S13-M Series Low-Loss Oil-Immersed Distribution Transformer

Our switchgear is designed and manufactured in full compliance with the international IEC 61439 series of standards (specifically IEC 61439-1 & -2). We also hold complete Type Test Certification (TTA) from an independent, accredited laboratory to validate the performance and safety claims. Our products also meet relevant national standards such as GB7251.1.

Form 4B is a classification per IEC 61439 that specifies the highest degree of internal separation within the assembly. It ensures complete isolation between the busbars, functional units (like circuit breakers), and outgoing terminal compartments. This enhances safety by containing any potential internal fault arc, allows for safer maintenance, and prevents faults in one unit from affecting others.

A withdrawable design allows for the circuit breaker to be easily disconnected, isolated, and physically moved to a "test" or fully "withdrawn" position without de-energizing the entire panel. This enables safe and rapid maintenance, testing, or replacement of the breaker, significantly minimizing downtime for critical power systems.

Our standard panels are rated for a short-time withstand current (Icw) of 50kA for 1 second. This means the assembly can withstand the thermal and electromagnetic stresses of a short-circuit fault of that magnitude for the specified time, allowing the upstream protective device to clear the fault without catastrophic failure. Higher ratings can be engineered for specific projects.

For standard configurations, the lead time is typically 4-6 weeks. For fully customized projects involving complex engineering, the lead time can range from 8 to 12 weeks. We provide a precise timeline upon finalization of the technical specifications and single-line diagram.