HD design for Doepke’s residual current circuit-breaker –
Reliable protection even in harsh environments

Residual current circuit-breakers need to function with absolute reliability even in adverse conditions – in snow, rain, ice and extreme temperatures, and in contact with corrosive gases. In these situations, operators of electrical installations have two choices: they can protect the circuit-breaker from the outside or they can opt at the start for a residual current circuit-breaker that can withstand extreme conditions.

Doepke, the expert in RCD technology, has developed its HD design for harsh environments. HD stands for heavy duty and means that residual current circuit-breakers in this design can withstand high stresses – in other words they switch reliably even in extreme environmental conditions.

High-quality alloys and protective design
The design of Doepke’s HD switches and the special alloys used in their construction render them especially corrosion-resistant. The core component of the residual current circuit-breaker – the trip – is extremely durable and is not sensitive to environmental influences, regardless of where it is used. The trip is supported by other high-quality components, like the latch made from robust stainless steel. The Doepke residual current circuit-breakers in the HD design can withstand high temperatures and extreme temperature fluctuations. They continue to work reliably even if the temperature changes considerably inside the compact distribution board housing. The residual current circuit-breakers in the HD design are also significantly less sensitive to corrosive gases and mechanical stresses than conventional circuit-breakers.

No compromises when it comes to functional protection
Often, protective devices are built into distribution boards which are intended to provide the best possible climate conditions for a residual circuit current-breaker inside the distribution board. This also works well against mechanical stresses such as dust. However, even the best enclosure is not physically capable of providing 100% protection against harmful environmental influences such as aggressive corrosive gases. Residual current circuit-breakers will come into contact with undesirable environmental influences when they need to be opened for maintenance or repair work, if not before. This is not the case with Doepke HD, which acts as its own enclosure.

Purely external solutions quickly reach their limits when it comes to corrosion protection as it is not possible to completely prevent condensation, i.e. the formation of moisture or corrosive acids on metal parts, inside the distribution board. But the issue is that the most important parts of the residual current circuit-breaker – the trip and latch – are made of metal. If they rust, it can no longer be guaranteed that the residual current circuit-breaker will function properly. Corrosion protection is ensured with Doepke’s residual current circuit-breakers in the HD design as noble metals and special alloys are used in their construction.

Low temperatures and moisture caused by condensation can be counteracted by the use of heating elements. These do of course require electricity. If the power is turned off, the residual current circuit-breaker is no longer protected. This may occur when the building-site distribution board is between sites and not in use.  Doepke’s residual current circuit-breakers in the HD design have a clear advantage here too: their special design means that they are protected at all times – even when they are disconnected from the power supply.

Wide range of applications and large product range
Residual current circuit-breakers in the HD design can be used in a wide range of areas:
in places with extreme climate conditions such as cold stores, electric vehicle charging stations and in building-site distribution boards. HD circuit-breakers then continue to work reliably when they are used in areas where corrosive gases or condensation could occur. This could be the case, for example, on farms, in businesses in which solvents are processed (printers’ and paint shops, for example) and at swimming pools and spas.
When choosing a Doepke HD residual current circuit-breaker, there’s no need to consider limitations in the technical data: in principle, all Doepke residual current circuit-breakers are available in an HD design as well – from the pulsating and AC sensitive Type A to AC-DC sensitive Type B.