Keithley 486 Quick Reference Manual page 7

For maximum safety, do not touch the Model 487 con-
nections, test fixture, test cables or connections to any
other instruments while power is applied to the circuit un-
der test. Turn off all power and discharge all capacitors
before connecting or disconnecting cables or jumpers.
Also, keep the test fixture lid closed while power is ap-
plied to the device under test. Safe operation requires the
use of the lid interlock.
Do not touch any object which could provide a current
path to the common side of the circuit under test or power
line (earth) ground.
Do not exceed the maximum signal levels of the instru-
ment, as shown on the rear panel and as defined in the
specifications and operation section of the instruction
manual.
Connect the chassis of the test fixture to safety earth
ground using #I 8 AWG or larger wire.
Instrumentation and accessories should not be con-
nected to humans.
Maintenance should only be performed by qualified serv-
ice personnel. Before performing any maintenance, dis-
connect the line cord and all test cables from the instru-
ment.
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