VAMP Ltd
Over-, under-, residual voltage and
frequency relay
Technical description
VAMP 135
VM135.EN008
VAMP 24h support phone : +358 (0)20 753 3264
7
2.2.
Relay protection configurations
The relay comprises three different protection configurations:
•
Overvoltage, undervoltage, residual voltage and frequency
supervision with phase voltage measurement. U
mode
: Phase.
•
Overvoltage, undervoltage and frequency supervision with
line voltage measurement. U
mode
: Line.
•
Overvoltage, undervoltage, residual voltage and frequency
supervision with two line voltage measurements and
residual voltage measurement. U
mode
: Line + U
0
.
The configuration mode is selected from the SCALING/ U
mode
:
menu, see Chapter 5.4 in the Operation and configuration
instructions.
2.2.1.
Protection configuration Phase
SCALING/U
mode
: Phase
•
The relay is connected to the phase voltages U
L1
, U
L2
and
U
L3
, see Figure 3.1-1. The line voltages are calculated based
on the measured phase voltages.
•
The setting values of the overvoltage and undervoltage
limits are relative to the rated line voltage U
N
(100% = U
N
x
U
N
= ÷3 x U
VT
. U
VT
= voltage transformers primary voltage
which is defined by the user in the configuration).
•
The residual voltage is calculated from the measured phase
voltages. A separate broken-delta transformer is not
required.
•
The setting values of the residual voltage limits are relative
to the secondary voltage VT
secondary
(100% = VT
secondary
),
which is defined by the user.
2.2.2.
Protection configuration Line
SCALING/Umode: Line
•
The relay is connected to the line voltages U
12
, U
23
and U
31
,
see Figure 3.2-1.
•
The setting values of the overvoltage and undervoltage
limits are relative to the rated line voltage U
N
(100% = U
N
).
U
N
= voltage transformers primary voltage VT
primary
which
is defined by the user.
•
The residual voltage stages U
0
> and U
0
>> are not in use.
