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General => General Discussion => Topic started by: USMCPMEL on 03-16-2009 -- 12:59:43

Title: Agilent 34970A 4 wire ohms will not take new constants
Post by: USMCPMEL on 03-16-2009 -- 12:59:43
I believe the readings are out of range and it will not take the new cal constants on 4 wire ohms. I have got everything else to work so far and it comes down to this. 1 k ohms is reading 1.00186 and the other ranges are sililar to this one. Any ideas?
Title: Re: Agilent 34970A 4 wire ohms will not take new constants
Post by: flew-da-coup on 03-16-2009 -- 14:29:42
What are you using for a standard? Just curious.
Title: Re: Agilent 34970A 4 wire ohms will not take new constants
Post by: USMCPMEL on 03-16-2009 -- 15:10:09
5520A with a fresh calibration. (smelling ) umm it has that just cal'd smell!!!
Title: Re: Agilent 34970A 4 wire ohms will not take new constants
Post by: Xrayvissle on 03-17-2009 -- 16:13:16
Well, we stand in the same boat, I'm doing a cal on one of those right now myself.  The 5520 may not be accurate enough for the 4 wire ohms measurement, and definatly not for the rest of the readings.  If you have a 5700 or equivilent thats your best bet.  I'd recommend verifying the ohms out from the '20 with an accurate multimeter with 7 1/2 dig's of res.  Thats the best I got for ya man. 
Title: Re: Agilent 34970A 4 wire ohms will not take new constants
Post by: USMCPMEL on 03-19-2009 -- 16:12:31
What readings is it not accurate enough for??
Title: Re: Agilent 34970A 4 wire ohms will not take new constants
Post by: WestCoastCal on 03-19-2009 -- 17:11:45
Attached is a datasheet for a 34970A with TAR's calculated with the 5520A 1 year specs.  Because of all the less than 4:1's we use a 5720A and 5790A.  Hope this helps.  Let me know if you need calculated TUR's.  Additionally; I'm not a big fan of the 'synthesized' resistance (or whatever you call it in the 55X0A series), you may want to try a true resistance.