Keithley 4200-SCS Reference Manual page 5

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 Instruments 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.
Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedance-limited sources. NEVER
connect switching cards directly to AC mains. When connecting sources to switching cards, install protective devices to limit fault current
and voltage to the card.
Before operating an instrument, ensure that the line cord is connected to a properly-grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks before each use.
When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main input power
disconnect device must be provided in close proximity to the equipment and within easy reach of the operator.