Three-phase isolation transformer 230 V / 230 V + N
3 × 230 V isolation · creates a neutral · vector group Dyn11 · 1 to 100 kVA · made in France
No reviews of this model yet5 kVA12.6 A per phase on the secondary
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- 5-year warranty · wound and tested in Gailhan
Key features
This three-phase transformer isolates your installation from a 3 × 230 V supply without changing the voltage, and gives it a neutral. On 3 × 230 V supplies without a neutral — IT systems in Belgium and Norway, older 220 V three-phase installations — it lets you switch to a TN-S system, with the neutral connected to earth, or create an isolated section with an insulation monitoring device. Vector group Dyn11, electrostatic shield as standard, 1 to 100 kVA in IP00, IP23 or IP54, and 125 to 1,000 kVA on request: it is wound and tested in our workshop in Gailhan (Gard, southern France).
On this three-phase transformer, the neutral is there for the earthing system, not for supplying single-phase 230 V appliances. To get 230 V between phase and neutral on a 3 × 230 V supply, choose the 230 V → 400 V + N model.
The earthed shield limits the transfer of disturbances between the supply and your installation, and the delta primary winding traps the third harmonics generated by your loads. It does not correct low supply voltage or a power cut.
Neutral connected to earth: TN-S system, protection by RCDs. Isolated neutral: IT system, which requires an insulation monitoring device. The 230 V to 230 V isolation transformer suits both.
When should you use a 230 V / 230 V three-phase transformer?
- Converting a 3 × 230 V installation from an IT system to a TN-S system, so that it can be protected by RCDs.
- Creating a monitored isolated section for equipment that must not trip on a first fault.
- Shielding PLCs, CNC controls or laboratory equipment from supply disturbances.
- Using a three-phase transformer to isolate the output of a 3 × 230 V generator or UPS from the installation it backs up.
It works at 50 Hz, or at 60 Hz on confirmation. It is not suitable for 400 Hz supplies.
Specifications of the 230 V / 230 V + N three-phase transformer
Values for the selected configuration: 5 kVA · IP23.
- Phase-to-phase voltage
- 3 × 230 V
- Connection
- Delta (Δ)
- Rated line current
- 12.6 A
- Terminals
- 1U 1V 1W + PE
- Phase-to-phase voltage
- 3 × 230 V
- Connection
- Star with neutral (YN)
- Rated line current
- 12.6 A
- Phase-to-neutral voltage
- 133 V
- Terminals
- 2U 2V 2W 2N + PE
- Type
- Dry-type transformer, natural cooling
- Core
- 3 limbs, one coil per phase
- Insulation class
- H (180 °C)
- Electrostatic shield
- Fitted as standard, earthed
- Standards
- EN IEC 61558-1 and EN IEC 61558-2-4
- IP rating
- IP23, ventilated metal enclosure
- Overall dimensions L × W × H
- 525 × 320 × 550 mm
- Weight
- 131 kg
- Mounting
- 2 feet, holes Ø 12 mm
- Ambient temperature
- 40 °C maximum
From 63 to 100 kVA, losses and efficiency are available on request.
Ratings and prices
From 1 to 100 kVA. Above that, on request.
| Rating | Current | Recommended circuit breaker | No-load / load losses | Efficiency | Weight | Dimensions (mm) | Price ex VAT | Dispatch |
|---|---|---|---|---|---|---|---|---|
| 1 kVA | 2.5 A | D 4 A | 12 / 58 W | 93.4 % | 12 kg | 340 × 310 × 350 | €381.58 | 3 days |
| 2 kVA | 5.0 A | D 6 A | 22 / 107 W | 93.9 % | 20 kg | 340 × 310 × 350 | €430.75 | 3 days |
| 2.5 kVA | 6.3 A | D 10 A | 24 / 130 W | 94.2 % | 22 kg | 340 × 310 × 350 | €448.25 | 3 days |
| 3.15 kVA | 7.9 A | D 10 A | 30 / 143 W | 94.8 % | 26 kg | 340 × 310 × 350 | €467.42 | 3 days |
| 4 kVA | 10.0 A | D 16 A | 42 / 240 W | 93.4 % | 40 kg | 460 × 320 × 500 | €665.75 | 3 days |
| 5 kVA | 12.6 A | D 16 A | 51 / 261 W | 94.1 % | 46 kg | 460 × 320 × 500 | €694.92 | 3 days |
| 6.3 kVA | 15.8 A | D 20 A | 59 / 281 W | 94.9 % | 52 kg | 460 × 320 × 500 | €736.58 | 3 days |
| 8 kVA | 20.1 A | D 25 A | 90 / 281 W | 95.6 % | 74 kg | 525 × 335 × 550 | €1,031.58 | 3 days |
| 10 kVA | 25.1 A | D 32 A | 98 / 322 W | 96.0 % | 81 kg | 525 × 335 × 550 | €1,094.92 | 3 days |
| 12 kVA | 30.1 A | D 32 A | 114 / 353 W | 96.3 % | 92 kg | 525 × 335 × 550 | €1,425.75 | 3 days |
| 16 kVA | 40.2 A | D 50 A | 131 / 412 W | 96.7 % | 105 kg | 525 × 335 × 550 | €1,432.42 | 3 days |
| 20 kVA | 50.2 A | D 63 A | 147 / 518 W | 96.8 % | 116 kg | 525 × 335 × 550 | €1,514.92 | 3 days |
| 25 kVA | 62.8 A | D 80 A | 155 / 574 W | 97.2 % | 126 kg | 525 × 335 × 550 | €1,686.58 | 3 days |
| 30 kVA | 75.3 A | D 80 A | 134 / 621 W | 97.5 % | 120 kg | 700 × 480 × 720 | €1,854.08 | 3 days |
| 40 kVA | 100.4 A | D 125 A | 150 / 882 W | 97.5 % | 132 kg | 700 × 480 × 720 | €2,255.75 | 3 days |
| 50 kVA | 125.5 A | MCCB 160 A | 206 / 892 W | 97.9 % | 173 kg | 700 × 480 × 720 | €2,383.25 | 3 days |
| 63 kVA | 158.1 A | MCCB 200 A | —* | —* | 220 kg | 700 × 480 × 720 | €3,789.92 | 6 days |
| 80 kVA | 200.8 A | MCCB 250 A | —* | —* | 300 kg | 700 × 480 × 720 | €4,591.58 | 6 days |
| 100 kVA | 251.0 A | MCCB 315 A | —* | —* | 345 kg | 700 × 480 × 720 | €5,358.25 | 6 days |
| 125 to 1,000 kVA | On request, in the standard ratings: 125, 160, 200, 250, 315, 400, 500, 630, 800 and 1,000 kVA. Request a quote | |||||||
Rated current: primary = secondary (1:1 ratio). Type D circuit breaker on the primary. Losses and efficiency: design values at full load. * 63 to 100 kVA: losses and efficiency on request. Prices exclude carriage. Calculator formula: kVA = √3 × 230 V × A ÷ 1,000 (current on the 230 V side), next standard rating up.
Wiring diagram and enclosure drawing
Extracts from the datasheet: coil-by-coil connections and enclosure dimensions.
Installation and protection
Values for 25 kVA. Sizing of the installation remains the installer's responsibility.
Upstream protection
Type D circuit breaker 40 A
or aM fuses 40 A · inrush current ≈ 433 A peak
Secondary neutral
- Earthed: TN-S system, the most common.
- Isolated from earth: IT system, with an insulation monitoring device.
Safety
- Connection by a qualified person.
- Earth connected before switching on.
- IP00: in a cabinet or a closed electrical room.
Standards, warranty and options
A standard transformer, built to order and adaptable to your installation.
Frequently asked questions
About the 230 V / 230 V + N three-phase isolation transformer.
Why use a 230 V / 230 V three-phase transformer if the voltage stays the same?
To isolate: the secondary no longer has any electrical connection to the supply, and you choose its earthing system (TN-S or IT) independently of the network operator's. It is also a barrier against disturbances.
Can I get 230 V between phase and neutral?
No: on this model, the neutral is at 133 V from the phases. For 230 V between phase and neutral from a 3 × 230 V supply, choose the 230 V → 400 V + N model.
How do I convert from an IT system to TN-S?
By connecting the secondary neutral (terminal 2N) to earth at the transformer, then protecting the outgoing circuits with RCDs. The system design is your electrician's responsibility.
How do I wire a 230 V / 230 V three-phase transformer?
Primary connection: the supply goes to terminals 1U, 1V and 1W, earth to PE; the delta connection is made at the factory. On the secondary, the outgoing circuits leave from terminals 2U, 2V and 2W, and the neutral from terminal 2N. The full wiring diagram is on the datasheet.
Which rating should I choose?
To choose your 230 V / 230 V three-phase transformer, multiply the current per phase on the 230 V side by 230 V and by √3, then take the next standard rating up. For 32 A per phase: 12.7 kVA, so a 16 kVA unit. The calculator above the table does this for you.
Do you make three-phase transformers above 100 kVA?
Yes, on request: we also make this 230 V / 230 V three-phase transformer from 125 to 1,000 kVA, in the standard ratings 125, 160, 200, 250, 315, 400, 500, 630, 800 and 1,000 kVA. Choose the rating at the top of the page, below the priced ratings, or request a quote: reply within 48 h.
What upstream protection should I install?
On the primary (230 V) of your 230 V / 230 V three-phase transformer, a type D circuit breaker or aM fuses sized for the rated current: for 5 kVA, 12.6 A per phase, i.e. a 16 A type D circuit breaker or 16 A aM fuses. At switch-on, the inrush current reaches about twelve times the rated current; the rating for each size is given in the table.
IP00, IP23 or IP54: which should I choose?
IP00: open-frame transformer, to be installed in a cabinet or a closed electrical room. IP23: ventilated enclosure, for a plant room sheltered from water. IP54: closed enclosure, protected against dust and splashing water.
What are the lead times?
From 1 to 50 kVA, dispatched from our workshop within 3 working days; from 63 to 100 kVA, within 6 working days. Up to 30 kg, the transformer ships as a parcel, with free delivery within France. Heavier units travel on a pallet with Kuehne + Nagel: 48 to 72 hours in mainland France, 96 hours elsewhere in Europe; pallet delivery is free from €1,000 ex VAT, otherwise a flat €50 ex VAT.
Customer reviews
No reviews of this model yet. Here is what customers say about another three-phase transformer built the same way (reviews in French).
Livraison rapide, produit conforme et bien emballé. Installation sans difficulté, parfait pour créer un neutre. Le service téléphonique est top, fabrication française en plus. Je recommande sans hésiter.
Produit reçu rapidement, très bien emballé. Fonctionne parfaitement sur notre installation industrielle. Fabrication sérieuse, rien à signaler après plusieurs semaines d'utilisation. Content d'acheter français.
Produit conforme à la description, fabrication robuste et délai respecté. Service client à l’écoute, installation réalisée sans souci. Très satisfait de la qualité, matériel professionnel, rien à dire de plus.
Other three-phase transformers
Built the same way, for other voltages.