Huawei / SFP / SFP+ Optical Transceivers

100G-4*25-850NM-100M-MM-QSFP28 Equipment information & support

Huawei 100G-4*25-850NM-100M-MM-QSFP28 is an industrial-grade, high-reliability solution engineered for mission-critical telecom sites, data centers, and power applications.

Equipment information

Brand: Huawei
Equipment model: 100G-4*25-850NM-100M-MM-QSFP28
Equipment type: SFP / SFP+ Optical Transceivers
Controller / software version: Confirm against the installed equipment

View full product specifications

Huawei 100G-4*25-850NM-100M-MM-QSFP28 pure white studio product shot

Information below comes from the current product catalogue. Confirm the controller, software version and configuration of the installed equipment separately.

Form Factor: Hot-pluggable QSFP28 / SFP+ Optical Footprint
Optical Connector Type: Duplex LC / MPO Optical Connector Interface
Laser Type: High Stability DFB Laser / VCSEL Array & PIN Detector
Power Dissipation: Ultra-low Power Consumption (< 1.5W ~ 3.5W)
Digital Diagnostic Monitoring (DDM): Real-time DOM / DDM Optical Monitoring
Operating Case Temperature: -0 ~ 70°C

Alarms & troubleshooting

AC_FAIL (AC Mains Input Failure/Out of Range)

RUN LED (Green) OFF; ALM LED (Yellow) or FAULT LED (Red) Solid ON

Utility blackout, branch breaker trip, AC phase voltage below 80VAC or above 300VAC cutoff, or loose chassis rear connector pin

1. Measure AC input terminal voltage to verify it within normal envelope; 2. Check and reset the branch miniature circuit breaker (MCB); 3. Unseat and inspect rear connector pins, then reseat firmly; 4. If AC supply is stable and reseating fails, replace module.

DC_VOLT_HIGH (DC Output Overvoltage Hardware Lockout)

FAULT LED (Red) Solid ON, module output completely gated and locked off

Internal optocoupler feedback loop failure, strong EMI on current-share bus, or hardware overvoltage comparator trip (>59.5VDC)

1. Disconnect AC input, wait 2 minutes for capacitor discharge, then re-energize; 2. If overvoltage trips immediately, internal regulation circuit is defective—replace module; 3. Verify float/boost voltage calibration in the central controller.

FAN_FAIL / OVER_TEMP (Cooling Fan Stall or Internal Thermal Runaway)

ALM LED (Yellow) Blinking continuously; cooling fan halted or abnormal acoustic noise

Airflow channel heavily clogged by dust/debris, seized fan bearing, ambient temperature exceeding +55°C, or disconnected fan tachometer signal cable

1. Extract module and clean air filters and heatsink fins; 2. Manually spin fan blades to ensure smooth rotation without friction; 3. Verify room air conditioning system; 4. If fan remains halted after cleaning, replace fan assembly or unit.

COMM_LOST (Telemetry / CAN Bus Communication Loss)

Controller screen displays 'Module Lost/Offline', module operates in autonomous fallback float mode

Oxidized gold fingers on backplane interface, improper CAN termination resistor, duplicated node ID address, or controller lockup

1. Remove module and clean rear gold-finger contacts with isopropyl alcohol; 2. Run 'Rescan Nodes' on controller GUI; 3. Verify the 120-ohm CAN termination jumper; 4. Soft reboot the central supervision unit.

SHORT_CIRCUIT / I_LIMIT (DC Short Circuit or Current Foldback Limit)

ALM LED (Yellow) Solid ON, output voltage clamped down below safety foldback threshold

Downstream DC branch cabling short-circuit, internal battery cell short, or severe inrush load current exceeding 120% rating

1. Sequentially switch off downstream DC distribution breakers to pinpoint faulted branch; 2. Disconnect battery breaker to test open-circuit terminal voltage; 3. Once external short is isolated, module recovers regulated output automatically.

Access Complete Maintenance & Full Alarm Troubleshooting Manual

This page lists high-frequency critical alarm codes commonly encountered in field maintenance. Comprehensive manufacturer troubleshooting matrices, board-level repair guides, detailed electrical schematics, and firmware commissioning manuals are delivered alongside equipment upon formal project procurement, accompanied by dedicated FAE technical support.

Contact Account Manager for Full Manual

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Record information visible in the existing interface. Electrical measurements, disassembly and replacement should follow the applicable manufacturer's manual and be performed by qualified personnel.