HT Instruments HT7 Bedienungsanleitung Seite 29

5.5. PHASE SEQUENCE INDICATION
• The maximum input for AC voltage is 440V. Do not measure higher
voltages to avoid risks of electrical shocks or serious damages to the
instrument.
•
>40VAC , even if the batteries are low or have been removed.
1. Perform the preliminary Autotest (see § 4.3).
2. Connect the L1 probe to phase 1 and the L2 probe to phase 2 of the three-phase
system under test (see Fig. 6). The measurement is performed only when probes are
in contact to live conductors.
3. The instrument turns automatically on and the measured AC voltage value is displayed
both in numerical and bargraph
The "
4. symbol is shown on the display for Phase-Neutral AC voltage measurement
"
from 180V to 440V,
5. symbol (clockwise) or
the phase sequence detected.
6. Connect the L1 probe to phase 2 and the L2 probe to phase 3 of the three-phase
system under test.
displayed according to the phase sequence detected.
7. Connect the L1 probe to phase 2 and the L2 probe to phase 3 of the three-phase
system under test.
displayed according to the phase sequence detected.
8. Press the key to switch on the white LED illuminator to perform measurements in
dark environments.
symbol is lighted up whenever the voltage between the probes is
Fig. 6: Phase sequence test
modes.
50/60Hz.
symbol (counterclockwise) are displayed according to
symbol (clockwise) and
symbol (clockwise) and
CAUTION
symbol (counterclockwise) are
symbol (counterclockwise) are
EN - 10
HT7