9.25
Date Code 20080213 Instruction Manual SEL-351A Relay
Setting the Relay
Relay Word Bits (Used in SEL
OGIC Control Equations)
21 59S2
b
Channel VS instantaneous overvoltage element (channel VS voltage
above pickup setting 59S2P; see Figure 3.26)
59VP
b
Phase voltage window element [selected phase voltage (VP) between
threshold settings 25VLO and 25VHI; see Figure 3.27]
Testing
59VS
b
Channel VS voltage window element (channel VS voltage between
threshold settings 25VLO and 25VHI; see Figure 3.27)
SF
b
Slip frequency between voltages VP and VS less than setting 25SF
(see Figure 3.27)
25A1
b
Synchronism check element (see Figure 3.28) Control
25A2
b
Synchronism check element (see Figure 3.28)
3P27 Three-phase undervoltage (see Figure 3.22 and Figure 3.24)
3P59 Three-phase overvoltage (see Figure 3.22 and Figure 3.24)
22 81D1 Level 1 instantaneous frequency element
(with corresponding pickup setting 81D1P; see Figure 3.32)
Testing
81D2 Level 2 instantaneous frequency element
(with corresponding pickup setting 81D2P; see Figure 3.32)
81D3 Level 3 instantaneous frequency element
(with corresponding pickup setting 81D3P; see Figure 3.32)
81D4
b
Level 4 instantaneous frequency element
(with corresponding pickup setting 81D4P; see Figure 3.32)
81D5
b
Level 5 instantaneous frequency element
(with corresponding pickup setting 81D5P; see Figure 3.32)
81D6
b
Level 6 instantaneous frequency element
(with corresponding pickup setting 81D6P; see Figure 3.32)
27B81 Undervoltage element for frequency element blocking (any phase voltage
below pickup setting 27B81P; see Figure 3.30 and Figure 3.31)
50L Phase instantaneous overcurrent element for load detection (maximum
phase current above pickup setting 50LP; see Figure 5.3)
23 81D1T Level 1 definite-time frequency element 81D1T timed out
(derived from 81D1; see Figure 3.32)
Tripping, Control
81D2T Level 2 definite-time frequency element 81D2T timed out
(derived from 81D2; see Figure 3.32)
81D3T Level 3 definite-time frequency element 81D3T timed out
(derived from 81D3; see Figure 3.32)
81D4T
b
Level 4 definite-time frequency element 81D4T timed out
(derived from 81D4; see Figure 3.32)
81D5T
b
Level 5 definite-time frequency element 81D5T timed out
(derived from 81D5; see Figure 3.32)
81D6T
b
Level 6 definite-time frequency element 81D6T timed out
(derived from 81D6; see Figure 3.32)
VPOLV Positive-sequence polarization voltage valid (see Figure 4.21)Testing
LOP Loss-of-potential (see Figure 4.1) Testing, Special directional
control schemes
Table 9.6 Relay Word Bit Definitions for SEL-351A (Sheet 8 of 16)
Row Bit Definition Primary Application
Courtesy of NationalSwitchgear.com
To Next Page
Loading...