9424200996
5-1
BE1-11
m
Phase Undervoltage (27P) Protection
5 • Phase Undervoltage (27P) Protection
Four phase undervoltage (27P) elements monitor the sensing voltage applied to the BE1-11
m
. An
element can be configured to protect against undervoltage when the phase voltage decreases below a
defined level.
The four, identical phase undervoltage protection elements are designated 27P-1, 27P-2, 27P-3, and
27P-4. Element logic connections are made on the BESTlogic
™
Plus
screen in BESTCOMS
Plus
®
and
element operational settings are configured on the Undervoltage settings screen in BESTCOMS
Plus
. A
summary of the logic inputs and outputs and operational settings appears at the end of this chapter.
BESTCOMS
Plus
Navigation Path:
Settings Explorer, Protection, Voltage, Undervoltage (27P)
HMI Navigation Path:
Settings Explorer, Protection, Settings Group x (where x = 0 to 3), Voltage
Protection, Undervoltage 27P
Element Operation
Phase undervoltage protection can be used to prevent large transformer and equipment damage when an
undervoltage condition exists. For example, an undervoltage condition could occur when a tap changing
control fails.
Modes of Protection
Three modes of protection are available. The One of Three mode activates protection when one of the
three phases of voltage decreases below the Pickup setting. The Two of Three mode activates protection
when any two of the three phases of voltage decrease below the Pickup setting. The Three of Three
mode activates protection when all three phases of voltage decrease below the Pickup setting.
Voltage Response
The phase undervoltage element can be set to monitor VPP or VPN. This is determined by the 27/59
Mode
parameter of the phase VT connections found on the System Parameters/Sensing Transformers
settings screen in BESTCOMS
Plus
. For more information on the VTP setup for PP or PN voltage
response, see the
Configuration
chapter.
Timings
The timing mode can be set for definite or inverse.
Inverse
When inverse timing is selected, a Curve setting is provided to select programmable or table curves. The
user can select integrating reset timing to make the protective element use integrated reset and emulate
an electromechanical induction disk reset characteristic. The undervoltage inverse time curve with default
constants is shown in the
Time Curve Characteristics
chapter.
Programmable Curves
The programmable curve can be used to create a custom curve by selecting constants in the inverse time
characteristic equation. When curve P is selected, the constants used in the equation are those defined
by the user. Characteristics for trip and reset programmable curves are defined by Equation 5-1 and
Equation 5-2. Definitions for these equations are provided in Table 5-1.
𝑇𝑇
𝑇𝑇
=
𝐴𝐴𝐴𝐴
𝐶𝐶 − 𝑀𝑀
𝑁𝑁
+
𝐵𝐵𝐴𝐴
Equation 5-1. Time Characteristics for Trip
𝑇𝑇
𝑅𝑅
=
𝑅𝑅𝐴𝐴
|
𝑀𝑀
2
−
1|
Equation 5-2. Time Characteristics for Reset
Summary of Contents for BE1-11m
Page 8: ...vi 9424200996 Revision History BE1 11m...
Page 12: ...x 9424200996 Contents BE1 11m...
Page 21: ...9424200996 1 9 BE1 11m Introduction Figure 1 1 Style Chart...
Page 22: ...1 10 9424200996 Introduction BE1 11m...
Page 40: ...3 6 9424200996 Controls and Indicators BE1 11m Figure 3 3 Front Panel Display Setup Screen...
Page 54: ...5 6 9424200996 Phase Undervoltage 27P Protection BE1 11m...
Page 56: ...6 2 9424200996 Negative Sequence Voltage 47 Protection BE1 11m...
Page 61: ...9424200996 7 5 BE1 11m Phase Overvoltage 59P Protection Figure 7 3 Overvoltage Settings Screen...
Page 62: ...7 6 9424200996 Phase Overvoltage 59P Protection BE1 11m...
Page 68: ...8 6 9424200996 Auxiliary Overvoltage 59X Protection BE1 11m...
Page 80: ...12 4 9424200996 Instantaneous Overcurrent 50 Protection BE1 11m...
Page 84: ...13 4 9424200996 Breaker Failure 50BF Protection BE1 11m...
Page 92: ...14 8 9424200996 Inverse Overcurrent 51 Protection BE1 11m...
Page 105: ...9424200996 18 3 BE1 11m Power Factor 55 Protection Figure 18 2 Power Factor Settings Screen...
Page 106: ...18 4 9424200996 Power Factor 55 Protection BE1 11m...
Page 110: ...19 4 9424200996 Resistance Temperature Detector 49RTD Protection BE1 11m...
Page 118: ...20 8 9424200996 Thermal Curve 49TC Protection BE1 11m...
Page 122: ...22 2 9424200996 Starts per Time Interval 66 Protection BE1 11m...
Page 124: ...23 2 9424200996 Restart Inhibit Protection BE1 11m...
Page 140: ...28 4 9424200996 Breaker Control Switch 101 BE1 11m...
Page 148: ...29 8 9424200996 Setting Groups BE1 11m...
Page 156: ...30 8 9424200996 Metering BE1 11m Figure 30 11 RTD Meter Screen...
Page 158: ...31 2 9424200996 Digital Points BE1 11m Figure 31 2 Digital Points Monitor Screen...
Page 177: ...9424200996 34 5 BE1 11m Motor Reporting Figure 34 9 Learned Motor Data Screen...
Page 178: ...34 6 9424200996 Motor Reporting BE1 11m...
Page 184: ...35 6 9424200996 Alarms BE1 11m...
Page 186: ...36 2 9424200996 Differential Reporting BE1 11m...
Page 196: ...38 4 9424200996 Demands BE1 11m...
Page 198: ...39 2 9424200996 Load Profile BE1 11m...
Page 208: ...41 6 9424200996 Trip Circuit Monitor 52TCM BE1 11m...
Page 212: ...42 4 9424200996 Fuse Loss 60FL BE1 11m...
Page 218: ...43 6 9424200996 BESTnet Plus BE1 11m Figure 43 8 Power Quality Page...
Page 221: ...9424200996 44 3 BE1 11m Mounting Figure 44 3 Case Side Dimensions...
Page 235: ...9424200996 45 5 BE1 11m Terminals and Connectors Figure 45 7 Example of Reversed CT Polarity...
Page 236: ...45 6 9424200996 Terminals and Connectors BE1 11m...
Page 269: ...9424200996 48 15 BE1 11m BESTlogic Plus Figure 48 4 Logic Page 1 for Default Logic...
Page 288: ...49 10 9424200996 Communication BE1 11m Figure 49 14 Modbus Mapping Screen...
Page 306: ...52 4 9424200996 Device Information BE1 11m...
Page 314: ...53 8 9424200996 Configuration BE1 11m Figure 53 3 Display Units Screen...
Page 318: ...54 4 9424200996 Introduction to Testing BE1 11m...
Page 330: ...56 6 9424200996 Commissioning Testing BE1 11m...
Page 336: ...58 4 9424200996 Phase Undervoltage 27P Test BE1 11m...
Page 340: ...59 4 9424200996 Phase Overvoltage 59P Test BE1 11m...
Page 352: ...60 12 9424200996 Auxiliary Overvoltage 59X Test BE1 11m...
Page 360: ...61 8 9424200996 Frequency 81 Test BE1 11m...
Page 364: ...62 4 9424200996 Instantaneous Undercurrent 37 Test BE1 11m...
Page 376: ...63 12 9424200996 Instantaneous Overcurrent 50 Test BE1 11m...
Page 396: ...65 16 9424200996 Inverse Overcurrent 51 Test BE1 11m...
Page 408: ...67 6 9424200996 Power 32 Test BE1 11m...
Page 412: ...68 4 9424200996 Loss of Excitation Reverse Var Based 40Q Test BE1 11m...
Page 426: ...70 10 9424200996 Thermal Curve 49TC Test BE1 11m...
Page 432: ...72 4 9424200996 Starts per Time Interval 66 Test BE1 11m...
Page 436: ...73 4 9424200996 Restart Inhibit Test BE1 11m...
Page 440: ...74 4 9424200996 Virtual Control Switches 43 Test BE1 11m...
Page 450: ...75 10 9424200996 Logic Timers 62 Test BE1 11m...
Page 464: ...79 8 9424200996 Troubleshooting BE1 11m...
Page 480: ...80 16 9424200996 Specifications BE1 11m...
Page 600: ...84 56 9424200996 Settings Calculation Examples BE1 11m Figure 84 70 Logic Page 4 Part 1...
Page 602: ...84 58 9424200996 Settings Calculation Examples BE1 11m...
Page 608: ...85 6 9424200996 BESTCOMSPlus Settings Loader Tool BE1 11m...
Page 609: ......