://www.maplin.co.uk/Module.aspx...&C=EBook&U=Ecat)

...and as you can see there is a wide variety of different sizes. If I rely on making measurements from my plug, I might measure the wrong place, or I might measure inaccurately. Does anyone know the correct part for my Dell, or eaxctly how it is measured / defined?

Thanks for any suggestions,
Alan

[DanU]

The first number is the outer diameter of the metal portion of the plug. The second number is the inner diameter of the "hollowed out" area of the plug.

[Alan_C]

DanU, thanks for that. I make it 6mm / 3mm; so it could be either 6.5/3.1 or 5.5/2.8! I guess I need a more accurate way of measuring.