Brief Teardown: OMEGA CL8300 (AOIP SN 8310) DC voltage / current standard

[nidlaX]

I received a holiday goody this week: an OMEGA CL8300 (CL8302 variant) DC V/mA standard. The CL8300 series, most recently marketed by OMEGA as high precision calibrators, are actually rebadged from the SN 8310 series of DC voltage/current source products made by the French company AOIP. Today, AOIP designs and sells a variety of high precision calibration equipment, although it appears that they used to sell more generalized test equipment such as rebadged Keithley multimeters as well.

References:
OMEGA CL8300 product page: http://www.omega.com/pptst/CL8300.html
AOIP SN 8310 product page: http://www.aoip.com/product/sn-8310-2/

The CL8300 is specified as follows:
Range   Limit         Resolution  90 days acc.  1 year acc.
100 V   +110.0000 V   100 µV      0.0020% + 2   0.004% + 3
10 V    +11.00000 V   10 µV       0.0020% + 2   0.004% + 3
1 V     +1.100000 V   1 µV        0.0025% + 4   0.005% + 6
100 mV  +110.0000 mV  100 nV      0.0035% + 20  0.007% + 20
100 mA  +110.0000 mA  100 nA      0.0030% + 4*  0.006% + 8*
10 mA   +11.00000 mA  10 nA       0.0030% + 4*  0.006% + 8*
1 mA    +1.100000 mA  1 nA        0.0030% + 4*  0.006% + 8*
*Note: The accuracy specs for the current ranges taken from the latest datasheet on OMEGA's website are notably less conservative than those given in the latest AOIP SN 8310 manual.

Four variants were available:
-CL8301 / SN 8310-1: Basic model (115/230 V power supply and RS 232).
-CL8302 / SN 8310-2: Basic model with battery and charger.
-CL8303 / SN 8310-3: Basic model with IEEE-488 interface.
-CL8304 / SN 8310-4: Basic model with battery, charger and IEEE-488
interface.

Now let's go inside. This will only be a partial teardown as I haven't read the full teardown procedure, and I don't want to risk damaging the board to board interconnects. Pictures can be clicked for full resolution.

The unit is nice and compact, designed for benchtop and portable use.






Top and bottom covers pop off easily after removing some screws.


Top side: digital board and battery.


Clearly a multi-use board with a lot of un-populated components. Several other AOIP products feature a similar form factor / layout.


This battery is toast, it measures 0 V! A non-RoHS compliant paperweight now... AOIP / OMEGA would charge you around $400 for the battery plus the little charger board on the left. I uninstalled the entire battery option, and the battery itself will be going to ewaste.


Guess what's under this!


Bottom side: analog board.


Here's potentially the money shot of the voltage reference. I won't attempt to remove the heatsink, but people speculate it's an AD588 or AD688.


Some German caps.


Some nice relays indeed.


Here I proceeded to do some sanity checks using my Keithley 2000. Keep in mind that my 2000 is almost certainly out of cal after the resistor network replacement.
















Overall, a nice little unit. There are a few small niggles here and there, but for $50 I can't complain (much). Thanks for looking, hope you found it interesting!

[radhaz]

Very nice, I didn't know Omega sold a benchtop calibrator.

[Vgkid]

Thanks for the teardown.
 The only reason I could see them marketing it is to calibrate their thermocouples/ meters.

[nidlaX]

Thanks for the teardown.
 The only reason I could see them marketing it is to calibrate their thermocouples/ meters.

Indeed, I think that is exactly what my unit was used for in its past life. O0

[KSP]

Sorry to revive an old post, but I don't suppose OP has the programming manual for this unit? I have the AOIP version and the only manual I could find is the French one... And I don't speak French 

[nidlaX]

Sorry to revive an old post, but I don't suppose OP has the programming manual for this unit? I have the AOIP version and the only manual I could find is the French one... And I don't speak French 

Hey! A generous person from Omega was able to provide me with some scanned documentation and a default calibration password. I was able to download a full English manual and Labview driver directly from AOIP here: http://www.aoip.com/product/process-voltage-current/sn-8310-2/. If you need the calibration password, send me a DM.

By the way, if anyone comes across or has access to firmware for this unit, please let us know.

[KSP]

Hey! A generous person from Omega was able to provide me with some scanned documentation and a default calibration password. I was able to download a full English manual and Labview driver directly from AOIP here: http://www.aoip.com/product/process-voltage-current/sn-8310-2/. If you need the calibration password, send me a DM.

By the way, if anyone comes across or has access to firmware for this unit, please let us know.

Thank you very much for this! And also sorry about the late reply. I did look on the AOIP website before, but I must have had what my old lady would call "a man's look", because I completely overlooked the download links 

And the calibration password would be very useful, I shall DM you