GRAVITYline standard dry-type distribution transformers

SGB's Gravity range of encapsulated dry-type transformers has been specifically designed to meet the needs of the distribution sector of the French electrical market. Based on the SGB wire layer technology and their 50 years of experience in transformers, the Gravity range combines a highly standardized design with an optimized production line automation.

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SANERGRID offers you the GRAVITYline range, a standardized range of dry-type transformers for electrical distribution from 160 to 2500 kVA, in 24kV insulation class; in step-down and step-up 20kV/0,41.   ECODESIGN or ECO DESIGN - Conformity with European standard EU 548-14 (reduced losses - 1 July 2021). The dry-type transformers do not contain any flammable dielectric oil and do not require a retention tank or a fireproof tank. They are widely used in industry, hospitals, tunnels, supermarkets and establishments receiving the public.


Many accessories are available, PT100, PTC, T119 relay, T154 relay or ZIHEL relay, SanerVib® anti-vibration silent block, IP31, IP 33 protection enclosures, plug-in terminals, fans, etc.

Advantages of GRAVITYline transformers

SGB GRAVITYline dry-type transformers have the advantage of not using dielectric oil, they do not need a fireproof containment tank. Their special resin self-extinguishes the fire and requires little maintenance.  This is why GRAVITYline dry-type transformers are mainly used in public buildings such as hospitals, stadiums, schools, buildings, offices, factories, airports, train stations and other buildings. But also for electrical distribution needs where protection against fire risk is identified, such as data centers, tunnels, petrochemical sites, power plants, etc.

Our own test equipment

SGB's encapsulated dry-type transformers are designed as C4*E3F1 and manufactured in series according to IEC 60076-11.

The tests defined in the standard for routine and type tests are carried out on our own modern test bench according to international standards:

- Individual routine tests

- But also special type tests:

  •          Noise measurement
  •          Certification of the climatic class - C2/C3/C4
  •          Certification of environmental class - E2/E3/E4

- Special external tests:

  •          Fire behavior test (destructive test) F1
  •          Dynamic short-circuit test according to IEC and GOST 

All our GRAVITYline transformers comply with the European ECODESIGN EU 548-14 standard for reduced loss levels from July 2015 and July 2021 (ECODESIGN Tier 2) for transformers in the European Union.

For higher loss classes and export markets please contact us.

Ask us for a custom design for your specific needs.

Standard configuration SANERGRID® GRAVITYline Tier 2:

Primary voltage: 20kV, secondary voltage (no load): 410/230 V - unreduced neutral | ECODESIGN EU548-14 Tier 2 | classification: C4*E3F1| frequency: 50 Hz | coupling: DYN 11 | short circuit voltage: 6% | rated insulation voltage: 24 kV | withstand voltage at 50 Hz for 1 minute: 50 kV | rated impulse withstand voltage : 95kV | natural cooling in ambient air (temperature at 40°C) | MV insulation asphalt/LV impregnated | thermal class F | de-energized setting on MV side +/- 2x2,5 per strip | HV connection on strips | LV connection on strips 

Standard accessories included: 4 lifting rings, 4 adjustable rollers, thermal protection device by default : T-154 and 3 PT100 probes (or on request T119 with 6 PTC probes), earth terminal.

Transformer performance certified by factory test certificate.

All GRAVITYline transformers are guaranteed for 2 years after delivery.

SGB gammes de transformateur sec de distribution
Download the brochure of the standard range of SGB distribution transformers SANERGRID Gravity Line by CLICKING HERE

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