Woodward HighPROtec MCDLV4, Руководство пользователя

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Protective Elements
V/f> - Volts/Hertz [24]
Available Elements
V/f>[1] ,V/f>[2]
This protective element of the device provides over-excitation protection for the generator and unit connected
transformers. It incorporates two elements that can be programmed to specific times and used to create traditional,
two-step over-excitation protection.
In addition, the protective elements can be programmed as inverse time elements to provide advanced protection
by approximating closely the combined generator/unit transformer over-excitation curve. Standard inverse time
curves can be selected along with a linear reset rate that may be programmed to match the specific machine
cooling characteristics.
The percent pickup is based on the Nominal Voltage and Frequency settings. The V/Hz function provides reliable
measurements of V/Hz up to 200% for a frequency range of 5 - 70 Hz.
Characteristic / Curve Shape: INV A
761 MCDLV4 DOK-HB-MCDLV4-2E
1 1.2 1.4 1.6 1.8 2
0.01
0.1
1
10
100
1000
10
3
1
0.3
0.1
Ti
m
e
To
T
rip
[s
]
Multiples of volts per hertz pickup
t-m
ul
tip
lie
r
t =
t-multiplier
-1
2 ( )
V / Vn
V/f>
f / fN