User manual

Model 6485 and 6487 User’s Manual Measurements and Sourcing Voltage 3-5
Current measurements
Precautions
Model 6485 precautions
t^okfkd The maximum safe voltage between picoammeter LO and chassis ground
(common mode voltage) is 42V. The Model 6485 does not internally limit
the LO to chassis voltage. Exceeding 42V can create a shock hazard.
If it is possible for the DUT or external supply to present more than 42V to
the input HI, it is imperative that the connection between input LO and the
external voltage source be sufficiently low impedance and capable of car-
rying the short-circuit current of the source, in order that the LO not exceed
42V.
`^rqflk The LO to chassis breakdown voltage is 500V. Exceeding this voltage may
cause damage to the instrument.
The maximum input voltage and current to Model 6485 is 220V peak and
21mA. Exceeding either of these values may cause damage to the instru-
ment that is not covered by the warranty.
Model 6487 precautions
t^okfkd The maximum safe voltage between picoammeter LO and chassis ground
(common mode voltage) is 505V. The Model 6487 does not internally
limit the LO to chassis voltage. Exceeding 505V can create a shock hazard.
If it is possible for the DUT or external supply to present more than 505V
to the input HI, it is imperative that the connection between input LO and
the external voltage source be sufficiently low impedance and capable of
carrying the short-circuit current of the source, in order that the LO not
exceed 505V.
`^rqflk The maximum input voltage and current to Model 6487 is 505V peak and
21mA. Exceeding either of these values may cause damage to the instru-
ment that is not covered by the warranty.