In article o.uk,
"Dave Liquorice" writes:
On Tue, 23 Apr 2013 07:33:05 +0100, MM wrote:

So I reckon, instead of plugging the tyre pump into the in-car
cigarette lighter socket, I should be able to plug it into the
Halfords unit instead.

Anyone see a problem with this plan?

I guess you want to use the compressor for something else away from the
car not the implied car tyre inflation?

If the 85 W quoted is correct thats at least 7A @ 12v. The current draw

These also take one hell of a switch-on surge. SMPSUs tend to need
to be specially designed to be able to deliver large switch-on surges.

will depend on how hard the compressor is working, which will be related
to output pressure. The higher the output pressure the more work the
compressor has to do so it will draw more current.

I use one of the portable jumpstarter packs with a built-in sealed
lead acid battery and compressor. The trouble is finding a good one;
many of them are complete crap, and have fake batteries which are a
tiny fraction of the capacity which their size and markings claim,
and some of the compressors and tyre valve couplers are crap too.

--
Andrew Gabriel
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