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Products => Test Equipment => Topic started by: Magnum on April 19, 2015, 06:13:29 pm

Title: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 06:13:29 pm
Hello,

for my home lab I am looking for a cheap DC voltage calibrator. I don't want to spend hundreds of Euros and was thinking about something like a Power Designs 2005A power supply which IMHO can be used as a poor mans calibrator. Are there any other recommendations?

Magnus
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: dom0 on April 19, 2015, 06:16:00 pm
Good and proper DMM and a supply with a ten turn pot for voltage. Much cheaper and versatile. For "pure DC calibrator" applications it's of course not as convient as a real calibrator where you just dial the voltage in and are done.

Newer programmable supplies might be an option, too, but are usually not as precise or stable.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 06:22:43 pm
I have a Keithley 2000 and 2015 to measure and use a Rigol DP832 as source. But IMHO the DP832 is not stable enough.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Vgkid on April 19, 2015, 07:08:34 pm
What about getting one of the malone references, or one of the calibrated ebay refs.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: gdewitte on April 19, 2015, 07:29:13 pm
+1 for the Malone references: http://www.voltagestandard.com/ (http://www.voltagestandard.com/)
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: JBaughb on April 19, 2015, 07:56:36 pm
You can pick up a .002% 10V source form voltagestandard.com and some high stability resistors to create some highly accurate calibration standards.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 08:33:34 pm
Thanks for all the replies. I want to calibrate a 6.5 data logger (Agilent 34970A). I know that won't work to specs with a 6.5DMM, but I want to be as close as possible.
I didn't know voltage standard has a unit with 5 selectable DC reference voltages. I think that will do the job.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 08:36:02 pm
Update: Voltage Standard is on vacation until Mid May, so I have to keep searching..
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: dom0 on April 19, 2015, 08:57:37 pm
Are you sure the 34970 needs a cal? Because, if it's not way off, it's hard to tell with just another 6.5 DMM.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: McBryce on April 19, 2015, 08:58:16 pm
How about one of these? Is that accurate enough for what you need?

http://www.ebay.de/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Modul-new-/161510338042?pt=LH_DefaultDomain_77&hash=item259ac42dfa (http://www.ebay.de/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Modul-new-/161510338042?pt=LH_DefaultDomain_77&hash=item259ac42dfa)

McBryce.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 09:19:48 pm
Are you sure the 34970 needs a cal? Because, if it's not way off, it's hard to tell with just another 6.5 DMM.
The FRAM for the Cal-Data is gone and I have to put in a new chip. After that it will need a new calibration.
Title: Re: Looking for cheap (used) DC calibrator, recommendations?
Post by: Magnum on April 19, 2015, 09:23:35 pm
How about one of these? Is that accurate enough for what you need?

http://www.ebay.de/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Modul-new-/161510338042?pt=LH_DefaultDomain_77&hash=item259ac42dfa (http://www.ebay.de/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Modul-new-/161510338042?pt=LH_DefaultDomain_77&hash=item259ac42dfa)

McBryce.

It is accurate enough as I can check it against the two Keithleys. For the calibration 100mV, 1V and 10V would be optimum. I'll check Ebay and see what I can get. Thanks for the replies.