VAMP 257
Feeder and motor manager
Technical description
VAMP Ltd
144
VAMP 24h support phone : +358 (0)20 753 3264
VM257.EN002
5.3.6.
Frequency protection
Overfrequency and underfrequency protection stages f><
and f>><<
Frequency measuring range
46.0 - 70.0 Hz
Definite time function:
-operating time
0.10
**)
– 300.0 s (step 0.02 s)
Starting time
80 ms
Reset time
100 ms
Reset ratio (f> and f>>)
0.998
Reset ratio (f< and f<<)
1.002
Inaccuracy:
- starting
±20 mHz
- operating time
±1% or ±30 ms
**) This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.
Underfrequency stages f< and f<<
Underfrequency measuring range
40.0 - 64.0 Hz
Definite time function:
-operating time
0.10
**)
- 300.0 s (step 0.02 s)
Undervoltage blocking
2 – 100 %
Starting time
80 ms
Reset time
100 ms
Reset ratio
1.002
Inaccuracy:
- starting
±20 mHz
- operating time
±1% or ±30 ms
**) This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.
5.3.7.
Second harmonic function
2. Harmonic stage / Inrush (68)
Settings:
- Setting range 2.Harmonic
10 – 100 %
- Operating time
0.05** – 300.00 s (step 0.01 s)
**) This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.
5.3.8.
Rate of change of frequency df/dt protection
(81R)
ROCOF stage df/dt 81R
Pick-up setting df/dt
0.2 – 10.0 Hz/s (step 0.1 Hz/s)
Definite time delay (t> and t
Min
> are equal):
- operating time t>
0.14
**)
– 10.00 s (step 0.02 s)
Inverse time delay (t> is more than t
Min
>):
- minimum operating time t
Min
> 0.14
**)
– 10.00 s (step 0.02 s)
Starting time
140 ms
Reset time
t>
Inaccuracy:
- starting
±0.1 Hz/s
- operating time(overshoot
≥
0.2 Hz/s)
±1% or ±30 ms
**) This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.
