Description
1. Unboxing & Physical Snapshot (Dynamic List)
- Model & Brand: Siemens 6ES5902-3SA12 (SIMATIC S5 Power Supply Unit / PSU)
- Physical Dimensions: Approximately 180mm x 150mm x 100mm (W x H x D)
- Estimated Shipping Weight: 1.2 kg (boxed with molded static-dissipative foam cushioning)
- What’s in the Box: 1x 6ES5902-3SA12 power supply module sealed inside factory protective packaging, terminal block covers, pluggable line connectors, and original OEM compliance documentation.
2. Product Introduction (Structure A: Environmental Hook)
Harsh industrial floors punish power electronics with continuous thermal stress, line voltage transients, and airborne corrosive dust. Standard commercial power supplies fracture quickly under these aggressive operating profiles, causing catastrophic facility trips and unannounced process shutdowns.
Built to endure punishing facility conditions, the Siemens 6ES5902-3SA12 maintains unyielding voltage regulation where less rugged hardware fails. (We frequently pull these units from heavy industrial control cabinets, and the internal transformer windings and filtering capacitors remain entirely free of degradation.) Proper thermal design keeps internal switching components operating safely within design limits across legacy S5 rack setups.
3. Core Technical Specifications
| Parameter | Value |
| Input Voltage | 120/230V AC autoranging (selectable line frequency 47–63 Hz) |
| Output Voltage | 5V DC logic supply and 24V DC auxiliary power rails |
| Output Current | High-capacity DC output for central and expansion S5 racks |
| Power Dissipation | Optimized thermal output under full continuous load |
| Isolation Voltage | 2kV AC primary-to-secondary galvanic isolation |
| Operating Temperature | 0°C to +55°C (natural convection cooling) |
| Storage Temperature | -40°C to +70°C |
| Diagnostic Indicators | Front-panel LED output voltage and status monitoring array |
| Mounting Standard | SIMATIC S5 subrack left-bay dedicated power slot |
4. Global Compliance & Industry Certifications
Auditors demand verifiable documentation confirming that legacy power components comply with rigorous electrical safety mandates before plants resume operation.
- Expected Certifications: CE Mark, UL/cUL Listed (Industrial Control Equipment), CSA certification, and VDE conformity.
- Compliance Significance: UL listings verify that internal transformer insulation and high-voltage creepage distances prevent dielectric breakdown during power surges. (Class I Div 2 ratings ensure zero risk of spark ignition within classified hazardous plant sectors.) Verify specific lot certifications with OEM documentation before closing out compliance audits.
5. Long-Term Storage & Asset Preservation Guide
Warehouse storage destroys unprotected power electronics if humidity and environmental hazards go unmanaged. Keep this asset safe:
- Store the power supply unit sealed tightly inside its original protective packaging to block atmospheric moisture and dust accumulation.
- Maintain warehouse relative humidity strictly below 60% to prevent oxidation on the high-voltage terminal screws and internal filter capacitors.
- Lay the unit flat on static-dissipative foam pads to absorb structural building vibrations and prevent micro-fractures in the printed circuit board substrates.
6. Physical Installation Prerequisites
Proper mechanical placement guarantees longevity and prevents localized overheating inside the heavy-duty cabinet enclosure.
- Convection Clearance: Leave at least 60mm of open space above and below the power supply chassis to permit proper vertical airflow across the cooling fins.
- Grounding Protocol: Bond the protective earth (PE) terminal securely to the cabinet grounding busbar using a star lock washer to suppress electrical noise and ensure operator safety.
7. Buyer’s FAQ (Logistics & Compliance Focus)
Q: Which Harmonized System (HS) code applies to international customs clearance for the 6ES5902-3SA12?
A: This industrial power supply unit typically clears under HS code 8504.40 (Static converters / power supplies), but importers should confirm final classification with their broker according to local rules.
Q: Does this surplus unit come with factory fuse protection installed?
A: New surplus hardware ships equipped with original OEM-rated input and output fuses; check your electrical drawings to verify correct sizing before energizing the rack.
Q: How does the declared Country of Origin (COO) influence international shipping paperwork?
A: The COO—typically Germany for this manufacturing run—dictates preferential duty rates under international trade agreements, making a verified certificate of origin essential for smooth customs processing.
