A06B-6115-H003 Fanuc Power Supply Module A06B6115H003 AO6B-6II5-HOO3

FANUC A06B-6115-H003 | Alpha i PSMR-3i Regenerative Power Supply Module — 200–240V AC / 3.8kW DC Bus / 3-Phase

PSMR — Regenerative Power Supply for the Alpha i Drive System

The A06B-6115-H003 is the PSMR-3i (Power Supply Module, Regenerative, 3kW class) in FANUC's Alpha i drive series. It is the AC-to-DC conversion stage for the entire drive system — taking three-phase 200–240V AC mains and converting it to a 283–339V DC bus that the servo amplifier (SVM) and spindle amplifier (SPM) modules connected to the same DC bus draw from.

The "R" in PSMR identifies this as a regenerative power supply. During motor deceleration, the servo and spindle amplifiers return braking energy back along the DC bus to the PSMR module, which converts it to AC and feeds it back into the mains supply. This regenerative operation reduces heat dissipation in the drive system compared to non-regenerative supplies that dissipate braking energy as heat through resistors. It also reduces energy consumption on machines with frequent deceleration cycles.

At 3.8kW rated output, the A06B-6115-H003 / PSMR-3i serves smaller drive configurations — single or dual-axis machines where the total continuous power demand of the connected SVM and SPM modules falls within this rating. Larger drive systems with higher total power demand require PSMR modules from higher-rated variants in the A06B-6115 or A06B-6121 families.

Key Specifications

Alarm Codes — What Each Alarm Means

The PSMR-3i front LED display shows alarm codes at fault:

Reading the alarm code at the time of failure is the essential first diagnostic step — each code identifies the specific fault circuit and guides the repair.

FAQ

Q1: What is the difference between a PSM and a PSMR module?

PSM (Power Supply Module) provides AC-to-DC conversion without regeneration — braking energy is dissipated as heat through external resistors. PSMR (regenerative) returns braking energy to the AC mains. PSMR modules reduce heat dissipation and energy consumption on machines with frequent braking cycles. The PSMR-3i (A06B-6115-H003) is the regenerative type. PSM and PSMR modules are not interchangeable — system configuration must specify which type is used.

Q2: AL-2 appears on the PSMR-3i. What is the correct action?

AL-2 indicates the internal cooling fan (A90L-0001-0441) has stopped. Power down the system immediately — operating without cooling fan causes thermal damage to the power module within minutes. Replace the fan (A90L-0001-0441) and confirm fan operation at next power-on. Check the fan connector and wiring before replacing the fan, as a loose connector is a common cause.

Q3: The PSMR-3i shows AL-5 (capacitor not recharged). What causes this?

AL-5 occurs when the DC bus capacitors do not charge to the expected voltage within the specified time after power-on. Common causes: one phase of the AC input supply is missing or low voltage; internal precharge circuit fault; capacitor degradation (very old units). Check all three phases of the incoming AC supply first. If three-phase power is confirmed good, internal service is required.

Q4: Can the A06B-6115-H003 be repaired, or must it be replaced?

Repair is available and cost-effective for PSMR modules. Common failure points include the rectifier diodes, IGBT transistors in the regenerative inverter section, gate driver circuits, capacitor bank degradation, and the cooling fan. Specialist FANUC drive repair centres with Alpha i PSMR test equipment can diagnose and repair the module under load conditions to confirm full regenerative function before return.

Q5: What is the power rating rule for matching PSMR-3i to servo and spindle modules?

The total rated continuous power of all SVM and SPM modules connected to the DC bus must not exceed the PSMR's rated output (3.8kW for the PSMR-3i). For transient peak power during acceleration, FANUC's drive system design guidelines specify a derating factor. If the connected amplifiers' combined power demand exceeds the PSMR rating, the module trips on AL-1 (overcurrent) or AL-7 (DC voltage high) under load. Upgrading to a higher-rated PSMR resolves the undersizing.