User manual

8 Carrying out a test
23
Removing/installing the probe tip protector/extension
The probe tip protector and extension can be removed/installed as required.
Attention: Use of the probe tip protector may be required depending on the
national regulations or provisions!
> Probe tip protector: push onto probe tips or pull off.
> Probe tip extension: screw onto probe tips or unscrew.
8.2. Voltage testing
> Connect both probe tips to the test object.
- The instrument switches on automatically at a voltage of approximately
6 V or above.
- The voltage is shown in the LC display.
- In the case of DC voltage, the polarity of the indicated voltage relates
to the voltage tester probe tip.
- When the safety extra-low voltage is reached or exceeded (50 V AC /
120 V DC), an acoustic signal is emitted, the red LED comes on and
is illuminated in the LC display.
8.3. Single pole phase testing (only testo 755-
2)
Single pole phase testing is possible as from AC voltages of approx. 90 V.
During single pole phase testing to determine external conductors, the
display function may be impaired, for example due to insulating personal
protective equipment or other insulators.
Single pole phase testing is not suitable for testing for absence of voltage.
Two-pole voltage testing is required for this.
> Connect a probe tip of the voltage tester to the test object.
- is illuminated to signify phase testing on the relevant conductor.
8.4. Current measurement
Strong interferences in the vicinity result in an unstable display and
measurement errors.
✓ No voltage must be applied to the probe tips, so that the instrument
switches to current measurement mode.
> Push the instrument's fork over the live conductor as far as the sensor
zone.
- The reading is shown in the LC display.
8.5. Continuity/resistance testing
✓ Disconnect the test circuit/object from the power supply.
✓ Conduct a two-pole voltage test on the test object to confirm the
absence of voltage.
> Connect both probe tips to the test object.
- For continuity up to approx. 30 , an acoustic signal is emitted, for
resistance up to approx. 100 k the acoustic alarm remains inactive.
- The instrument switches off automatically after 10 seconds if no
continuity/resistance is detected. As soon as continuity/resistance is
detected, the instrument switches back on automatically.