A5E3O947477 Siemens A5E30947477 POWER SUPPLY

Siemens A5E30947477 | SIMATIC PC Industrial Power Supply — 24V DC / 150W / Rev. H3 / IPC627B-C / IPC827B-C / HMI IPC677B-C / HMI IPC577B-C 

The Internal Power Supply That Keeps SIMATIC IPCs Running

The A5E30947477 is the internal DC power supply for Siemens' SIMATIC IPC (Industrial PC) and HMI IPC product families — specifically the B and C model variants of the IPC627, IPC827, IPC677, and IPC577 systems. Unlike standard AC-input PC power supplies, this is a 24V DC input industrial power supply: it takes 24V DC from the control cabinet power distribution and converts it to the regulated voltages the IPC's motherboard and components require.

The 24V DC input design is intentional for industrial automation use. SIMATIC IPCs installed in machine control cabinets run from the cabinet's 24V DC bus rather than from an independent mains AC connection, simplifying panel design and giving the IPC protection through the cabinet's 24V DC power management, including controlled shutdown behaviour when cabinet power is cut.

At 150W, the A5E30947477 covers the power budget of the IPC627B/C and IPC827B/C industrial PC platforms and the HMI IPC677B/C and IPC577B/C operator station platforms. If the internal power supply fails, the SIMATIC IPC shuts down entirely — the host CNC, PLC, or SCADA system loses its HMI or industrial PC function until the power supply is replaced.

Key Specifications

No Replacement — Sourcing from the Aftermarket

Radwell and other authorised spare parts distributors list "NO REPLACEMENT" for the A5E30947477. Siemens does not offer a direct substitute spare part for this unit. For the IPC627B/C, IPC827B/C, IPC677B/C, and IPC577B/C systems still in service, the only path to replacing a failed power supply is the SIMATIC IPC aftermarket — tested used or new old stock (NOS) A5E30947477 units from spare parts dealers.

FAQ

Q1: What causes the A5E30947477 power supply to fail?

Industrial power supplies in continuously operating systems fail primarily through electrolytic capacitor degradation over time — capacitors dry out, lose capacitance, and increase ESR, causing output voltage ripple and eventual regulation failure. Secondary failure modes include inrush protection components, over-voltage protection circuits, and fan failure (if the unit has a cooling fan). A SIMATIC IPC that fails to power on, powers on intermittently, or crashes unexpectedly without OS-level cause often has a failing internal power supply.

Q2: Can a standard ATX PC power supply substitute for the A5E30947477?

No. Standard ATX power supplies accept 100–240V AC mains input. The A5E30947477 requires 24V DC input. The physical form factor and connector pinout also differ from ATX standards. Only a 24V DC input power supply with the correct physical dimensions and connector configuration for the CV5/4 chassis variants can substitute.

Q3: How is a power supply failure confirmed before ordering a replacement?

Measure the 24V DC input at the power supply's input connector — confirm it is present and within the 24V DC specification. If input power is confirmed and the IPC still does not respond to power-on, the internal power supply is the likely fault. A Siemens-qualified technician can measure the power supply's DC output rails directly, but this requires safe access inside the IPC chassis.

Q4: Is the A5E30947477 repairable?

Repair is possible through experienced industrial PC power supply repair services. Capacitor replacement on a degraded but not fully failed unit is a common and cost-effective repair when new old stock is unavailable. A repair centre with SIMATIC IPC test capability can verify the repaired unit before return.

Q5: Where is the A5E30947477 sourced?

Through the Siemens SIMATIC IPC spare parts aftermarket — Siemens-authorised service centres (while stock exists), industrial PC parts dealers, and tested surplus suppliers. Because no direct replacement is available, confirm the A5E30947477 specifically from the installed unit's label. Demand for this unit in the B/C model IPC aftermarket means stock availability varies.