2 Operation of the analyzer
19
Tab. 3. Approximate recording times for a few typical configurations.
Configuration
mode/profile
Averaging
time
System
type
(current
measure-
ment on)
Events
Event wave-
forms
Waveforms
after averag-
ing period
Approximate
recording
time with 2GB
allocated
space
according to EN
50160
10 min
3-phase
wye
(1000 events)
(1000 events)
60 years
according to the
"Voltages and
currents" profile
1 s
3-phase
wye
270 days
according to the
"Power and har-
monics" profile
1 s
3-phase
wye
23 days
according to the
"Power and har-
monics" profile
1 s
3-phase
wye
(1000 events)
(1000 events)
22.5 day
all possible pa-
rameters
10 min
3-phase
wye
4 years
all possible pa-
rameters
10 s
3-phase
wye
25 days
all possible pa-
rameters
10 s
1-phase
64 days
all possible pa-
rameters
10 s
1-phase
(1000 events
/ day)
(1000 events /
day)
22 days
2.9
Measuring arrangements
The analyzer may be connected directly and indirectly to the following types of networks:
1-phase (Fig. 5),
2-phase (split-phase) with split-winding of the transformer (Fig. 6),
3-phase wye with a neutral conductor (Fig. 7),
3-phase wye without neutral conductor (Fig. 8),
3-phase delta (Fig. 9).
In three-wire systems, current may be measured by the Aron method, which uses only two
clamps that measure linear currents I
L1
and I
L3
. I
L2
jest current is then calculated using the following
formula:
𝐼
𝐿2
= −𝐼
𝐿1
− 𝐼
𝐿3
This method can be used in delta systems (Fig. 10) and wye systems without a neutral conduc-
tor (Fig. 11).
Note
As the voltage measuring channels in the analyzer are referenced to N
input, then in systems where the neutral is not present, it is necessary to
connect N input to L3 network terminal. In such systems, it is not required
to connect L3 input of the analyzer to the tested network. It is shown in
Fig. 8, Fig. 9, Fig. 10 and Fig. 11 (three-wire systems of wye and delta
type).
Summary of Contents for PQM-700
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