Author Topic: Amrel PPS 2322 Calibration - Need 0.1 Ohm .001% 10W Resistor [SOLVED]  (Read 3793 times)

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Offline tzcczt

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I bought a PPS 2322 off eBay but the voltage and current display is off a bit from my Fluke 87v. The calibration is done entirely in software according to the (manual)[http://www.programmablepower.com/products/amrel/PPS/PPS-Manual.pdf] but I need a very particular resistor that I've had no luck in finding:

Precision Shunt Resistor
-
0.1 ohm/10 Amp, 0.001% accuracy (for smaller current) or
0.05% accuracy (for larger current), 20ppm, 10 watts

What do people typically do in these situations?  I'm currently thinking about buying a 10 watt 0.1 ohm resistor with the best accuracy I can find (best I've found is 1% though).
« Last Edit: August 17, 2014, 05:10:09 pm by tzcczt »
 

Offline Rufus

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #1 on: August 15, 2014, 03:25:34 pm »
I bought a PPS 2322 off eBay but the voltage and current display is off a bit from my Fluke 87v. The calibration is done entirely in software according to the (manual)[http://www.programmablepower.com/products/amrel/PPS/PPS-Manual.pdf] but I need a very particular resistor that I've had no luck in finding:

it doesn't need a resistor. The calibration procedure is just using that resistor as a current shunt.

Put your 87v on the 10A current range across the output and convert the current reading to the voltage that would be produced across a 0R1 resistor carrying that current. The calibration will then match and be as good as your 87v.

 

Offline German_EE

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #2 on: August 15, 2014, 05:07:13 pm »
Just out of curiosity I went looking for a 0.1 ohm 0.001% resistor and the best I could find was 0.005% 0.3W which is a custom Vishay part.

77.94 Euro each but if you buy ten the price drops to 65 Euro :scared:
Should you find yourself in a chronically leaking boat, energy devoted to changing vessels is likely to be more productive than energy devoted to patching leaks.

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Online wraper

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #3 on: August 15, 2014, 05:28:08 pm »
Such a current shunt likely will cost more than your 87v and 2322 together. So just use multimeter amps range, you are not a cal lab to do all "properly and traceable". Caveat: measure current fast until your multimeter shunt heats up and reading drifts.
And to make any sense from using such precise current shunt, you need at least 6.5 digit DMM,  not 87v.
« Last Edit: August 15, 2014, 05:38:10 pm by wraper »
 

Offline tzcczt

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #4 on: August 15, 2014, 06:01:03 pm »
Thanks, I didn't think of just measuring the current directly.  Regarding the accuracy, the 87v is the best meter I have.  Right now the power supply is 10'ths of a volt from my meter, I'm just hoping to get it closer than that.
 

Offline tzcczt

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #5 on: August 15, 2014, 06:22:16 pm »
And it looks like the entire endeavor was for naught.  I'm following the manual instructions, but it won't enter calibration mode.  Guessing that's how I picked it up so cheaply  :palm:
 

Online wraper

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #6 on: August 15, 2014, 06:27:04 pm »
In general (don't know about this particular device) there can be some cal disable jumper on the pcb or something like that. It can be password protected (with reset jumper/dip switch somewhere inside).
 

Offline tzcczt

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #7 on: August 17, 2014, 01:38:09 pm »
In general (don't know about this particular device) there can be some cal disable jumper on the pcb or something like that. It can be password protected (with reset jumper/dip switch somewhere inside).

Thanks for the tip, I checked though and couldn't find one.
 

Offline G0HZU

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #8 on: August 17, 2014, 01:53:57 pm »
Quote
What do people typically do in these situations?
I'd imagine that most people who buy one of those PSUs on ebay will just plug it in and use it.

Quote
Topic: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor  (Read 270 times)

Note: your thread title says that you need a 0.1Ohm 0.0001% 10W resistor. Keyboard bounce?  ;D




« Last Edit: August 17, 2014, 02:02:10 pm by G0HZU »
 

Offline kwass

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #9 on: August 17, 2014, 02:37:55 pm »
In general (don't know about this particular device) there can be some cal disable jumper on the pcb or something like that. It can be password protected (with reset jumper/dip switch somewhere inside).

Thanks for the tip, I checked though and couldn't find one.

I have a similar Amrel LPS-305 and can confirm that there is no calibration jumper.  Mine does go into calibration mode by simultaneously pressing "8" and "minus down array"  (which is in the same key position as the "on/off" button on your unit).  Do you have an GP-IB port on a PC to try the remote calibration method?
« Last Edit: August 17, 2014, 02:40:55 pm by kwass »
-katie
 

Offline tzcczt

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Re: Amrel PPS 2322 Calibration - Need 0.1 Ohm .0001% 10W Resistor
« Reply #10 on: August 17, 2014, 05:09:49 pm »
In general (don't know about this particular device) there can be some cal disable jumper on the pcb or something like that. It can be password protected (with reset jumper/dip switch somewhere inside).

Thanks for the tip, I checked though and couldn't find one.

I have a similar Amrel LPS-305 and can confirm that there is no calibration jumper.  Mine does go into calibration mode by simultaneously pressing "8" and "minus down array"  (which is in the same key position as the "on/off" button on your unit).  Do you have an GP-IB port on a PC to try the remote calibration method?


Unfortunately I've got no GPIB card, however I just figured it out the issue.  I found another manual which had different calibration instructions.  For the unit I have, pressing "." "0" "." in sequence puts it in calibration mode. 

Just finished calibration and it matches my Fluke DMM well enough.  Thanks!
« Last Edit: August 17, 2014, 05:12:50 pm by tzcczt »
 

Offline kawal

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Armel PPS-2332 Calibration
« Reply #11 on: May 24, 2017, 01:22:37 am »
Thank you for the tip on the calibration procedure. I was trying the "8/on/off"  and 8 with other combinations and no luck until you post. 

".0." saved the day.'

My unit is from 1991 and last calibration sticker was from 2014.
power transistors are 4 x 2N3055 (2 per channel). 
used my trusty 5.5D HP meter to calibrate.
Current reading seams more precise than voltage reading.


 
 


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