lee@ricewind.comTel+86 17621197907Serving 50+ countries
RICEWIND

Huawei / DC power systems

R4850N1 Equipment information & support

The Huawei R4850N1 is a reliable AC/DC switch-mode power module featuring active PFC and soft-switching topology to provide filtered -48V DC power with automated load balancing.

Equipment information

Brand
Huawei
Equipment model
R4850N1
Equipment type
DC power systems
Controller / software version
Confirm against the installed equipment
View full product specifications
R4850N1 Official Product View 1

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

Nominal DC Output Voltage
-48 V DC
Rated Output Current
50 A
Power Conversion Efficiency
94.0 %
Physical Dimensions Spec
130 × 85 × 285 mm
AC Input Voltage Range
85 ~ 300 V AC
Operating Temperature
-40 ~ +75 °C

Alarms & troubleshooting

AC_IN_FAIL (AC Input Failure)
Green Power LED off, Yellow Alarm LED solid on (all off during blackout)
Mains blackout, AC input voltage outside operating range (85V-300V AC), or upstream AC breaker tripped.
1. Measure AC voltage across L/N on the slot backplane using a multimeter; 2. Verify that the upstream AC branch breaker is closed; 3. If AC input is within 85V-300V but the unit does not recover, reseat the rectifier; replace if fault persists.
OUT_OVP (DC Output Overvoltage Lockout)
Red Fault LED solid on, Green Power LED off
Internal voltage regulation loop failure causing output voltage to exceed the hardware protection threshold (>59.5V DC), triggering hardware lockout.
1. Disconnect AC power by flipping the module breaker and remove the unit for 3 minutes; 2. Reseat the module and power on to attempt a manual reset; 3. Monitor the module voltage reporting on the host SMU; 4. If the unit trips into OVP again, replace the rectifier immediately.
OVER_TEMP (Rectifier Over-Temperature Protection)
Yellow Alarm LED solid on during derating; Red Fault LED solid on and Green LED off during thermal shutdown
Ambient temperature exceeds operating limit (>65°C), dust filter/air inlet grill clogged, or airflow circulation blocked.
1. Check room air conditioning to restore ambient temperature to -40°C to +65°C; 2. Clean dust and debris from the front air inlet mesh and cabinet dust filters; 3. Ensure rear cabinet exhaust is unobstructed; verify that the unit automatically recovers once temperature drops below 55°C.
FAN_FAIL (Rectifier Fan Fault/Locked)
Red Fault LED solid on, Green Power LED blinking slowly or solid on
Fan bearing wear/failure, foreign object mechanically jamming the blades, loss of tachometer signal, or drive circuit defect.
1. Visually inspect the front fan blades for foreign objects or physical blockage; 2. Blow out accumulated dust with dry compressed air; 3. Reseat the module; if the fan fails to spin up or the tachometer alarm persists, replace the fan assembly or the entire rectifier module.
COMM_FAIL (CAN Communication Loss & Current Sharing Imbalance)
Yellow Alarm LED blinking at 0.5 Hz, Green Power LED solid on
Loose CAN-bus connector pin contact, monitoring controller (SMU) port malfunction, backplane bus open-circuit, or damaged internal CAN transceiver IC causing active current share loss.
1. Check SMU operational status and confirm CAN terminating resistance is intact; 2. Withdraw the rectifier module and inspect gold fingers for bent pins, corrosion, or contamination; 3. Insert the module into a known-good slot; if yellow LED continues blinking at 0.5 Hz, replace the rectifier module.

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

Share on-site information

  1. 01

    Identify the exact model

    Record the nameplate, system model and controller or module model.

  2. 02

    Keep the alarm details

    Record the full alarm text, indicator colour, timing and whether it persists.

  3. 03

    Describe recent changes

    Note recent replacements, software updates or configuration changes.

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.

Your model and these details will be added to the enquiry form for you to review before sending.

Related technical articles

Browse the technical guides or send a question about this model.

View all articles

Need a replacement module or supporting equipment?

Confirm the full model, system configuration and compatibility requirements before enquiring about suitable products.

Ask about suitable products

Have a model and an on-site issue?

Share the exact model, alarm text and observed symptoms to help identify relevant information and compatibility requirements.

Request technical support