Operator`s manual

1.0 Introduction
Congratulations! You have purchased a Personal Computer (PC) Plug-in instrument with analog and systems
performance that rivals the best, all-in-one box, instruments. The SM2040 series digital multimeters (DMMs) are
easy to setup and use, have sophisticated analog and digital circuitry to provide very repeatable measurements, and
are protected to handle any unexpected situations your measurement environment may encounter. To get years of
reliable service from these DMMs, please take a few moments and review this manual before installing and using
this precision instrument.
This manual describes the SM2040, SM2042 and SM2044 DMMs. Each DMM delivers unmatched breakthrough
performance in a PCI plug-in instrument. With a rich repertoire of functions, the SM2040 series out performs all
other plug-in DMMs, including the trusted Signametrics SM-2020CT, and most brand named bench top units.
Note: In this manual, all references to the "SM2040" and “DMM” apply to the SM2040, SM2042 and SM2044.
Features unique to the SM2042 and SM2044 will be identified as such.
1.1 Safety Considerations
Safety Considerations
The SM2040 series of DMMs is capable of measuring up to 300 VDC or 250 VAC across the Volt HI and
LO terminals, and can also measure common mode signals that "float" the DMM above EARTH ground
by up to 300 VDC or 250 VAC. When making common mode measurements, the majority of the circuits
inside the DMM are at the common mode voltage. These voltages can be lethal and can KILL! During
and after installing your DMM, check to see that there are no wires or ribbon cables from your PC
trapped inside the DMM.
The DMM comes installed with four shields (bottom, top and two edge strips) that must not be removed
for performance as well as safety reasons. Removal of these shields and/or improper assembly of the
shields can result in lethal voltages occurring within your PC. Be sure to check your installation before
closing the cover on your personal computer.
Warning
Check to see that no loose wires or ribbon cables infringe upon any of the internal circuits of the
DMM, as this may apply measurement voltages to your computer, causing electrocution and/or
damage to your computer!
To avoid shock hazard, install the DMM only into a computer that has its power connector
connected to a power receptacle with an earth safety ground.
When making any measurements above 50 VDC or 40 VAC, only use Safety Test Leads. Examples
of these are the Signametrics Basic Test Leads and Deluxe Test Leads, offered as an accessory with the
Signametrics DMMs.
7 Signametrics