Sonel CMM-40, User Manual

Page: 56 / 112

CMM-40
– USER MANUAL
54
5.4 DC current measurements
ATTENTION!
Do not make 20A current measurements for longer than 30
seconds. Exceeding 30 seconds may cause damage to the
meter and/or the test leads.
In order to realise a measurement of DC current, it is necessary
to realise the following actions:

Insert the black test lead banana plug into the negative COM
jack,

For current measurements up to 4000
µA DC, set the function
switch to the
µA
position and insert the red test lead banana
plug into the
µA/mA
jack,

For current measurements up to 400mA DC, set the function
switch to the
mA position and insert the red test lead banana
plug into the
µA/mA
jack,

For current measurements up to 20A DC, set the function
switch to the
10A/HZ/% position and insert the red test lead
banana plug into the 10A jack,

Press the MODE
button to indicate “
DC
” on the display,

Remove power from the circuit under test, then open up the
circuit at the point where you wish to measure current,

Touch the black test probe tip to the negative side of the cir-
cuit. Touch the red test probe tip to the positive side of the cir-
cuit,

Apply power to the circuit,

Read the current in the display,

Having done the measurement disconnect the test leads from
the meter.