Crown CT44051 Manual Original página 6

2. Long press to turn on the illumination function and the backlight at the same time. Short
press the key again to turn off the illumination function. It turns off automatically with no
operation for 30S.
Auto power off
After about 15 minutes after power on, if there is no operating instrument, it will give audible
voice prompts, will automatically cut off the power, enter the hibernation mode, in the automatic
shutdown mode, any key can be restarted.
ACV and DCV measurement
Do not measure any voltage greater than 600V to prevent electric shock or damage to the
instrument.
Do not apply more than 600V voltage between the common and earth to prevent electric
shock or damage to the instrument.
ACV or DCV measuring:
1. Turn the switch to or .
2. Connect the black test pen to the COM jack and the red pen to the V jack.
3. Measure the voltage value of the circuit under test with the other two ends of the test pens.
4. The reading will be shown on the LED display as well as the polarity of the end connected with
the red lead.
Notes:
*The meter shows readings in range DCV 200mV and 2V even there is no input voltage or test
pens connection. Then short circuit
*Please change to a higher range if the "OL" is shown .
Resistance measurement
To avoid damage to the meter or device under test, all power to the circuit under test
should be cut off before measuring resistance, and all high
be fully discharged.
Resistor measuring:
1. Rotate the rotary switch to the proper position.
2. Connect the black test pen and the red test pen to the "COM" input socket and
socket 3.Uses the test pen to test the resistance value of the circuit.
4. The resistance value shows on the display window .
Notes:
*The resistance value measured on the circuit is usually different from the resistance rating.
*To measure the low resistance accurately, please short-circuit the two test pens to read out the
short-circuit resistance of the test leads, and subtract it by the readings to get accurate resistance
value.
and "COM" to make the meter shows zero.
- voltage capacitors should
English
9
*At 20megohms range, the reading will stabilize after a few seconds, which is normal for high
resistance measurements.
*When the meter is not in circuit, the display will show "OL", indicating that the measurement
value is out of the measurement range.
Diode m easurement
To avoid damage to the meter or device under test, all power to the circuit under test
should be cut off before measuring diode, and all high
discharged.
Test a diode outside the circuit.：
1. Turn the rotary switch to
2. Connect the black test pen and the red test pen to the "COM" input socket and " V/Ω" input
socket
3. Connect the black test pen and red test pen to the negative and positive electrodes of the
diode under test.
4. The meter will display the forward bias value of the diode under test. If the polarity is reversed,
then it shows 'OL' .
The normal diode in the circuit still produces a forward voltage drop of 0.5V to 0.8V, but the
reverse bias reading will depend on the variety of the resistance value of the other channels
between the two test pens.
Buzzer test
To avoid damage to the meter or device under test, all power to the circuit under test
should be cut off before measuring on
should be fully discharged.
For on-off state of the circuit:
1. Turn the rotary switch to
2. Connect the black test pen and the red test pen to the "COM" input socket and
input
socket
3. Measure the resistance of the circuit under test at the other end of the test pens. If the
resistance of the circuit under test is not greater than about 30 ohms, the indicator light will turn
on and the buzzer will sound continuously.
- voltage capacitors should be fully
position.
- off of the circuit and all high -
position.
English
10
voltage capacitors
input