Keithley 2500 Service Manual Download

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Do not touch any object that could provide a current path to the common side of the circuit under test or power
line (earth) ground. Always make measurements with dry hands while standing on a dry, insulated surface ca-
pable of withstanding the voltage being measured.

The instrument and accessories must be used in accordance with its specifications and operating instructions
or the safety of the equipment may be impaired.

Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications
and operating information, and as shown on the instrument or test fixture panels, or switching card.

When fuses are used in a product, replace with same type and rating for continued protection against fire hazard.

Chassis connections must only be used as shield connections for measuring circuits, NOT as safety earth
ground connections.

If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation
requires the use of a lid interlock.

If a

screw is present, connect it to safety earth ground using the wire recommended in the user documen-

tation.

The

symbol on an instrument indicates that the user should refer to the operating instructions located in

the manual.

The

symbol on an instrument shows that it can source or measure 1000 volts or more, including the com-

bined effect of normal and common mode voltages. Use standard safety precautions to avoid personal contact
with these voltages.

The

WARNING

heading in a manual explains dangers that might result in personal injury or death. Always

read the associated information very carefully before performing the indicated procedure.

The

CAUTION

heading in a manual explains hazards that could damage the instrument. Such damage may

invalidate the warranty.

Instrumentation and accessories shall not be connected to humans.

Before performing any maintenance, disconnect the line cord and all test cables.

To maintain protection from electric shock and fire, replacement components in mains circuits, including the
power transformer, test leads, and input jacks, must be purchased from Keithley Instruments. Standard fuses,
with applicable national safety approvals, may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as long as they are equivalent to the original
component. (Note that selected parts should be purchased only through Keithley Instruments to maintain ac-
curacy and functionality of the product.) If you are unsure about the applicability of a replacement component,
call a Keithley Instruments office for information.

To clean an instrument, use a damp cloth or mild, water based cleaner. Clean the exterior of the instrument
only. Do not apply cleaner directly to the instrument or allow liquids to enter or spill on the instrument. Prod-
ucts that consist of a circuit board with no case or chassis (e.g., data acquisition board for installation into a
computer) should never require cleaning if handled according to instructions. If the board becomes contami-
nated and operation is affected, the board should be returned to the factory for proper cleaning/servicing.

Rev. 10/99