Question 1

Is SIVACON S8 type-tested to IEC 61439 and what are its rated current and short-circuit limits?

Accepted Answer

Yes—SIVACON S8 is a Siemens IEC 61439 type-tested switchboard platform. The system has documented type-test combinations with rated currents up to 7,400 A for the busbar system; short-circuit withstand capability depends on the selected configuration and busbar system but is published in Siemens type-test certificates (commonly reaching into the 100–150 kA range for certain designs). Always refer to the specific SIVACON S8 type-test report and data sheet for the Icw (short-time withstand), Ipk (peak current) and making capacity values applicable to your busbar and device configuration. Compliance to IEC 61439-1/-2 is demonstrated by the manufacturer when using validated combinations.

Question 2

How do I incorporate 3VA/3WA breakers into an IEC 61439 panel to ensure compliance?

Accepted Answer

3VA and 3WA breakers are Siemens circuit-breaker families designed under IEC 60947-2. To ensure IEC 61439 compliance, select breakers whose rated operational current (In), rated short-circuit breaking capacity (Icu/Ics) and thermal performance match the panel’s design verification. Confirm that the chosen breaker is included in the panel’s type-tested combination or perform design verification calculations (temperature rise, dielectric, and short-circuit tests) if using a non-type-tested combination. Ensure proper mounting, busbar clearances, segregation barriers (form of separation), and coordination for selective tripping per IEC 61439 clauses and manufacturer installation instructions.

Question 3

Which forms of separation (1–4b) are recommended for Siemens MCC and PCC applications?

Accepted Answer

IEC 61439 defines Forms of Separation 1, 2, 3, 4a and 4b. For Siemens MCCs (motor control centers) and PCCs (power control centers), Form 4b (full segregation of functional units including separation of busbar, cable, and functional unit compartments) is commonly preferred for safety, maintainability and to enable withdrawable units such as MNS or SIVACON withdrawable feeders. Form 3 is often used when segregating busbars from functional units is sufficient. Choice depends on operational requirements: 4b offers the highest level of internal segregation and fault containment, facilitating safer live-work practices and easier selective maintenance in accordance with IEC 61439-1/-2 guidance.

Question 4

What installation practices are required to integrate SINAMICS drives in an IEC 61439-compliant VFD panel?

Accepted Answer

Integrating SINAMICS VFDs in IEC 61439 panels requires EMP/EMC mitigation, thermal management, and segregation. Fit EMC filters, dv/dt filters or sinusoidal output filters as recommended by Siemens to reduce interference; separate drive control circuits from power circuits and provide dedicated cooling or ventilation per published thermal limits. Verify short-circuit withstand at the drive feeding point and ensure upstream protection coordination (fuses or breakers rated per IEC 60947) to protect IGBT modules. Include harmonic mitigation (filters or active front ends) if required by site power quality standards. Document all component ratings to preserve the panel’s design verification per IEC 61439-1.

Question 5

Can Siemens MNS be used for data center main distribution and what are its advantages?

Accepted Answer

Yes—Siemens MNS is a modular, type-tested switchgear platform suitable for data center main distribution. MNS provides high modularity, withdrawable and service-friendly units, extensive segregation options (Forms 3 and 4b), and compact busbar designs that support redundancy (A/B feeders) and parallel feeds. Advantages for data centers include predictable type-tested short-circuit performance, simplified maintenance through withdrawable feeders, and compatibility with busbar trunking systems and redundant UPS/generator interfaces. Validate the specific MNS type-test report for the required rated current and short-circuit levels in your design and confirm integration with metering and BMS via SIPROTEC/SENTRON and IEC 61850 or Modbus gateways.

Question 6

How should I specify short-circuit ratings for a Siemens-based PCC according to IEC 61439?

Accepted Answer

Specify short-circuit ratings by defining the required rated short-time withstand current (Icw) and peak withstand (Ipk) for the assembly, matching or exceeding the expected prospective fault currents at the point of installation. Use Siemens type-test certificates for SIVACON/MNS and component data (3VA/3WA breakers) to select devices and busbar systems whose rated Icw/Ipk preserve the type-test envelope. Per IEC 61439, document making capacity, conditional short-circuit current and coordination measures. If a non-type-tested combination is used, perform design verification calculations or tests (short-circuit, temperature-rise) as required by the standard.

Question 7

Which Siemens devices are recommended for metering, protection and communications in IEC 61439 assemblies?

Accepted Answer

SENTRON (compact energy meters and measuring relays), SIPROTEC (protection relays), and SICAM (communication and substation automation) are Siemens’ primary offerings for metering and protection. SENTRON devices provide DIN-rail and panel-mounted energy measurement per IEC 62053 classes; SIPROTEC relays handle overcurrent, differential and motor protection with IEC 61850 communication; SICAM and other gateways enable Modbus, PROFINET and IEC 61850 integration. Use manufacturer configuration files and apply proper segregation and mounting to comply with IEC 61439 wiring and clearances, and to ensure accurate metering and relay performance.

Question 8

Are Siemens SIRIUS contactors and other components available with Ex/hazardous-area approvals?

Accepted Answer

Siemens offers Ex-rated and ruggedized variants for certain products, but availability depends on product family and regional certifications. Equipment for hazardous locations must comply with IEC 60079 series (explosion protection) or equivalent regional standards (ATEX, IECEx). For SIRIUS contactors and SINAMICS drives, check Siemens product documentation and certificates for explicit Ex/ATEX approvals and installation restrictions. When designing IEC 61439 panels for hazardous areas, use certified Ex equipment, adhere to zone separation practices, and apply installation methods (remote mounting, purging, or use of Ex enclosures) as specified in IEC 60079 and local regulations.

Siemens

Panels Built with Siemens

Industries

Frequently Asked Questions

Request a Quote