Product Core Brief

• Model: UBC717BE101 Z , OEM part number 3BHB006714R0277
• Brand: ABB
• Series: SYNCHROTACT 5 dual-channel generator synchronizer & synchrocheck protection relay
• Core Function: Simultaneously evaluates two independent generator/grid PT signal pairs to enable safe, out-of-phase-free breaker paralleling on dual busbar power station layouts
• Product Type: Panel cutout mounted dual-channel galvanically isolated synchronizing protection device
• Key Specs: Dual isolated PT measuring loops | SIL2 / Cat.3 PL d certified | Dual 10/100BASE-T Ethernet ports
• Note: Full platform end-of-life; factory sealed new assemblies and fully cyclic load-tested surplus available for combined-cycle, hydro and cogeneration plant cabinet maintenance

Key Technical Specifications

• Per-channel PT input range: 50–130 VAC single-phase, channel-to-channel isolation 1500 VAC
• Configurable synchronization thresholds: Voltage difference 0.1–40%, slip frequency 0.01–6%, phase angle 1–99°
• Breaker close command latency: Fixed 10 ms core response, pulse width adjustable 50–990 ms
• Communication interfaces: Dual redundant 10/100 Mbps Ethernet, secondary RS485 Modbus RTU
• Auxiliary operating supply: 24 VDC ±10% SELV, max 20 W power draw
• Safety compliance: IEC 61508 SIL 2, IEC 60255-127 synchrocheck standard, CE certified
• Local HMI: Backlit monochrome LCD, dedicated RUN, CH1 FAULT, CH2 FAULT LED array for each measuring loop
• PCB coating: ISA S71.04 G3 conformal coating standard for coastal high-humidity corrosive cabinet environments
• Standard panel cutout: Unified SYNCHROTACT 5 horizontal mounting footprint
• Operating ambient temperature: -10°C to +60°C sealed cabinet; storage -40°C to +85°C
• Humidity tolerance: ≤75% RH non-condensing below 55°C
• Net unit weight: 0.78 kg

Product Introduction

This panel-mounted relay runs two fully independent synchronization calculation cores, with hardware isolation that prevents a fault on one PT measurement loop from disrupting paralleling operations on the second circuit. Its dual redundant Ethernet ports eliminate single-point communication failure for remote SynView configuration and disturbance waveform logging, and the internal cross-monitoring logic blocks breaker closing if phase angle, voltage or slip values exceed configured safe window limits.

QA & Testing SOP

1. Incoming Inspection: Cross-reference serial number against ABB power protection spare asset database to filter counterfeit assemblies; inspect dual ST fiber/RJ45 ports, rear PT terminal blocks and front LCD display with a 10x magnifier for ferrule scratches or thermal pin corrosion; log serial numbers for full generator SIS traceability records.
2. Live Testing: Mount the unit on a standard panel test bench paired with four independent variable AC signal sources simulating two generator and two grid PT feeds; supply rated 24VDC auxiliary power; run a continuous 24-hour cycle test including slip deviation sweeps, phase angle window validation and primary Ethernet cable pull to confirm automatic secondary port failover.
3. Electrical Testing: Use a Fluke 115 insulation tester to verify ≥10MΩ isolation between PT high-potential measuring circuits and cabinet chassis ground; measure PE continuity resistance below 0.5Ω.
4. Firmware/Config Backup: Photograph front LED fault mapping and Ethernet IP DIP switch positions; record exact firmware revision printed on internal PCB silkscreen to match site existing synchronizer logic versions.
5. Final QC & Packaging: Wipe front LCD surface with static-dissipative microfiber cloth; cap Ethernet and PT terminal ports with insulating dust covers; seal the unit inside a shielding ESD bag, attach a printed QC tag with full 24-hour dual-channel paralleling cycle test timestamp, then pack into foam lined transit cartons.

Installation Pitfalls & Guide

❗ Firmware revision mismatch breaks dual-channel cross-check logic: Older firmware builds lack redundant loop fault suppression algorithms; match the exact firmware version of the site’s existing hardware before power-on to avoid constant false synchrocheck fault alarms. ❗ PT polarity reversal creates permanent 180° phase offset on individual channels: Swapped secondary PT wiring locks the affected loop out of all paralleling window calculations until polarity correction and full power cycle. ❗ Unshielded twisted pair Ethernet cabling generates constant TCP retries: Cable runs longer than 12 m near variable frequency drives and MCC motor starters induce periodic signal transients that drop event log data packets. ❗ ESD discharge destroys internal ADC sampling ICs: Bare finger contact with PCB measuring traces disables one or both PT input loops, requiring full unit replacement and multi-day generator production outage windows. ❗ Hot-swap energized PT secondary circuits creates lethal open-circuit surge voltage: Removing the unit under live cabinet power disrupts the shared protection bus and creates unmonitored generator operation blind zones that violate SIL2 safety compliance rules.

4-step replacement guide

1. Pre-install: Lock out and tag cabinet 24VDC auxiliary power supply breaker; short all PT secondary test switches via test switch hardware; wait 10 minutes for internal logic capacitors to fully discharge; don ESD wrist strap; capture photos of dual PT wiring, dual Ethernet cabling and Ethernet IP DIP switch layout.
2. Removal: Disconnect all PT measuring wires and dual Ethernet communication cables channel by channel; release four panel mounting fasteners, pull the old unit straight out of the cabinet cutout without twisting rear wiring harness pins.
3. Install: Set DIP switches on the new hardware to match photographed IP address values; seat the unit flush against the cabinet panel to maintain IP20 internal enclosure rating; re-terminate all dual PT and Ethernet wiring following captured photos, double-check each PT loop polarity sequence.
4. Power-on Test: Restore cabinet 24VDC auxiliary power; confirm steady green RUN LED and active LCD readout for both measurement channels; inject calibrated generator/grid PT signals to validate independent voltage/frequency trimming logic; simulate primary Ethernet cable pull to confirm automatic secondary port communication failover with zero paralleling command interruptions.

FAQ

Q: Can this hardware operate with only one PT input channel connected? A: It will execute synchronization logic on the single active loop, but dual-channel cross-wiring fault detection is fully disabled. This removes a critical SIL2 safety monitoring layer and violates plant SIS operational compliance documentation for dual-busbar power station layouts. Q: Is hot-swapping supported while cabinet 24VDC auxiliary power and PT circuits remain energized? A: It is not supported. Live extraction creates lethal open-circuit PT secondary voltage transients and disrupts the cabinet’s shared differential protection bus, leaving generator operation unmonitored during the replacement window. Full power lockout and PT shorting via test switches are mandatory before disassembly. Q: What warranty coverage applies to stocked units? A: Factory-new original dual-channel synchronizers carry a 12-month OEM warranty covering dual PT ADC measurement circuits, redundant Ethernet transceivers, breaker close relay assemblies and front diagnostic LED arrays. Load-tested surplus units come with a 6-month functional warranty. Damage from contaminated PT wiring, ungrounded ESD handling or energized hot-swap removal voids all SIL2 certification and warranty validity. Q: What hardware replaces this unit for new power station builds? A: New SYNCHROTACT 5 deployments use SYN5202-0273 with expanded fault waveform recording and enhanced slip detection algorithms. This variant remains approved only for one-to-one maintenance replacement of pre-2024 installed dual-channel synchronizing relays. Q: Will stored synchronization threshold settings be lost after a full cabinet power outage? A: All voltage, slip and phase angle window parameter sets save to on-board non-volatile Flash memory, so power loss does not erase site-specific tuning values. Only physical DIP switch Ethernet IP address configurations require manual matching after hardware swap. Q: What are the most common failure modes for a faulty unit? A: Persistent red FAULT LED on one or both channels with correct PT wiring, failure to send valid breaker close trim signals to turbine/excitation control hardware, loss of automatic redundant Ethernet port failover, severe measurement drift between the two isolated PT loops, blank LCD backlight with normal 24VDC auxiliary supply, and inability to log dual-channel paralleling fault events to remote SCADA servers.