Ac Current (Frequency, Duty Cycle) Measurements - Sonel CMM-40 Manual De Uso

5.5 AC current (frequency, duty cycle) measure-
ments
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 AC 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 4000µA AC, 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 AC, 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 AC, 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 "AC" 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 neutral side of the circuit.
Touch the red test probe tip to the "hot" side of the circuit,

Apply power to the circuit,

Read the current in the display. In the 10AAC range, right aux-
iliary display frequency,

Press and hold the MODE button to indicate "Hz",

Read the frequency in the display,

Momentarily press the MODE button again to indicate "%",

Read the % duty cycle in the display,

Press and hold the MODE button to return to current meas-
urement,
ATTENTION!
CMM-40 – USER MANUAL
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