tim's journal

Keithley 6430 notes...

It says, on page 2-4,

Whenever the Remote PreAmp is connected to the mainframe, adhere to the following rules to achieve best performance:

• Do not use INPUT/OUTPUT HI and 4-WIRE SENSE HI on the mainframe. Access these terminals at the Remote PreAmp. Hmm, that seems straight-forward. but just HI?
• Access input/output low at the Remote PreAmp or at the mainframe, but not both. What about the SENSE LO? Test circuit common should be tied to one point to avoid ground loops which could generate error currents. Fair enough...
• Do not use guard from the mainframe and the Remote PreAmp at the same time. Use one or the other.