Keithley 2461 Reference Manual

Section
2: General operation Model 2461 Interactive SourceMeter® Instrument
Reference Manual
2-84 2461-901-01 A/November 2015
Test connections
To prevent electric shock, test connections must be configured such that the user cannot
come in contact with conductors or any device under test (DUT) that is in contact with the
conductors. It is good practice to disconnect DUTs from the instrument before powering the
instrument. Safe installation requires proper shields, barriers, and grounding to prevent
contact with conductors.
There is no internal connection between protective earth (safety ground) and the LO
terminals of the Model 2461. Therefore, hazardous voltages (more than 30 V
rms
) can appear
on LO terminals. This can occur when the instrument is operating in any mode. To prevent
hazardous voltage from appearing on the LO terminals, connect the LO terminal to
protective earth if your application allows it. You can connect the LO terminal to the chassis
ground terminal on the front panel or the chassis ground screw terminal on the rear panel.
Note that the front-panel terminals are isolated from the rear-panel terminals. Therefore, if
you are using the front-panel terminals, ground to the front-panel LO terminal. If using the
rear-panel terminals, ground to the rear panel LO terminal.
Be aware that hazardous voltages can appear on the LO terminals even if the terminals are
not presently selected. The TERMINALS FRONT/REAR switch selects the active terminals
for the measurement. It does not disconnect the terminals.
The maximum input voltage between FORCE/SENSE HI and FORCE/SENSE LO 105 V
peak
.
Exceeding this value may create a shock hazard.
The maximum common-mode voltage (the voltage between FORCE/SENSE LO and chassis
ground) is 250 V
peak
. Exceeding this value may cause a breakdown in insulation that can
create a shock hazard.
You can make test connections to the Model 2461 from the rear or front panel of the instrument.
Basic connections
The front and rear terminals of the instrument are rated for connection to circuits rated
Measurement Category I only, with transients rated less than 1500 V peak above the
maximum rated input. Do not connect the instrument terminals to CAT II, CAT III, or CAT IV
circuits. Connection of the instrument terminals to circuits higher than CAT I can cause
damage to the equipment and expose the operator to hazardous voltage.
Do not exceed the maximum allowable voltage differentials. Exceeding the voltage
differentials can result in electric shock and damage to the equipment.
Common mode voltage must be externally limited to 250 V DC, 1.05 A maximum.
Failure to limit the common mode voltage can result in electric shock and damage to the
equipment.

Keithley 2461 Specifications

General

Brand	Keithley
Model	2461
Category	Measuring Instruments
Language	English