Technical description
4 Measurement functions
4.6 Maximum values of the last 31
days and twelve months
VM50.EN004
VAMP 24h support phone +358 (0)20 753 3264
141
4.6.
Maximum values of the last 31 days
and twelve months
Some maximum and minimum values of the last 31 days and
the last twelve months are stored in the non-volatile memory of
the relay. Corresponding time stamps are stored for the last 31
days. The registered values are listed in the following table.
Measurement
Max
Min
Description
IL1, IL2, IL3
X
Phase current (fundamental frequency value)
Io1 X
Residual
current
S X
Apparent
power
P X
X
Active
power
Q X
X
Reactive
power
The value can be a one cycle value or an average according
parameter "Timebase".
Parameters of the day and month registers
Parameter Value
Description
Set
Timebase
20 ms
200 ms
1 s
1 min
demand
Parameter to select the type of the
registered values.
Collect min & max of one cycle values
*)
Collect min & max of 200 ms average
values
Collect min & max of 1 s average values
Collect min & max of 1 minute average
values
Collect min & max of demand values
(see chapter 4.4)
S
ResetDays
Reset the 31 day registers
S
ResetMon
Reset the 12 month registers
S
*) This is the fundamental frequency rms value of one cycle updated every
20 ms.
4.7.
Voltage measurement modes
Depending on the application and available voltage
transformers, the relay can be connected either to zero-
sequence voltage, one line-to-line voltage or one phase-to-
ground voltage. The configuration parameter "Voltage
measurement mode" must be set according the used connection.
The available modes are:
"U
0
"
The device is connected to zero sequence voltage.
Directional earth fault protection is available. Line voltage
measurement, energy measurement and over- and
undervoltage protection are not possible (see Figure 4.7-1