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Old 25th September 2021, 22:17   #1
MSS
This is my second home
 
Rover 75CDT, Jaguar XF-S 3.0V6, V'xhall Omega V6 Estate, Twintop 1.8VVT, Astra Estate and Corsa 1.2

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Default CDT quiescent drain measurement with clamp meter

In another thread a member mentioned the use of a clamp meter for measuring the quiescent current with a clamp meter.

Well, here it is being done earlier today just as a check.

Note the use of a brick to simulate closed bonnet.

https://the75andztclub.co.uk/forum/a...1&d=1632607692

Measurement at time 0 - a few seconds after car being locked with everything switched off

https://the75andztclub.co.uk/forum/a...1&d=1632607830


Measurement at 2 minutes (the drain reaches this value in a number of steps as systems shut down)

https://the75andztclub.co.uk/forum/a...1&d=1632607830


Measurement at 12 minutes

https://the75andztclub.co.uk/forum/a...1&d=1632608005


Measurement at 20 minutes

https://the75andztclub.co.uk/forum/a...1&d=1632608031


The final value is about 25mA.


I would accept up to 50mA but would definitely investigate if the final value was over 75mA


A clamp meter certainly makes taking these measurements rather straightforward. However, the cheap clamp meters are of no use as they only measure AC current. An AC/DC current clamp meter is required and the one being used here is the cheapest decent one of which I am aware. It is available for just over £40 to £50 from various suppliers. It is a UNI-T UT210E.


Some cars have more complex, multi-lead, connections to battery posts e.g. our Vauxhall Twintop. In that case I just use a jump lead to bring out a single lead for the clamp.
Attached Images
File Type: jpg Clamp-1.jpg (115.2 KB, 87 views)
File Type: jpg Clamp-2.jpg (93.7 KB, 85 views)
File Type: jpg Clamp-3.jpg (87.9 KB, 44 views)
File Type: jpg Clamp-4.jpg (75.9 KB, 76 views)
File Type: jpg Clamp-5.jpg (92.4 KB, 81 views)

Last edited by MSS; 26th September 2021 at 08:46..
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