SEL-FT50/SEL-FR12 Fault Transmitter and Receiver System Accelerate Tripping, Speed Up Restoration, and Improve Safety on Distribution Feeders SEL-FT50/SEL-FR12 Instruction Manual Fault Transmitter and Receiver System SEL-RP50 not available in all regions need new photo Major Features and Benefits The SEL-FT50/SEL-FR12 Fault Transmitter and Receiver System speeds up distribution-protection schemes by detecting and transmitting distribution feeder fault information to recloser controls or relays.
Functional Overview ➤ Easy Installation. Install the SEL-FT50 and SEL-RP50 on live lines by using familiar line tools and techniques. ➤ Flexible Integration. Install the SEL-FT50/SEL-FR12 system in an existing relay protection system.
Functional Overview 3 The SEL-FT50 and SEL-FR12 contain subsystems outlined in the upper and lower portion of Figure 1, respectively. NOTE: Systems with SEL-FT50s manufactured before May 2021 only support one SEL-RP50 per SEL-FT50. See Appendix D: SEL-RP50 Fault Repeater Detailed Implementation on page 54 for required settings. The SEL-RP50, outlined in the center portion of Figure 1, is available in certain markets.
System Overview System Overview Figure 2 provides an overview of the SEL-FT50/SEL-FR12 system and illustrates how to apply it across a distribution power system. Figure 2 SEL-FT50/SEL-FR12 System -- need updated drawing NOTE: The SEL-RP50 is not available in all markets. See Table 13. The SEL-FT50/SEL-FR12 system components are easy to use, and they contain many powerful and innovative features.
System Overview 5 Each SEL-FT50 mounts onto and monitors the line current on one phase. When a fault occurs, the SEL-FT50 transmits a high-speed wireless signal to influence protection decisions. Control (DIP) switches inside the transmitter allow easy selection of unit and Network IDs. No batteries are needed because the SEL-FT50 is powered by line current.
System Overview ENABLED LED FAULT and LINK status LEDs MIRRORED BITS status LEDs TARGET RESET pushbutton Radio antenna BNC connector Serial port (DB-9 connector) Figure 5 Power supply input (9–30 Vdc) Grounding lug Control (DIP) switches to select: • Network ID—SW 1–4 • Baud rate—SW 5–6 • MIRRORED BITS TX and RX ID—SW 7–10 • Near/distant SEL-FT50—SW 11–14 SEL-FR12 Overview The SEL-FR12 collects wireless signals simultaneously from as many as 12 SEL-FT50 Fault Transmitters (enough for 4 three-
Application Examples Table 1 The ROK, TX, RX (green), and LOOP (red) LEDs indicate MIRRORED BITS status and activity. The ROK LED illuminates when MIRRORED BITS data exchange is successful. ➤ The TARGET RESET pushbutton resets the FAULT LEDs. Press and hold the pushbutton to illuminate all HMI LEDs (lamp test function). Target and Status LED Definitionsa LED (Color) Off FAULT (red) target LINK (green) status a ➤ 7 Flashing On Reset Methods No fault signal has been Not applicable.
Application Examples SEL-FT50 SEL-FT50 SEL-FT50 R Wireless SEL-FT50 SEL-651R-2 Figure 7 SEL-FR12 Recloser Communication With Fault Transmitters Each SEL-FT50 monitors line current and instantly transmits a wireless signal when an overcurrent (fault) condition occurs. The companion SEL-FR12 receives and aggregates fault data from as many as 12 SEL-FT50 Fault Transmitters.
Application Examples 9 Figure 8 gives a representation of a typical time-overcurrent coordination graph. 1,000 Fuse-Clearing Curve Fuse-Melting Curve 100 Recloser Control Slow Curve 10 Time (s) 1 0.1 Recloser Control Fast Curve 0.01 100 Figure 8 1,000 Current (A) Example Time-Overcurrent Element Coordination Fuse-Blowing Scheme Shortcomings For a radial distribution system, the goal of the fuse-blowing scheme is to minimize the number of customers exposed to an interruption.
Application Examples R Figure 9 Fault on Unfused Tap Improve Fuse-Blowing Schemes With the Fault Transmitter and Receiver System With the SEL-FT50/SEL-FR12 system installed as shown in Figure 10, the recloser control receives an indication whenever a fault is on the unfused branch. With this information, if a fault occurs on the unfused line section, the recloser control can trip instantaneously instead of waiting for the fuse delay.
Application Examples 11 The following two example applications show how a single protective zone using the SEL-FT50/SEL-FR12 system allows both fuse-saving and fuse-blowing schemes in service. Example 1: Switchover Without Interruption From a Fuse-Blowing Scheme to a Fuse-Saving Scheme In this switchover scheme, utilities have the option to tailor protection for specific line segments with different characteristics.
Application Examples Substation Substation bus Riser pole SEL-FT50 Overhead conductor Underground feeder cable Breaker Wireless Relay SEL-FR12 Figure 11 Feeder Cable Egress Protection With Enhancements Implement a Low-Cost Fast Bus-Tripping Scheme A fast bus-tripping scheme uses a short-time delayed overcurrent element in the bus relay to provide a quick response to bus faults.
Application Examples 13 You can find further details in Low-Cost Fast Bus Tripping Scheme Using HighSpeed Wireless Protection Sensors (presented at WPRC, October 2018) and SEL application guide Using the SEL-FT50/SEL-FR12 System to Selectively Block Fuse-Saving and Accelerated Tripping in the SEL-351R Recloser Control (AG2018-14), both available at selinc.com.
Safety Information Safety Information Regulatory Information DANGER Install fault transmitters and sensors in accordance with normal safe operating procedures. These instructions are not intended to replace or supersede existing safety or operating requirements. Only trained qualified personnel with knowledge of high voltage safety should install or operate fault transmitters. CAUTION Although the power level is low, concentrated energy from a directional antenna may pose a health hazard.
Safety Information 15 Dangers, Warnings, and Cautions This manual uses three kinds of hazard statements, defined as follows: DANGER Indicates an imminently hazardous situation that, if not avoided, will result in death or serious injury. WARNING Indicates a potentially hazardous situation that, if not avoided, could result in death or serious injury. CAUTION Indicates a potentially hazardous situation that, if not avoided, may result in minor or moderate injury or equipment damage.
Network Deployment Overview WARNING AVERTISSEMENT Do not perform any procedures or adjustments that this instruction manual does not describe. Ne pas appliquer une procédure ou un ajustement qui n’est pas décrit explicitement dans ce manuel d’instruction. CAUTION ATTENTION Equipment components are sensitive to electrostatic discharge (ESD). Undetectable permanent damage can result if you do not use proper ESD procedures.
Network Deployment Overview 17 Research The first step in the deployment process is to identify possible installation sites for both the SEL-FR12 and SEL-FT50 devices, and then determine if a reliable link can be established. Short-Range Network A short-range network will have the SEL-FT50 devices deployed within a short distance of the SEL-FR12.
Network Deployment Overview An area study may also be performed for system with proposed repeaters. In this case, the characteristics of each segment must be considered. Use the SEL-RP50 receive sensitivity and EIRP values listed in Specifications.
Network Deployment Overview 19 If an alternative SEL-FT50 site is not available, consider whether the SEL-FR12 location could be moved to another point with better line of sight. Use the SEL-3031 as a backhaul device to carry the data back to the relay or recloser control that needs the fault information, as shown in Figure 16.
Device Installation SEL-FT50 Site Installation At the installation site, activate the SEL-FT50 by using a mini current loop. The mini current loop uses 120 Vac power so bring an inverter and extension cords to the SEL-FT50 installation site. Verify the RF connectivity by using a local SEL-FR12 (a different SEL-FR12, not installed in a cabinet) with an indoor antenna (SEL part number 235-0108). Verify that the local SEL-FR12 registers the local SEL-FT50 by examining the front-panel LEDs.
Device Installation 21 grounding and lightning protection devices. The antenna is typically mounted higher up on the pole in a safe location. The appropriate antenna type is sitespecific. Perform a path study before choosing the antenna. The SEL-FR12 serial port connects to one of the serial ports of the SEL-651R that are configured for SEL MIRRORED BITS communications. This connection allows the SEL-FR12 to share the received fault with the recloser control.
Device Installation Table 2 SEL-FR12 Orderable Antennas Type SEL Part Number Description Length Omnidirectional Diameter Mounting 90 mm (3.5 in) 37 mm (1.4 in) 915900494 235-0003 Low-profile 3 dBi Gain Omnidirectional Antenna, 698–960 MHz, 1710–2700 MHz, N Female Connector 235-0232 7.15 dBi Gain Omnidirectional Antenna, 902–928 MHz, N Female Connector 1358.9 mm (53.5 in) 235-0233 9.15 dBi Gain Omnidirectional Antenna, 902–928 MHz, N Female Connector 2476.5 mm (97.5 in) 33.3 mm (1.
Device Installation 23 Antenna System Ground Antenna system grounding is not included in the scope of this manual. Please consult a radio systems engineer or other professional for advice on ground-system design, and read SEL application guide Radio System Lightning Protection Best Practices (AG2014-36), which can be found on the SEL website. A welldesigned system will minimize equipment damage and risk of electric shock to personnel.
Device Installation Figure 18 Network ID Switch Selection Avoiding Radio Interference From Adjacent Networks The Network ID encoded in each message allows only SEL-FR12 Fault Receivers configured with the same Network ID to recognize that message. However, the broadcast radio frequency (channel) selection is controlled by the Unit ID setting in each SEL-FT50. The Network ID selection does not affect the radio channel.
Device Installation Figure 19 25 Serial Port Settings Selection Setting SEL-FR12 Receiver Gain The SEL-FR12 allows you to set the internal gain of the device. The device can be set to either Low Gain or High Gain for each trio of SEL-FT50 devices. The purpose of Low Gain mode is to ensure that you do not overdrive the receiver (which would decrease point link reliability).
Device Installation played if weak signals are arriving from distant devices. As each SEL-RP50 starts repeating the Link messages the RSSI reading might jump to a higher value. If you set the Gain switch to the High position based on these early readings, the signals from the closest SEL-RP50s might be too strong to be received. This is unlikely if the SEL-RP50s are installed according to the guidelines in Appendix D: SEL-RP50 Fault Repeater Detailed Implementation on page 54.
Device Installation 27 Table 6 RSSI Specifications for FR12-0004/FR12-0005 (Europe, Australia, and New Zealand) a Number of LINK LEDs Illuminated RSSI (High Gain Mode)a 0 –105 dBm or worse 1 –103 dBm 2 –101 dBm 3 –99 dBm 4 –97 dBm 5 –95 dBm 6 –93 dBm 7 –91 dBm 8 –89 dBm 9 –87 dBm 10 –85 dBm 11 –83 dBm 12 –81 dBm or better For RSSI values in Low Gain mode, add 16 dB to each value.
Device Installation SEL-451 Relay PROTO= MBA* SPEED = 38400 MBT = N TX_ID = 2 TX MODE = P STOPBIT = 2 RX_ID = 1 MBNUM = 8 * = MBA or MBB may be used SEL-2505/SEL-2506 Remote I/O Module SPEED = 38400 RX_ADD = 1 TX_ADD = 2 MIRRORED BITS Interface and Messages The SEL-FR12 communicates with a host device (protective relay or recloser control) through use of SEL MIRRORED BITS communications. The connection requires one serial port on the host device. The SEL-FR12 supports four port speeds: 9.6, 19.2, 38.
Device Installation Table 8 29 Definition of FAULT and LINK Bits Bit Label Definition LINK u u = Unit ID 1–12 SEL-FR12 is receiving messages from SEL-FT50 Fault Transmitters. Asserts whenever SEL-FR12 LINK LED u is solidly illuminated.
Device Installation Table 10 Detailed Command Set 3—SSEL-FR12 MIRRORED BITS Data Message Contents (Sheet 2 of 2) Required SEL-651R Transmit MIRRORED BITS (SELOGIC Equations) for Detailed Command Set (2) SEL-651R Received MIRRORED BITS (Relay Word bits) RMB1 RMB2 RMB3 RMB4 RMB5 RMB6 RMB7 RMB8 LINK 9 LINK 10 LINK 11 LINK 12 FAULT 11 FAULT 12 Response During Normal Conditions (No Fault on Trio 3 or Trio 4) Trio 3 FAULT = 0 Trio 4 FAULT = 0 LINK 7 LINK 8 Response During FAULT Indicatio
Device Installation 31 The SEL-FT50 only reads settings during startup; changing settings while the unit is turned on has no effect. Changing settings requires removal of device power. The SEL-FT50 retains some energy in storage and may take a couple of minutes to fully turn off. For an SEL-FT50 connected to an SEL-FR12, the device is fully turned off when the LINK LED for that unit starts blinking, indicating that the receiver has stopped receiving link messages from the SEL-FT50 transmitter.
Device Installation ➤ Use different Unit IDs for any SEL-FT50 trios that may experience simultaneous through-fault current, even if those SEL-FT50 Fault Transmitters are on different networks. See Avoiding Radio Interference From Adjacent Networks on page 24 for details. Setting the Network ID Configure your SEL-FT50 Fault Transmitters to communicate on the same network as your SEL-FR12 by giving both devices the same Network ID. Devices with different Network IDs cannot communicate.
Device Installation 33 Table 12 Fault Pickup Accuracy Considerations for FT50-0004/FT50-0007 (Europe and Mexico) Fault Pickup Level (rms) Host Relay Pickup Setting (rms) Load Behind FT50 (rms) 50 A > 75 A < 25 A 100 A > 130 A < 70 A 200 A > 260 A < 140 A 400 A > 480 A < 320 A 600 A > 720 A < 480 A 800 A > 960 A < 640 A 1000 A > 1200 A < 800 A 1200 A > 1440 A < 960 A This selection method guarantees that the SEL-FT50 picks up for any fault that the protective device element can s
Device Installation Repeater ID SW1-SW3 1 2 3 4 5 N/A N/ALegacy *SW4-SW8 are unused Figure 22 SEL-RP50 Switch Selections Labels Setting the Unit ID When configuring one or more SEL-RP50 Fault Repeaters to forward wireless messages from a single SEL-FT50, the Unit ID settings must match. In a typical three-phase SEL-FT50 installation, the Unit IDs are selected from one of four Trios, as shown in Table 4.
Device Installation NOTE: Each SEL-RP50 repeater ID adds approximately 1 ms latency to the fault response at the SEL-FR12 35 If only one repeater site is installed for a Trio, any repeater ID can be used. A smaller value provides the lowest latency, so using repeater ID = 1 keeps it simple. A special Repeater ID = Legacy is provided when using SEL-FT50s manufactured before May 2021. These older SEL-FT50s are not compatible with the numeric Repeater ID selections, and only one repeater site can be used.
Device Installation Figure 24 SEL-FT50/SEL-RP50 Installation Position Step 3. Apply slight upward pressure until the device is secured around the line as shown in Figure 25. Figure 25 SEL-FT50/SEL-RP50 Secure on the Line Step 4. Use the shotgun stick to adjust the transmitter orientation so that it is directly vertical. This is important to ensure the best propagation characteristics for the internal antenna.
Dimensions 37 Dimensions SEL-FT50 TOP 5.58 [141.7] 4.49 [114.2] FRONT RIGHT REAR 6.97 [177.0] BOTTOM LEGEND in [mm] i9373a Figure 26 SEL-FT50 Dimensions for FT50-0001/FT50-0003/FT50-0005/ FT50-0006 (U.S.A.
Dimensions i9358a Figure 27 Mexico) SEL-FT50/SEL-FR12 Fault Transmitter and Receiver System SEL-FT50 Dimensions for FT50-0004/FT50-0007 (Europe and Instruction Manual Date Code 20210405
Dimensions 39 SEL-FT50 TOP 5.58 [141.7] 4.49 [114.2] FRONT RIGHT REAR 6.97 [177.0] BOTTOM LEGEND in [mm] i9373a Figure 28 SEL-RP50 Dimensions for RP50-0001 (U.S.A.
Dimensions Figure 29 SEL-FT50/SEL-FR12 Fault Transmitter and Receiver System SEL-FR12 Dimensions Instruction Manual Date Code 20210405
Specifications 41 Specifications Overvoltage Compliance Category III (SEL-FT50 and SEL-FR12) Designed and manufactured under an ISO 9001 certified quality management system Insulation Class CE Mark SEL-FT50, SEL-RP50: Class III RoHS compliant SEL-FR12: Class I General System Operating Temperature Power System Frequency Range –40° to +85°C (–40° to +185°F) 45–65 Hz Storage Temperature Current Pickup Level (rms) –40° to +85°C (–40° to +185°F) Note: Units are individually configurable.
Specifications Type Tests SEL-RP50 Minimum current Fully Awake: load current > 40 A Semi-Awake: load current > 5 A Electromagnetic Compatibility Emissions Radiated: 47 CFR Part 15.109 Class A Conducted: 47 CFR Part 15.107 Class A SEL-FR12 Power Requirements Rated Voltage: 12–24 Vdc Operational Voltage: 9–30 Vdc Power Consumption: <2 W Electromagnetic Compatibility Immunity Radio System Electrostatic Discharge: IEC 61000-4-2:2008 IEEE C37.90.
Specifications Table 13 Certifications by Country Country Part Number Authority U.S.A.
Appendix A: Manual Versions Appendix A: Manual Versions Instruction Manual The date code at the bottom of each page of this manual reflects the creation or revision date. Table 15 lists the instruction manual versions and revision descriptions. The most recent instruction manual version is listed first. Table 15 Instruction Manual Revision History (Sheet 1 of 2) Date Code Summary of Revisions 20210501 Globally ➤ Added new product SEL-RP50 Fault Repeater.
Appendix A: Manual Versions Table 15 45 Instruction Manual Revision History (Sheet 2 of 2) Date Code Summary of Revisions 20180613 ➤ ➤ ➤ ➤ ➤ ➤ Added Network Deployment Overview. Updated Table 2: SEL-FR12 Orderable Antennas. Added Commissioning the SEL-FR12 heading. Updated Table 12: Fresnel Zone Radius (900 MHz). Updated Specifications. Added Appendix C: Link Budget Analysis. 20180308 ➤ ➤ ➤ ➤ Updated Table 2: SEL-FR12 Orderable Antennas.
Appendix B: Two-Branch Application Appendix B: Two-Branch Application This application has two three-phase branches, A and B, as shown in Figure 30. Branch B has a fuse and uses a fuse-blowing scheme, while Branch A does not. When a fault occurs on Branch A, the recloser operates to clear the fault.
Appendix B: Two-Branch Application Table 17 Settings for the SEL-FR12 Network ID BAUD RX_ADD TX_ADD Trio 1 Gain Trio 2 Gain Trio 3 Gain Trio 4 Gain 3—(0010) 38400 1 2 High Gain High Gain High Gain High Gain Table 18 SEL-651R Settings PROTO SPEED TXID RXID MB8A or MB8B 38400 1 2 Table 19 47 SEL-651R Transmit MIRRORED BITS Settings TMB1A TMB2A TMB3A TMB4A TMB5A TMB6A TMB7A TMB8A Comments 0 0 0 0 0 0 0 TRGTR The TARGET RESET pushbutton of the SEL-651R resets the
Appendix C: Link Budget Analysis Appendix C: Link Budget Analysis Overview A radio link budget accounts for all losses and gains in a radio link from the transmitter to the receiver. Link budget calculations are used to determine the amount of link margin available for a given radio link. The link budget includes five components: radio transmit power, antenna gains, cable and path losses, interference margin, and radio receiver sensitivity.
Appendix C: Link Budget Analysis 49 The SEL-FR12 must be connected to an external antenna, but because the SEL-FR12 is not a transmitter, you may attach any size antenna to the device. Keep in mind that larger antennas will amplify the desired signal, but also interference in the band. Path Loss Path loss is attenuation of the transmitted signal as it propagates between the transmitter and the receiver.
Appendix C: Link Budget Analysis radius of 4.96 m (16.27 ft). For a distance of 16 km (10 mi) between antennas, the Fresnel zone radius is 36.21 m (118.8 ft). Table 21 provides the Fresnel zone radius for some typical path distances. d1 d2 d b Figure 32 Fresnel Zone d b = 547.
Appendix C: Link Budget Analysis 51 Antenna Polarization Loss While hanging on the line, the SEL-FT50 has a vertically polarized antenna. The SEL-FR12 should use a vertically polarized antenna to match. Antenna polarization refers to the orientation of the e-field in the radiated RF signal. The omnidirectional antennas listed in Table 20 are all vertically polarized. The Yagi antennas are polarized in the direction of the short radiating elements of the antenna (either vertically or horizontally).
Appendix C: Link Budget Analysis RX Signal Strength (dBm) = TX Power (dBm) – Line Loss FLR (dBi) – Attenuation FLR (dB) + Antenna Gain FLR (dBi) – Path Loss (dB) + Antenna Gain FLT (dBi) – Line Loss FLT Equation 5 Effective RX Sensitivity (dBm) = RX Sensitivity (dBm) – Interference Margin (dBm) Equation 6 Link Margin (dB) = RX Signal Strength (dBm) – Effective RX Sensitivity (dBm) Equation 7 Link Budget Calculation Example The SEL-FR12 antenna is mounted half-way up a utility pole and the SEL-FT50 is
Appendix C: Link Budget Analysis 53 Effective Receive Sensitivity (Equation D.6) Effective RX Sensitivity (dBm) = –97 (dBm) – (–6 (dB)) Effective RX Sensitivity (dBm) = –91 (dBm) Link Margin (Equation D.7) Link Margin (dB) = –84.3 (dBm) + 91 (dBm) Link Margin (dB) = 6.7 (dB) A link margin of 6.7 dB is likely to provide insufficient coverage for this application. Consider increasing the SEL-FR12 antenna gain, and changing the location of the SEL-FT50 to avoid obstructions.
Appendix D: SEL-RP50 Fault Repeater Detailed Implementation Appendix D: SEL-RP50 Fault Repeater Detailed Implementation The SEL-RP50 Fault repeater provides a method to help break the line-of-sight restrictions for SEL-FT50 to SEL-FR12 wireless communications paths. This appendix provides details on where SEL-RP50s can help, and where they might not. Example system example diagrams explain configuration details.
Appendix D: SEL-RP50 Fault Repeater Detailed Implementation ➤ When the SEL-RP50 is in sleep mode (see below) a single SEL-RP50 needs up to 30 minutes to synchronize to the link messages coming from the SEL-FT50. If more than one SEL-RP50 is present (with the same Unit ID) the link message synchronization period repeats for each SEL-RP50. ➤ The SEL-FT50 and SEL-RP50 are non-directional devices. They operate the same for load or fault current flowing in either direction.
Appendix D: SEL-RP50 Fault Repeater Detailed Implementation ➤ Trio 2 uses two SEL-RP50 sites to reach the SEL-FR12 because of a forested area ➤ Trio 3 uses one SEL-RP50 site to reach the SEL-FR12 because of a forested area ➤ Trio 4 uses one SEL-RP50 site to reach the SEL-FR12 because of a mountain Figure 35 Energy Harvesting and SEL-RP50 Power States The SEL-RP50 harvests energy from line current, just like the SEL-FT50.
Technical Support 57 Link Message repeating: ➤ When a feeder is powered up to a low load condition, the SEL-RP50 wireless repeaters are in a sleep state and do not continually operate. In this state they periodically turn on the radio to listen for Link signals, and then go back to sleep to save energy. The system is designed to eventually capture an incoming Link message and then synchronize the wake up timer.
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