Build Instructions

Collapse

• 1

  Assemble the XJW01 kit

  The XJW01 kit comes with a bunch of resistors and capacitors that need to be soldered in. Also note that the kit comes with a small ziplock bag with 'calibration resistors'. You won't have to use these in the build, that will come later when calibrating.
  

  Use ribbon cable to connect the display and keypad to the main circuit board. I've used around 15 cm of ribbon cable for the display and around 10 for the keypad.

  After you're done, you can test the kit with a 12V bench power supply to make sure it turns on. Don't worry too much about the values it shows, it might not be calibrated properly.

• 2

  Print the case parts

  Print the attached case parts. I've used 0.2mm layer height with a 0.4mm nozzle with 35% infill, printing PLA. The pieces can all be printed flat on the bed, but you might need to rotate them in your slicer.
  

• 3

  Calibrate the meter

  It's time for calibration. It's not a super-obvious procedure, but it is fairly easy.

  First, measure the included resistors as accurately as possible. There should be a 40R, 1K, 3K, 9K, 10K and 100K resistors. Go nuts with 50 power line cycles, averaging, 6,5 digits, 4-wire measurements and all that. We will use the measurements you've done to calibrate the meter to.
  

  Once you've measured the resistors to an accurately enough degree, it's time to start the calibration procedure:

  1. Turn the unit on
  2. Perform a short test lead calibration. Clamp the Kelvin clips together and press the "Zero" button
  3. Perform an open test lead calibration. Disconnect the kelvin clips and press the "Zero" button
  4. Hold down MENU for approximately 3 seconds, this will bring up the options menu
  5. Press RNG to enter calibration mode, the display should now show "Z0"
  6. For the calibration, we will adjust the instrument to exactly match the previously measured resistor values (as well as some other parameters). Use the CLR (up) and SP/ESR buttons (down) to adjust the values. Use FREQ to go to the next parameter and QTY to go back.
  7. Set the values of the different parameters as follows:

  Step	Target Value	Notes
  Z0	Z=0	Short the Kelvin clips
  Z1	Z=0	Short the Kelvin clips
  Z2	Z=0	Short the Kelvin clips
  R1	40R resistor	Connect the resistor and try to match what you previously measured with your multimeter
  R1X	θ=0	Leave the resistor connected
  R2	1K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  R2X	θ=0	Leave the resistor connected
  R3	10K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  R3X	0 pF	Leave the resistor connected
  R4	100K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  R4b	100K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  R4X	0 pF	Leave the resistor connected
  G1	3K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  G1X	0 pf	Leave the resistor connected
  G2	9K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  G2b	9K resistor	Connect the resistor and try to match what you previously measured with your multimeter
  G2X	0 pf	Leave the resistor connected
  PhX	θ=0	Connect the 1K resistor

  After calibration, make sure to save your changes with the Hand/Auto button!
  

View all 9 instructions