Keithley 2000-SCAN-20, Instruction Manual

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2-12 Card Connections and Installation
Board soldering and cleaning precautions
NOTE Failure to observe the following precautions may result in degraded card
performance.
When soldering resistors, only touch areas associated with resistor installation and do not
spread flux to other areas of the circuit board. Use solder with an OA (organic activated) flux.
Thoroughly clean the circuit board with pure water after soldering to remove all contaminants.
After cleaning with water, swab the area with pure methanol and allow the board to dry for
several hours in a 50°C environment before use.
Current measurements
Even with the current shunts installed, you cannot make direct current measurements with the
scanner card. Instead, you must close the channel to be measured and measure the voltage across
the shunt. The current can then be calculated as follows:
I = V/R
Where: I = current being determined
V= voltage measured by multimeter
R= shunt resistance value
Instead of manually calculating current, set up a Model 2000-20 mX + b math calculation
function. (Here, m = 1/R and b = 0.). The multimeter will then display the actual current value.
Refer to the multimeter manual for details on using math functions.