Simpson 270 Series - Page 46

Operation
. Turn power ON.
Read the current on the black DC scale. Use the 0-50 figures
to read directly in microamperes.
. Turn power OFF and restore circuit to original condition.
NOTE: For polarity reversing see paragraph 4.3.
4.16 DIRECT CURRENT MEASUREMENT 0-1mA
THROUGH 0-500mA RANGE
. Set the function switch at +DC (Figure 4-7).
. Plug the black test lead into the - COMMON jack and the red
test lead into the + jack.
Set the range switch at one of the four range positions marked
1 mA, 10 mA, 100 mA or 500 mA.
. Turn power OFF. Then discharge any capacitors in the circuit.
. Open the grounded side of the circuit in which the current is
being measured. Connect the VOM in series with the circuit.
Connect the red test lead to the positive side and the black
test lead to the negative side.
Turn the power on. Read the current in milliamperes on the
black DC scale. For the 1mA range, use the 0-10 figures and
divide by 10. For the 10mA range, use the 0-10 figures di-
rectly. For the 100mA range, use the 0-10 figures and multi-
ply by 10. For the 500mA range, use the 0-50 figures and
multiply by 10.
g. Turn the power off and disconnect the test leads.
h. Restore circuit to original condition.
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