| 1 | Select the lowest range of the voltmeter. | |
| 2 | Close the channel and measure the voltage with a sensitive voltmeter. | |
| 3 | The three-pole switch was originally used to switch a voltmeter guard along with the signal lines. | |
| 4 | Then connect the voltmeter to the HI and LO output terminals of the switch card. | |
| 5 | Fig 3. Typical system to make I-V curves on solar cells, consisting of a current source and voltmeter. |