中文品名：ABB O3ES 励磁测量信号调理模块

Order No: O3ES，物料号 HENF445789R1

The O3ES HENF445789R1 is Eurocard‑format plug‑in analog measuring‑conditioning board for ABB UNITROL legacy static excitation system. It is dedicated for generator voltage and current transformer secondary signal filtering, isolation and amplitude conversion. It converts high‑level AC measuring signals into low‑level standard signals for excitation main‑processor sampling. This is discontinued legacy hardware, widely used for spare‑part replacement of old thermal‑power and hydro‑power generating‑unit excitation cabinets。Not hot‑swappable.

‑ Power Supply：Supplied by rack back‑plane 24 VDC；typical power consumption 7.2 W

‑ Mechanical Structure：standard Eurocard plug‑in board, front‑panel locking handle；weight approx 0.83 kg

‑ On‑board Resources：multi‑channel AC signal filtering circuit, isolation transformer components, amplitude‑adjustment circuit, surge‑suppression components, conformal‑coating protection

‑ Communication Interface：field measuring‑transformer signal input terminals；back‑plane analog signal output interface to main‑processor / I/O board

‑ Galvanic Isolation：galvanic isolation between PT/CT secondary field‑signal side and excitation internal logic side, isolation rating 2500 VAC

‑ Core Function：generator terminal voltage, stator current AC signal filtering, isolation transformation, amplitude conditioning for sampling circuit

‑ Protection：input‑channel surge‑suppression, over‑voltage limiting protection for measuring‑loop

‑ Status LED Indicators：power‑supply indicator LED

‑ Weight：approx 0.83 kg

‑ Receives AC secondary signals from generator voltage transformer and current transformer, completes filtering and noise suppression, eliminates field‑site electromagnetic interference.

‑ Through built‑in isolation transformers, accomplishes electrical isolation between high‑potential measuring loop and low‑voltage excitation control circuit, prevents high‑voltage surge from damaging subsequent control boards.

‑ Adjusts signal amplitude, converts raw PT/CT secondary signals into standardized low‑level analog signals, transmits to O3EEb main‑processor or O3EC I/O module for calculation of AVR regulation and protection logic.

‑ Pure analog signal‑conditioning hardware without independent CPU; conformal‑coating circuit board improves anti‑humidity and anti‑dust performance for cabinet environment.

‑ Cannot run independently; must cooperate with UNITROL excitation rack, voltage/current transformers and main‑processor module. O3ES HENF445789R1 belongs to dedicated excitation measuring‑board, cannot be substituted by general‑purpose DCS analog‑input modules.

‑ No self‑diagnosis CPU. Channel fault is reflected by measuring‑value deviation on excitation system.

‑ No local historical‑data storage; signal‑abnormality information is observed via excitation commissioning tool.

‑ Module damage, component aging or channel abnormality will cause voltage / current sampling deviation; serious fault will lead to AVR regulation disorder and excitation‑protection mis‑operation.

‑ Front‑side screw terminals: connect to PT / CT secondary measuring‑signal cables.

‑ Back‑plane connector: inserts into UNITROL rack slot, outputs conditioned analog measuring signals to excitation internal boards.

‑ Mounting：insert into UNITROL excitation cabinet standard Eurocard rack slot

‑ Operating Temperature：‑10 ℃ ~ +60 ℃

‑ Storage Temperature：‑40 ℃ ~ +70 ℃

‑ Relative Humidity：5‑95 %RH, non‑condensing

‑ Protection Class：IP20, cabinet‑internal installation.

‑ Cut off measuring‑loop secondary circuit and cabinet auxiliary power before inserting or replacing this module. Strictly follow wiring requirements for PT/CT secondary circuit, prohibit open‑circuit for CT secondary loop.

‑ For spare‑part replacement: verify full model O3ES and part‑number HENF445789R1; after replacement check signal‑wiring, verify generator voltage and current sampling accuracy through commissioning tool. Hardware‑version mismatch will result in measuring‑signal scaling error risk.

‑ Module fault will cause excitation‑system generator voltage / current measuring‑channel failure.

Thermal‑power and hydro‑power generator static excitation cabinets; ABB UNITROL‑series old excitation‑system maintenance and spare‑part replacement; industrial spare‑part for excitation‑system PT/CT signal isolation‑conditioning unit.