dethlore
0
- Joined
- Apr 4, 2011
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This isn't the first driver I've built, so I'm feeling kinda stupid that I have to ask this...
I'm building this driver to work on 1.6A to give an M140 a long life. The problem is thus:
When DMM is hooked up in series to measure current, it reads 1.43A.
When I measure volts across the 1Ohm/5Watt resistor on the dummy load I get 1.77V.
The measurement of the resistor in ohms is 2.1 with the probe in ohms at 1.1, so I think it's safe to say the resistor really is 1Ohm and measured current across the resistor is 1.77A.
What can cause this difference and which one is accurate?
I'd rather not go below my spec goal, but I would HATE to kill the diode.
Thanks for your help in advance!
I'm building this driver to work on 1.6A to give an M140 a long life. The problem is thus:
When DMM is hooked up in series to measure current, it reads 1.43A.
When I measure volts across the 1Ohm/5Watt resistor on the dummy load I get 1.77V.
The measurement of the resistor in ohms is 2.1 with the probe in ohms at 1.1, so I think it's safe to say the resistor really is 1Ohm and measured current across the resistor is 1.77A.
What can cause this difference and which one is accurate?
I'd rather not go below my spec goal, but I would HATE to kill the diode.
Thanks for your help in advance!