Why do laptop PSU's now use a cloverleaf plug instead of a kettle plug?

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robocat

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#119097 20-May-2013 15:32

My google foo is failing me... There must be a reason for the change, but I can't find it!

Older laptop power supplies used the common PC "kettle" plug/socket (C13/C14) but newer ones seem to use the cloverleaf/mickey-mouse plug/socket (C5/C6 - http://en.wikipedia.org/wiki/IEC_60320 ).

Anyone know?

ubergeeknz

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#822487 20-May-2013 15:39

The rated current for the cloverleaf is 2.5A vs the IEC connector rated at 10A.

For one, there's probably less copper required to make the connector itself. Second, the lower current requirement should allow for the use of thinner cable.

robocat

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#822488 20-May-2013 15:43

Sooooo obvious - saves a few cents on copper (and I even inkled it might have something to do with current rating but me dummy didn't look at the correct column!).

Thanks heaps!

toyonut

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#822500 20-May-2013 15:53

I would say it is also more compact so saves some space on the adapter and allows it to be smaller and more travel ready.

Try Vultr using this link and get us both some credit:

http://www.vultr.com/?ref=7033587-3B

graemeh

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#822510 20-May-2013 16:18

I have a very old (approx 1997) laptop that used the "figure 8" connection so not using the IEC connector is not a new thing.

robocat

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#822533 20-May-2013 16:45

By my calculation, for 10A cable the copper is about 30 cents versus 15 cents for 2.5A.

Approximations: cable is 1 metre long, cable is three core, copper is NZD10 per kg, individual wire core cross sections are 1mm² versus 0.5mm² as per http://www.epanorama.net/documents/wiring/wire_resistance.htl

richms

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#822643 20-May-2013 20:12

All those savings add up, the thing is in NZ the smaller cables all have to be 0.75mm² anyway, so there isnt the savings you would hope for over the 1mm² needed for a 10 amp cable.

Its about time the IEC did another slimmer plug IMO, my dell power supplies all have a bump on the end to accomodate the cloverleaf socket. if they had a figure 8 they could be thinner, but I guess they want to save a little bit by making it an earthed power supply vs double insulated. Also a 2 pin would let them use a smaller mains plug on the other end.

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Lias

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#822658 20-May-2013 20:43

Toshibas used a figure 8 during the early-mid 2000's

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lxsw20

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#822691 20-May-2013 21:37

Apple still kind of do, just with a funny looking earthed plug buit in.