29
NV10P - Manual - 01 - 2015
CHARACTERISTICS
4.3 I/O
DESCRIPTION
Metering inputs
VTs versions
The following inputs are provided:
Three phase voltage inputs with programmable nominal voltages within range 50...130 V (
U
R
=100 V)
or 200...520 V (
U
R
=400 V) to be select on order. The nominal voltages is user adjustable inside a
wide setting range, so the relays can be employed on plants with TV different secondary voltages
(50...130 V for versions with
U
R
=100 V and 200...520 V for versions with
U
R
=400 V). The version with
U
R
=400 V allows a direct measure without interposing VTs for low voltage applications (200...520 V
nominal voltage).
One residual voltage input, with programmable nominal voltage within range 50...130 V (
U
ER
=100 V);
Electronic sensor versions
Three voltmetric inputs are provided; the phase voltages
U
L1
,
U
L2
,
U
L
are measured, and the phase-to-
phase voltages
U
12
,
U
23
,
U
31
and the residual voltage
U
EC
are calculated.
Signal processing
Various processing levels are involved:
Acquisition (base level).
Direct measures of physical channels (fi rst level).
Calculated measures (second level).
Derived (third level).
The measures concerning a level are based on data worked out in the previous level.
For each level the required resources concerning the priority for tasks (conditioning circuits, DSP
and CPU) are on hand.
ACQUISITION (base level)
The input signals are sampled 24 times per period:
-
u
L1
...
u
L3
Input voltage instantaneous values
-
u
E
Residual voltage instantaneous value
From the sampled quantities, several measures are computed for protection, monitoring and meter-
ing purposes.
Direct
Calculated
•
•
•
•
•
•
•
•
sensori-en.ai
3 line voltage inputs
NV10P
1 residual voltage input
sensori-en.ai
3 line voltage inputs
NV10P
1 residual voltage input
V-sensor1.ai
3 phase voltage inputs
NV10P
V-sensor1.ai
3 phase voltage inputs
NV10P
acquisizione-en.ai
ACQUISITION
INSTANTANEOUS MEASURES
≈
acquisizione-en.ai
ACQUISITION
INSTANTANEOUS MEASURES
≈
