Keithley 6487/E Digital-Multimeter, DMM, 6487/E Scheda Tecnica

The Model 6485/6487 can be used within one minute after it is turned on. However, the 
instrument should be turned on and allowed to warm up for at least one hour before use to 
achieve rated accuracy. If the instrument has been exposed to extreme temperatures, allow 
extra time for the internal temperature to stabilize.

Voltage offset correction should be performed periodically to null input amplifier offsets. 
Install the shielding cap on the INPUT jack, then use the CAL:VOFFSET selection in the 
main MENU. To perform correction via remote, send CAL:UNPR:VOFF.

To help maintain stability and accuracy over time and changes in temperature, the Model 
6485/6487 periodically measures internal voltages corresponding to offsets (zero) and 
amplifier gains; a process known as autozeroing. With autozero disabled, measurement 
speed increases up to three times, but measurement accuracy will be reduced. It is recom-
mended that autozero only be disabled for short periods of time. 

To toggle autozero on or off, press the AZERO button. When autozero is enabled, a colon 
will be displayed after the reading. Via remote, send SYST:AZER ON or SYST:AZER 
OFF.

When zero check is enabled (on), the input amplifier is reconfigured to shunt the input signal 
to low. From the front panel, enable/disable zero check by pressing the ZCHK key. Refer to 

 for bus commands. Leave zero check enabled when connecting or disconnecting 

input signals.