ABB RELION 670 Series Technical Manual page 615

1MRK 502 066-UUS B
Pickup1
PU_ST1
TRST1
tReset1
t1
ANSI10000040 V3 EN-US
Figure 328: Example for Definite Time Delay stage1 operation
9.1.7.3 Blocking
It is possible to block Two step undervoltage protection UV2PTUV (27) partially or completely, by
binary input signals or by parameter settings, where:
BLOCK:
BLKTR1:
BLK1:
BLKTR2:
BLK2:
If the measured voltage level decreases below the setting of
step 1, or both the trip and the PICKUP outputs of step 1, are blocked. The characteristic of the
blocking is set by the
resulting in no voltage based blocking. Corresponding settings and functionality are valid also for
step 2.
In case of disconnection of the high voltage component the measured voltage will get very low.
The event will PICKUP both the under voltage function and the blocking function, as seen in figure
329. The delay of the blocking function must be set less than the time delay of under voltage
function.
Technical manual
blocks all outputs
blocks all trip outputs of step 1
blocks all pickup and trip outputs related to step 1
blocks all trip outputs of step 2
blocks all pickup and trip outputs related to step 2
IntBlkSel1 parameter. This internal blocking can also be set to Disabled
ANSI10000040-3-en.vsd
IntBlkStVal1 , either the trip output of
Section 9
Voltage protection
M15326-20 v7
609