Fluke 87 III - Manual (Page 32)

80 Series III
Users Manual
24
3. If you are using the A terminal, set the rotary switch to
mA/A. If you are using the mA/
µ
A terminal, set the
rotary switch to
µ
A for currents below 4000
µ
A
(4 mA), or mA/A for currents above 4000
µ
A.
4. To measure ac current, press the blue button.
5. Break the circuit path to be tested. Touch the black
probe to the more negative side of the break; touch
the red probe to the more positive side of the break.
Reversing the leads will produce a negative reading,
but will not damage the meter.
6. Turn on power to the circuit; then read the display. Be
sure to note the unit given at the right side of the
display (
µ
A, mA, or A).
7. Turn off power to the circuit and discharge all high-
voltage capacitors. Remove the meter and restore the
circuit to normal operation.
The following are some tips for measuring current:
•
If the current reading is 0 and you are sure the meter
is set up correctly, test the meter’s fuses as described
under "Testing the Fuses".
•
A current meter drops a small voltage across itself,
which might affect circuit operation. You can calculate
this burden voltage using the values listed in the
specifications in Table 14.