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 personnel who recognize shock hazards and are familiar 
with the safety precautions required to avoid possible injury. Read and follow all ins
tallation, 
operation, and maintenance information carefully before using the product. Refer to the user 
documentation for complete product specifi cations. 
If the product is used in a manner not specifi ed, 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 specifi cations 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 vol
tage 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 products ar
e 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 specifi cations, 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 fi xtures. 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 s
afety 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 shoc
k. 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 co
rd 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. 
For maximum safety, do not touch the product, tes
t cables, or a
ny 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.