3DN
Centre/double-side break disconnector 3DN1/3DN2, 40.5–550 kV, up to 5,000 A / 63 kA, motor or manual drive
3DN
- Cylindrical self-resilient contact fingers with AgC (silver-graphite) coating: spring-free contact force, dry lubrication, self-cleansing — 25-year maintenance interval
- Centre break for large phase distance and versatile layouts; double-side break for substations with limited phase spacing, self-interlocked end position, applicable also in indoor installations
- High short-circuit capability: up to 63 kA short-time / 160 kA peak withstand, with ice-breaking behavior (icing class 10/20 mm, −55 to +55 °C)
- Motor/manual operation via 3DV6/7 (aluminium cast housing) or 3DV8 smart-design (stainless-steel housing) drives, both IP 55 and maintenance-free; hand-crank shutter automatically interrupts the motor and control circuit for safe manual operation
- Optional add-on earthing switches (laterally or integrated) and bus-transfer current capability of 1,600 A; arc restrictors type-tested per IEC 62271-102 Annex B with more than 100 making/breaking operating cycles
Open-air substation isolationParallel, diagonal and in-line busbar arrangementsSubstations with limited phase distanceBus-transfer current switchingIndoor high-voltage installations
Sign in to see your price, availability and framework terms for 3DN.
Horizon-3 pattern: this exact page gains commerce powers on sign-in — the URL never changes.
SIMULATED · ASK-AN-EXPERT PILOT DEMO
Ask an expert about 3DN
15 minutes with the right switchgear specialist — question in, booked call out. No email archaeology.
Checking availability…
3DN covers 40.5–550 kV of the disconnectors range (≤ 550 kV across the category, √ scale).
Specifications
Main
| Product family | 3DN high-voltage disconnectors, air-insulated (AIS) |
| Types | 3DN1 centre-break (DBF / CR series); 3DN2 double-side break (ZBF / DR series) |
| Design | 3DN1: two rotatable insulators per pole, current path opens to the side; 3DN2: three support insulators, centre column rotating with current path |
| Application | Open-air substations; 3DN1 for parallel, diagonal or in-line arrangements; 3DN2 where phase distance is limited or vertical opening is not possible |
| Operating mechanism | Motor or manual operation — 3DV6/7 motor drive or 3DV8 smart-design motor drive with hand crank |
| Attachments | Built-on earthing switches (lateral or integrated arrangement); bus-transfer contacts / arc restrictors |
| Maintenance interval | 25 years |
Electrical
| Rated voltage | 40.5 / 72.5 / 123 / 145 / 170 / 245 / 300 / 362 / 420 / 550 kV |
| Rated normal current | Up to 4,000 A (3DN1); up to 5,000 A (3DN2) |
| Rated short-time withstand current | Up to 63 kA, rated duration 1 s / 3 s |
| Rated peak withstand current | Up to 160 kA |
| Lightning impulse withstand (1.2/50 µs), to earth | 185 kV (40.5 kV) … 1,550 kV (550 kV); across isolating distance 215 … 1,550 (+315) kV |
| Power-frequency withstand (50 Hz/1 min), to earth | 80 kV (40.5 kV) … 620 kV (550 kV); across isolating distance 90 … 800 kV |
| Switching impulse withstand (250/2500 µs), ≥300 kV | 850 … 1,175 kV to earth; 700 (+245) … 900 (+450) kV across isolating distance |
| Bus-transfer current capability | Optional, 1,600 A |
Mechanical / environment
| Contact system | Cylindrical self-resilient contact fingers, AgC coating; spring-free, dry-lubricated, self-cleansing |
| Ambient temperature range | −55 … +55 °C |
| Icing class | 10 / 20 mm |
| Base / corrosion protection | Hot-dip galvanized steel base frame withstanding high mechanical and terminal loads; seismic-capable design |
| Motor drive (3DV6/7, 3DV8) | Rated torque 600 / 800 Nm; operating time < 15 s; protection class IP 55; maintenance-free |
| Control voltage | 60/110/125/220 V DC; 110/125/220…230 V AC 1~ or 220/380/415 V AC 3~, 50/60 Hz |
| Delivery | Pre-assembled, pre-adjusted disconnector poles from the factory; erection with standard tools only |
Standards & certifications
| Product standard | IEC 62271-102 (high-voltage disconnectors and earthing switches) |
| Additional standards | Exceeds IEC requirements; meets GOST R and GB/DL standards |
| Auxiliary switch | Switching capability Class 2 according to IEC 62271-102 |
| Induced-current switching (earthing switches) | If required, per IEC 62271-102 Class A or Class B |
| Bus-transfer / arc restrictors | Type-tested per IEC 62271-102 Annex B, > 100 making/breaking operating cycles |
| Quality management | ISO 9001-certified manufacturing |
Options & variants
Rating steps shown are the catalog technical-data columns for common transmission voltage levels; all values in accordance with IEC, other values on request. Drive (3DV6/7 or 3DV8), earthing-switch and bus-transfer options are configured per order.
| Type | Rated voltage | LIWV 1.2/50 µs (to earth) | Rated normal current | Short-time / peak withstand |
|---|---|---|---|---|
| 3DN1 centre break | 123 kV | 550 kV | up to 4,000 A | up to 63 kA / 160 kA |
| 3DN1 centre break | 145 kV | 650 kV | up to 4,000 A | up to 63 kA / 160 kA |
| 3DN1 centre break | 245 kV | 1,050 kV | up to 4,000 A | up to 63 kA / 160 kA |
| 3DN2 double-side break | 245 kV | 1,050 kV | up to 5,000 A | up to 63 kA / 160 kA |
| 3DN2 double-side break | 420 kV | 1,425 kV | up to 5,000 A | up to 63 kA / 160 kA |
| 3DN2 double-side break | 550 kV | 1,550 kV | up to 5,000 A | up to 63 kA / 160 kA |
Documents & downloads
Catalog Disconnectors and earthing switches — SHVC brochure with 3DN-series technical data (EN, 2025)
Catalog HV disconnectors & earthing switches — catalogue Brazil (2022)
Catalog HV disconnectors & earthing switches — catálogo Brasil (2022)
Brochure AIS disconnector spares — Global Parts Services
Brochure Disconnectors and earthing switches — Siemens Energy Brazil brochure (current online edition)
Ordered designations
Representative orderable type designations of this family — searchable via the catalog search.
Related products
3DN0/4/6/7/8 
3DN5
Disconnectors and earthing switches 3DN0/4/6/7/8, 40.5 kV up to 550 kV, rated normal current up to 5000 A, short-time withstand up to 63 kA, motor or manual operation
40.5 kV up to 550 kV across earthing-switch and disconnector variants · Rated normal current up to 5000 A (3DN4), short-time withstand up to 63 kA · Spring-free AgC contact system, 25-year maintenance interval Datasheet · Dimensions ↓ 3DN3Pantograph disconnector 3DN3, scissor design, up to 5,000 A, peak withstand up to 160 kA, PRF2/PRL2 (PR series)
Up to 5,000 A · Peak withstand up to 160 kA · Scissor (pantograph) design Datasheet · Dimensions ↓ 3DN5