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PA-396 Rev. B / February 2016
3
Safety precautions
The following safety precautions should be observed before using this product and any associated instrumentation. Although
some instruments and accessories would normally be used with nonhazardous voltages, there are situations where hazardous
conditions may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety precautions
required to avoid possible injury. Read and follow all installation, operation, and maintenance information carefully before using
the product. Refer to the user documentation for complete product specifications.
If the product is used in a manner not specified, the protection provided by the product warranty may be impaired.
The types of product users are:
Responsible body
is the individual or group responsible for the use and maintenance of equipment, for ensuring that the
equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately trained.
Operators
use the product for its intended function. They must be trained in electrical safety procedures and proper use of the
instrument. They must be protected from electric shock and contact with hazardous live circuits.
Maintenance personnel
perform routine procedures on the product to keep it operating properly, for example, setting the line
voltage or replacing consumable materials. Maintenance procedures are described in the user documentation. The procedures
explicitly state if the operator may perform them. Otherwise, they should be performed only by service personnel.
Service personnel
are trained to work on live circuits, perform safe installations, and repair products. Only properly trained
service personnel may perform installation and service procedures.
Keithley Instruments products are designed for use with electrical signals that are measurement, control, and data I/O
connections, with low transient overvoltages, and must not be directly connected to mains voltage or to voltage sources with high
transient overvoltages. Measurement Category II (as referenced in IEC 60664) connections require protection for high transient
overvoltages often associated with local AC mains connections. Certain Keithley measuring instruments may be connected to
mains. These instruments will be marked as category II or higher.
Unless explicitly allowed in the specifications, operating manual, and instrument labels, do not connect any instrument to mains.
Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable connector jacks or test
fixtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage levels greater than
30 V RMS, 42.4 V peak, or 60 VDC are present. A good safety practice is to expect that hazardous voltage is present in any
unknown circuit before measuring.
Operators of this product must be protected from electric shock at all times. The responsible body must ensure that operators
are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential
human contact. Product operators in these circumstances must be trained to protect themselves from the risk of electric shock. If
the circuit is capable of operating at or above 1000 V, no conductive part of the circuit may be exposed.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under
test. ALWAYS remove power from the entire test system and discharge any capacitors before: connecting or disconnecting
cables or jumpers, installing or removing switching cards, or making internal changes, such as installing or removing jumpers.
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 capable of withstanding the
voltage being measured.
For safety, instruments and accessories must be used in accordance with the operating instructions. If the instruments or
accessories are used in a manner not specified in the operating instructions, the protection provided by 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.
Chassis connections must only be used as shield connections for measuring circuits, NOT as protective earth (safety ground)
connections.
The
WARNING
heading in the user documentation explains dangers that might result in personal injury or death. Always read
the associated information very carefully before performing the indicated procedure.