ABB RET670 Product Manual page 75

ABB
Transformer protection RET670
Customized
Product version: 1.2
Scheme communication
Table 70. Scheme communication logic for residual overcurrent protection ECPSCH
Function
Scheme type
Communication scheme
coordination time
Table 71. Current reversal and weak-end infeed logic for residual overcurrent protection ECRWPSCH
Function
Operating mode of WEI logic
Operate voltage 3U for WEI trip
o
Reset ratio
Operate time for current reversal
logic
Delay time for current reversal
Coordination time for weak-end
infeed logic
Range or value
Permissive Underreaching
Permissive Overreaching
Blocking
(0.000-60.000) s
Range or value
Off
Echo
Echo & Trip
(5-70)% of UBase
>95%
(0.000-60.000) s
(0.000-60.000) s
(0.000–60.000) s
1MRK 504 117-BEN D
Accuracy
-
± 0.5% ± 10 ms
Accuracy
-
± 0.5% of U
r
-
± 0.5% ± 10 ms
± 0.5% ± 10 ms
± 0.5% ± 10 ms
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