TCLUG Archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [TCLUG:22753] Measuring power consumption (was MP3 player)



why not just use an inductive curent meter?

Thank You,
        Ben Kochie (ben@nerp.net)

*-----------------------*  [ - * - * - * - * - * - * - * - ]
| Unix/Linux Consulting |  [ Haiku Error Message:          ]
|  PC/Mac Repair        |  [  Chaos reigns within.         ]
|   Networking          |  [  Reflect, repent, and reboot. ]
| http://nerp.net       |  [  Order shall return.          ]
*-----------------------*  [ - * - * - * - * - * - * - * - ]

 "Unix is user friendly, Its just picky about its friends."

On Tue, 17 Oct 2000, Bill Layer wrote:

> The multimeter will do just fine but you will have to play one trick or 
> another to make the necessary series connection with the power cord to 
> measure current draw.. I have a special, short extension cord that has one 
> conductor broken so that the meter may be inserted in series with the loop.
> 
> Set the meter for the current scale and measure the current draw with the 
> device powered on. Then, keeping the device powered on, set the meter for 
> an AC RMS voltage scale and measure the supply voltage at the wall - it's 
> not wise to estimate, as AC mains voltages can be anywhere between 109 and 
> 126VAC - with 117 being nominal. Once you know current and RMS supply 
> voltage, power (wattage) calculation is this easy:
> 
> P = E * I (Where P is power (in watts), E is energy (in volts) and I is 
> current (in amperes))
> 
> I should mention that most all (even inexpensive) meters automatically give 
> AC voltage readings in RMS - so don't get too concerned about this issue. 
> If the meter doesn't say otherwise, it's giving the reading in RMS.
> 
> 
> 
> 
> 
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: tclug-list-unsubscribe@mn-linux.org
> For additional commands, e-mail: tclug-list-help@mn-linux.org
>