13
The overvoltage stage protects the motors and
transformers connected to the busbars. The
overvoltage stage can be given inverse time
characteristic. When the characteristic curve B
is selected the start voltage can be set relatively
high without rendering to long an operate time
at severe overvoltage.
The overvoltage stage and the undervoltage
stage are both used for tripping. The trip signal
of the undervoltage stage is routed to the circuit
breakers of the motor feeders. The overvoltage
stage operates the main circuit breaker.
The selector switches of the voltage relay SPAU
130 C can be set as follows:
Switch SG1/SPCU 3C14 SGB/SPCU 3C14 SGR
1 0 three-phase 0 not in use 1 control signal from minia-
ture circuit breaker (MCB)
2 1 U> start time = 30 s 0 not in use 0 no start signal of stage U<
to output relay D
3 1 U> inverse charact. 0 not in use 0 no start signal of stage U>
to output relay D
4 1 0 not in use 1 trip signal of stage U< to
curve B output relay D
5 0 1 blocking of stage t< 0 no trip signal of stage U<
to output relay C
6 0 U< stage blocked, 0 not in use 0 no trip signal of stage U<
if U < 20% x U
n
to output relay A
7 0 U< start time = 0.1 s 0 not in use 1 trip signal of stage U> to
output relay C
8 0 t< = 10...12 s 0 not in use 0 no trip signal of stage U> to
output relay B
Σ 14
When the switches are set as above, the output
relays of the voltage relay SPAU 130 C provide
the following signals:
Contact Function
65-66 Tripping of the main circuit breaker (U>)
68-69 Tripping of the circuit breakers of the motor feeders (U<)
80-81 Signal on tripping of the main circuit breaker (U>)
77-78 Signal on tripping of the circuit breakers of the motor feeders (U<)
70-71-72 Self-supervision signal
To Next Page
Loading...
