Better resistor for WT3 calibration

[czag]

Any suggestions for a better resistor to calibrate the WT3. I would like to use a 0.1% tolerance resistor, I just need to know what ohm value and the source for any recommendations I receive here.

Thanks,
Chris

[Mark Bunte]

Re: Better resistor for WT3 calibration

Here's one:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=MR106-1K-.01-ND

[rogoll]

Re: Better resistor for WT3 calibration

I just went to the local electronics parts place (I live near Birmingham, AL...metro area) and got a 0.1% 1K Ohm resistor. It just improves the degree of precision (supposedly...it's probably more of an OCD thing, though).

[John L. Murphy]

Re: Better resistor for WT3 calibration

The resistor Mark linked is a 0.01% part costing $5.95 each. Yikes that's expensive!

Here are some less expensive 0.1% parts to consider for use with WT3.

1k Ohms, 1/2 Watt, $.16 in singles:
http://search.digikey.com/scripts/Dk...CMF1.0KHBCT-ND

100 Ohms, 1/2 Watt, $.16 in singles:
http://search.digikey.com/scripts/Dk...=CMF100HBCT-ND

20 Ohms, 1/2 Watt, $.29 in singles:
http://search.digikey.com/scripts/Dk...e=CMF20QBCT-ND

If you are ordering a 0.1% 1k calibration resistor you might want to also get a few 100 and 20 Ohm pieces for calibration and/or for checking calibration in the lower range. These high accuracy resistors generally reveal the WT3 to be accurate to about 0.1% when calibrated with a 0.1% resistor.

Regards,

John