Tektronix PS2511 & PS2520 - Page 1
Forum section: electronics / projects

author: ChrisMH
author_rank: Contributor
timestamp: November 06, 2012, 05:26:25 am
content: I picked up one of each of these supplies and would like to find a service manual for them, but so far have not had any luck. Does anyone have any suggestions? Both are working at the moment, but I would like to have them on hand if needed.Thanks,Chris

author: casinada
author_rank: Frequent Contributor
timestamp: November 07, 2012, 06:28:24 am
content: Tektronix offers the technical reference that allows you to check and calibrate the power supply. Check for the GWInstek power supplies PPS, PPT, and PPE series. I couldn't find any service manuals or schematics.Good Luck

author: Bryan
author_rank: Frequent Contributor
timestamp: May 17, 2015, 12:02:33 pm
content: Any update on a source of schematics or service manual for the PS2520.Cheers

author: Fireball XL5
author_rank: Newbie
timestamp: June 30, 2015, 05:29:14 pm
content: This site has been mentioned often.http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/The PS2520 Tech Ref and Programming docs are listed - don't know if it's what you were looking for though.Hope it helps.

author: Bushougoma
author_rank: Regular Contributor
timestamp: February 15, 2023, 09:19:55 pm
content: Just wanted to Chime in as I have two of these supplies the PS2511 and PS2520G.First off these supplies use Dallas DS-1220Y battery backed RAMs to store user settings and most importantly their calibration constants. I'd highly recommend replacement of the module (the DS-1220AD is a good substitute) but at a minimum desolder it and read the contents and socket it to make future replacement easier.Tektronix never released schematics for these power supplies they were rebranded GW Insteks. Performance verification and calibration instructions are available from Tektronix for the PS2520 and PS2521G which I've attached. Justclick the bookmark in the PDF for PS2520 Instruction Manual the calibration instructions are on page 55. There are some schematics from Instek floating around online here is the schematic for the PS2520G.Tektronix began to release user manuals and service data digitally on their website beginning in 1995 any devices released before then likely only had print versions.I have been able to find the print version of the user and programmer manuals online for the PS2511 (for ridiculous prices) but haven't been able to find the calibration instructions.The calibration process is similar enough to the documented PS2520 that I was able to figure it out. The steps and calibration indicators on the display for the PS2511 are slightly different from the PS2520.

author: Bushougoma
author_rank: Regular Contributor
timestamp: February 15, 2023, 09:22:30 pm
content: Tektronix PS2511 Calibration Procedure:I'd highly recommend you remove the BBSRAM and backup the existing calibration data with a programmer as I came across an odd (likely rare) firmware glitch during calibration seeOdd Calibration Bug:at the end of this post.Preparation:You will need amultimeter with a 10 amp current rangeand some thick banana leads to connect your meter to the supplies inputs especially when performing the current full scale calibration.Let the instrument warm up for at least 30 minutes with the cover on I waited 1 hour.I'd recommend removing the screws securing the top cover (six on each side and two securing the handle) but leave it on as you will likely need to tweak the voltage reference POT slightly during the voltage full scale calibration.1. Check the back of the instrument you will see aSENSE switchmake sure that it isDOWNindicating that the unit is sensing via theFRONT TERMINALS.Entering Calibration Mode:2. PressSHIFTthenCurrent Down. There will be no indication on the screenTHIS IS NORMAL.3. Enter themodel number of the power supplyon the keypad and press ENTER in this case2511thenpress ENTER.If you seeErr - 099that means you entered the wrong password. Repeat steps 2 - 3 be sure to enter the passwordSLOWLYon the keypad as these instruments can miss the key presses if you type too fast.4. You should seecL00indicating that you have successfully entered calibration mode.Voltage Calibration:5.Press ENTERand you should seecL10indicatingvoltage offset calibration. Set your DMM to measurevolts DCand connect it to the FRONT + and - output terminals of the power supply.Enter the voltage you see on the meter on the keypad and hit ENTER.6. You should now seecL11on the display indicatingvoltage full scale calibration. Look at your meter it should read21.00 voltsif it doesn't. Slide the cover from the power supply back an inch or two and on the right side near the front of the supply you will see a BLUE PotentiometerVR401(the only pot in the instrument). Adjust it until your meter reads21.00 volts. Slide the cover back on press ENTER.7. The unit will displaycL2Fthevoltage calibration of the instrument is complete.Current Calibration:9. Set your meter to measureCURRENT DCand swap theRED LEAD on your meter from the volts DC position to the 10 AMP current position hit ENTER.9. The unit will displaycL20indicatingcurrent offset calibration.Enter the current you see on the meter on the keypad and hit ENTER.10. The unit will displaycL2Fagain indicating the current offset calibration is completehit ENTER.11. The unit will displaycL21indicatingcurrent full scale calibrationenter the current you see on the meter and press ENTER.12. The unit will displaycL2Fagain indicating current full scale calibration is complete.Current calibration of the instrument is now complete.Overvoltage Calibration:13.Disconnect both of your meters leads from the front panel of the supply and press ENTER.The rest of the calibration process is automatic.14. The instrument will displaycL30indicating that it is calibrating the overvoltage protection offset.After about 10 seconds it will then display cL31indicating that it is calibrating the overvoltage protection full scale.After another 10 seconds the instrument will exit calibration modeand return to normal operation the calibration process is complete.Odd Calibration Bug:You likely won't come across this but I figure it's worth mentioning. I encountered a firmware glitch where after the end of calibration the PSU would only output 1 Amp max in constant current mode. Even though the current limit was set higher.The supply was working normally prior to the calibration so I attempted to calibrate it again. Attempting to enter calibration mode to resolve this issue resulted in the unit not outputting ANY offset current during the current offset calibration cL20.This was likely due to an automatic calibration error during the automated overvoltage protection calibration as the unit was outputting it's rated current in calibration full scale mode cL21 prior to the OVP calibration when everything went wonky. I theorize there was improper data in the BBSRAM possibly a bad calibration offset messing up the DAC preventing it from setting the current limit properly.You have two choices to resolve this if you backed up the old BBSRAM data prior to calibration copy the old data back to the BBSRAM (this will restore the unit to proper operation) and run the calibration again.If your old BBSRAM had a dead battery and you don't have data to restore or if you didn't backup the old data wipe the BBSRAM in a programmer by writing all 1s to it. Fill it entirely with HEX FF and run the calibration again.If you chose to blank the new BBSRAM the unit will power up with auto sequencing on. The keypad will not respond to commands with it on to turn it off press theAuto Seq On / Off button. TheAutoindicator will turn off.