ABB 615 Series - Page 1130

Frequency adaptation starts when the generator terminal positive-sequence voltage level
exceeds 0.04 xUn (minimum level). As the Synchronism and energizing check (25) bus
voltage U12b voltage input always expects Rated frequency, the frequency adaptivity
does not apply for this input.
If the generator terminal positive-sequence voltage is below the minimum level, the relay
is not able to maintain frequency adaptation. The non-adaptive situation is indicated by
function PROTECTION output FRQ_ADP_FAIL. The tracked frequency is retained for
3 seconds until the FRQ_ADP_FAIL output is activated and Rated frequency is expected.
The FRQ_ADP_FAIL output can be utilized in the application configuration, if
necessary.
The operation accuracy of the protection functions in the range of 0.2...1.5 xFn can be
assumed to be according to the technical data given separately for each function. Operate
time accuracy and reset times given in technical data are only valid in the frequency range
specified for each function. Typical operate time examples at low frequencies are given in
Table.
Table 948: Protection operate time examples at low frequency
Function Characteristic
Value
1)
51P, 50P Trip delay time = 40 ms
I
Fault
= 1.1 × set Pickup value , 10 Hz
Measurement mode = “RMS” or “DFT”
Measurement mode = “Peak-to-Peak”
Typically 130 ms
Typically 110 ms
Trip delay time = 40 ms
I
Fault
= 2.0 × set Pickup value , 12 Hz
Measurement mode = “DFT” Typically 85 ms
Trip delay time = 40 ms
I
Fault
= 2.0 × set Pickup value , 20 Hz
Measurement mode = “DFT” Typically 70 ms
50P-3 Trip delay time = 20 ms
Measurement mode = “P-to-P+backup”
I
Fault
= 1.1 × set Pickup value , 10 Hz
I
Fault
= 2.0 × set
Pickup value , 10 Hz
Typically 45...100 ms
Typically 20...40 ms
67/51N, 67/50N Trip delay time = 50 ms
I
Fault
= 2.0 × set Pickup value , 10 Hz
Measurement mode = “DFT”
Typically 110 ms
50N, 50G Trip delay time = 40 ms
I
Fault
= 2.0 × set Pickup value , 10 Hz
Measurement mode = “DFT”
Typically 100 ms
Table continues on next page
Section 11 1MAC059074-MB A
General function block features
1124 615 series ANSI
Technical Manual