Here goes the stupid question. Just want to be sure before I contact the seller. I bought 120 5% .47R 3W resistors from Mouser and the markings on them are correct from what I can tell (Yellow,Violet,Silver,Gold). The problem is they Ohm out at 3R when I tested them. Is this correct? Am I missing something here because all of the 1/4W resistors I ordered match the stated values.
Be gentle
James
Be gentle
James
James,
I am mostly color blind so I never gave in to trying to figure out the color coding. I would inevitably get it wrong anyway.
Test another resistor with your DMM. One you are sure of the value. Then test your .47R resistors and see what happens. If the first reads correct and you still get 3R on the new ones then I guess you have 3R Guess you could put 6 of them in parallel and you would have your .5R for each side of a Pass power supply
Uriah
I am mostly color blind so I never gave in to trying to figure out the color coding. I would inevitably get it wrong anyway.
Test another resistor with your DMM. One you are sure of the value. Then test your .47R resistors and see what happens. If the first reads correct and you still get 3R on the new ones then I guess you have 3R
Guess you could put 6 of them in parallel and you would have your .5R for each side of a Pass power supply Uriah
join them all together in series and measure the resistance of the series combination. Expect 55r to 60r.
Divide by 120 to get an approximate average value for resistance.
You could compare a 56r 1% resistor to allow you to correct for your DMM inaccuracy.
Have you checked what your meter reads when you short your test leads together?
I have found that using a 0.1% tolerance resistor to accurately monitor a CCS and use that CCS to drive a current through low value resistors to be a far better method to check individual resistances (voltage drop / current = resistance). I can match low value resistors 0r1 to 1r0 to better than 0.2% with a little bit of care.
Divide by 120 to get an approximate average value for resistance.
You could compare a 56r 1% resistor to allow you to correct for your DMM inaccuracy.
Have you checked what your meter reads when you short your test leads together?
I have found that using a 0.1% tolerance resistor to accurately monitor a CCS and use that CCS to drive a current through low value resistors to be a far better method to check individual resistances (voltage drop / current = resistance). I can match low value resistors 0r1 to 1r0 to better than 0.2% with a little bit of care.
Yep that is what they are for. I am building 5 Aleph-J X's. I have to call Mouser for an RMA and order a different brand I gather since all 120 look wrong 8(.
James
buy new test leads.
If that does not reduce the zero ohm reading to below 0r2, then buy a new meter.
Doesn't the meter have some kind of adjustment to adjust the R-reading to zero with shorted leads?
jd
it is meters very common failure (Unless the leads are really f**cked )
often meters when voltage is applied by accident to ohm section ( and the protection of the device is not enough ) then the meter looses the ability to measure correct very low resistance .....generally from 100R and above it could work very fine
often meters when voltage is applied by accident to ohm section ( and the protection of the device is not enough ) then the meter looses the ability to measure correct very low resistance .....generally from 100R and above it could work very fine
Well, It is a new meter to me so I found the manual and figured out how to zero the resistance. Guess what? damn things checked out okay now lol.
I will look into getting new leads as they are crappy ones I just had lying around for my automotive multimeter. When I bought this meter second hand (Triplett 4800) it did not come with any.
Turns out I am on some good glue Thanks! for all the help guys.
James
I will look into getting new leads as they are crappy ones I just had lying around for my automotive multimeter. When I bought this meter second hand (Triplett 4800) it did not come with any.
Turns out I am on some good glue
Thanks! for all the help guys.James
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