I recently replaced two Keithley 2450 by one Keithley 2614B. I’m mostly using them to source voltages on semiconductor gates, but the versatility of the Keithley 2614B enables me to broaden the range of applications.

Sourcing gate voltages usually mean going above the limit set by the instrument in its default configuration. The keithley 2614B is able to source voltages up to 200V, but by default, there is an imposed limit of 20V. Trying to source higher voltages would likely result in a -350error:

error you get on a keithley 2600 when trying to source voltages >20V without tuning the interlock.

After looking for hours on the web, my friend Saurav told me there was a trick that consisted in bypassing the safety interlock.

On the Keithley 2600 models, the trick is to use a 25way D-sub male connector and short pins 15 and 17, as follows:

25 way D-sub male conector with pins 15 and 17, connected on the Keithley 2600 interlock.

On the Keithley 2400-type models, the trick is to bypass the connections 2 and 3 with a 3-pin connector.

interlock bypassed on the Keithley 2400.

Now I can use the sourcemeter’s full range. I would advice to always think about setting up software limits