Industries
Network equipment for utilities and infrastructure
Ring main units, transformers and substations for independent network contractors, specified to the standard of the operator that will adopt the assets.
The equipment chain
- 01NetworkThe operator's medium voltage cable ring, fed from both ends, so a faulted section can be isolated and supply restored from the other side.
- 02Ring main unitTwo ring switches and a transformer feeder in one unit. The ring switches isolate the cable section on either side of the node.
- 03TransformerBuilt to the operator's standard: the voltage pair, losses, vector group and connection system come from its specification, not from the buyer.
- 04LV cabinetSplits the transformer's output into low voltage feeders, each protected by fuses sized to its cable.
- 05ConsumersHomes and businesses on the low voltage feeders. Their combined demand and its expected growth set the rating the operator chooses.
Equipment that joins a public network is built to the network operator's standard, and many operators accept only equipment types they have assessed. When you build assets for adoption, the operator's specification is your specification. An offer that departs from it is of no use, however good it looks.
We source to the operator's standard. Each quotation states whether the operator concerned has assessed the type offered, so you know before you order.
In Great Britain the route is set by Ofgem's competition in connections. Contestable work, such as a new secondary substation, can be built by an Independent Connection Provider accredited under NERS and then adopted by the distribution network operator or an independent network operator. Reinforcement of the existing network stays with the operator. In Dubai, DEWA's medium voltage network runs at 6.6, 11, 22 and 33 kV, with 11 kV the most used, and its standards keep supply variation within 5 % at medium voltage and 6 % at low voltage.
What decides the specification
The network operator's standard decides the ring main unit configuration, the transformer ratings and losses, the connection systems and often the enclosure. Where the operator keeps a list of accepted types, that list governs which equipment can be offered.
Beyond the standard, the network design decides the ratings: the ring configuration, the fault level and the load of the area served.
What to settle early
| Consideration | Why it matters here |
|---|---|
| Operator standard | Governs the specification of adopted assets |
| Accepted equipment types | Where an operator keeps a list, it decides what can be offered |
| Ring configuration | Sets the ring main unit functions |
| Network automation | Decides motorised operation and monitoring |
| Pad mounted or prefabricated | Follows the network's practice |
| Insulating gas | EU rules restrict fluorinated gas in new distribution switchgear |
Equipment for this application
What we need to quote
- The network operator and its equipment standard
- Whether the asset will be adopted by the operator
- Ring main unit configuration and operation
- Transformer ratings and voltages
- Quantities and the delivery programme
Building or expanding a facility?
Send the whole equipment schedule as one project, each item with its own requirements.