HT Italia VEGA 76, User Manual

Page: 44 / 60

VEGA 76
EN - 42
11.3. USING THE INSTRUMENT IN A THREE PHASE 3 WIRE SYSTEM
CAUTION
The maximum voltage between B1 and B4 inputs is 600 V~ (CATII) / 350V~
phase – earth or 600V~ (CATIII) / 300 V~ phase to earth.
Do not measure voltages exceeding the limits prescribed by this manual.
Should you exceed the voltage limits you could damage the instrument
and/or its components or endanger your safety.
L1
L2
L3
RED
BLUE
BLACK
GREEN
Fig. 3: Instrument connection in a 3-wire three-phase system
CAUTION
•
Please note that in this case the blue cable is connected to the green
cable on phase 2.
•
If possible, before connecting the instrument to the electrical equipment
to be tested take the power supply off the electrical equipment.
1. Check, and if needed modify, the basic settings of the instrument (see paragraphs 5.2
and 5.3). Particularly, the 3-wire mode must be set.
2. Rotate the switch to the position corresponding to the type of analysis desired. In case
of doubts select POWER (see paragraph 6.3).
3. Connect the phase and neutral voltage wires following the connections shown in Fig. 3.
4. If you want to measure current and power, connect the clamp meter to the phase
conductor respecting the specifications shown on the clamp and the connections
shown in the picture. In case of doubts set
temporarily the 3PH4W mode, then select
POWER , connect the blue wire of the instrument to earth and, connecting one clamp at
a time, check if:
a) The phase sequence is correct (see paragraph 6.1.2).
b) The active power P of each phase is positive. If negative, turn the clamp of the phase in
question.
c) The value of the Pf of each phase is not excessively low (typically it’s not lower than 0.4). In
case the Pf is lower than 0.4, check if the phase voltage is associated to the right clamp
meter (for example the voltage of phase 1 must be associated to the clamp meter no. 1).
d) After checking, and if needed modifying, the connection of the instrument to the equipment
re-set the 3-wire mode and the connections shown in the picture (blue and green wire
together).
5. Apply voltage to the electrical equipment under test (if previously shut off for the
instrument connection).
6. The values of the available electrical parameters will be displayed of the instrument.
For further details see the paragraph relevant to the position of the switch.
7. You can press HOLD to interrupt the updating in real time of the displayed values.
8. If you want to record:
a) Check and eventually modify the values of the basic parameters (see paragraphs 5.2 and
5.3).
b) Check and eventually modify the recording parameters by pressing MENU (see the
paragraph corresponding to the position of the rotary switch selected).
c) To start the recording press START (see chapter 6).