News

Previously, three single-phase OLTCs were used to fulfil the insulation requirement above 145 kV for a Delta application. This configuration was commonly used among all OEMs. 
With the introduction of RSV12 D 400A 170 kV, VOLTAP engineers have achieved a breakthrough in insulation level up to 170 kV in a three-phase, single-column design.
This innovation replaces three single-phase OLTCs with one compact integrated unit, the first of its kind in the OLTC market.
Points that make it unique.
1. One OLTC That Replaces Three
The RSV12 enables transformer OEMs to:
•    Use a single compact OLTC instead of three units.
•    Reduce transformer tank size, lowering oil volume, steel mass, and assembly complexity.
•    Lower overall transformer cost, improving competitiveness in tenders.
This single-column, three-phase concept simplifies transformer construction and boosts design efficiency - while maintaining VOLTAP’s renowned mechanical and electrical reliability.
2. Optimized for Delta Connection
Purpose-built for delta-connected transformers, the RSV12 ensures synchronized three-phase switching, delivering balanced voltage control and stable performance.
Ideal for:
•    Industrial power transformers
•    Power transformers 
•    Compact substation transformers requiring reduced footprint
3. Maintenance Time Reduced by 70%
•    Only one OLTC to inspect, overhaul, or replace, instead of three.
•    Maintenance duration reduced to one-third.
•    Lower spare parts inventory and reduced labor cost.
Result: less downtime, lower maintenance expenses, and faster power restoration for end users.
4. Dual Advantage - For OEMs and Utilities
Stakeholder Key Benefit

• • Transformer OEMs: Smaller tank, simplified piping, fewer penetrations, shorter assembly time, and lower production cost.
  • End Users / Utilities: Reduced maintenance cost, faster service turnaround, and improved transformer availability.

5. VOLTAP - a step ahead
The RSV12 establishes a new benchmark in OLTC design for Delta applications, a unique three-phase single-column OLTC engineered for high-voltage delta applications.
With this achievement, VOLTAP further strengthens its position as a reliable and robust OLTC manufacturer in Europe.