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Sofie
 
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Default Turn Your Power Supply into an Ohmmeter - It's Free!

Watt Sun:
Just a little cumbersome.... isn't it??
As you indicated, there is a risk of smoking low ohm, low wattage resistors
unless you already know the value... if that is the case then why are you
measuring it??......
.....and the accuracy is compromised because you are measuring the voltage
and then measuring the current..... and you are at the mercy of the
regulation of your power supply.
2 meter operations instead of one... the inherent innaccuracy of one of the
readings is further compromised by the inaccuracy of the 2nd reading.....
give me a DMM or VOM with a dedicated OHMS function any time..
Actually, the much more used and handier version of this is the "flip-side"
where you measure the voltage across a known-value resistor in the circuit
to determine the approximate current.... most techs do this all the time
while routinely troubleshooting.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
---------------------------------


"Watson A.Name - 'Watt Sun'" wrote in message
I got tired of switching the leads of my DMM. Suddenly if dawned on
me that I can just set the power supply to 10.0V for exaample, and
read the current, and then divide the voltage by the current to find
the resistance. Like I put a resistance on the PS, it reads 10.0V and
the current is .018A, so 10 / .018 gives 555.6 ohms. Must be a 560
ohm resistor.

I turned my PS into an ohmmeter - FREE!

Hee-hee - Work smarter, not harder!

Of course, make sure the current stays low so the resistance doesn't
overheat. For low resistances use a volt or less.