Automatically disconnects the plant from the grid when the voltage or frequency go outside the limits, so that the installation does not feed a downed grid. It comes with settings in accordance with ANRE Order 132/2020.
URNA0345-D is the relay that stands guard between your generating installation and the public grid. It permanently monitors the voltage and frequency at the connection point and, if these go outside the permitted limits, it commands the disconnection of the installation. The main purpose is that the generator should not continue to feed a section of the grid left without power - a dangerous situation both for the team working on the line and for the connected devices.
It is the device required by the distribution operator when connecting generating installations of over 30 kW, and here it comes with the settings already loaded in accordance with ANRE Order no. 132/2020, which considerably shortens parameterisation and commissioning. It is mounted in the electrical board, takes up little space (106 x 90 x 62 mm, 0.36 kg) and dissipates 6 W. By default it works with two contactors in series - the redundancy required by the connection regulations - but it can also be programmed for a single contactor or for a motorised circuit breaker, so it suits both new boards and existing installations being upgraded. Once set, it requires no routine intervention and works in a temperature range from -25 to +55 °C.
System and grid protection (NA-Schutz) / interface protection, with monitoring of line and phase voltages on maximum and minimum thresholds with associated time delays, of frequency on maximum and minimum thresholds with its own time delays and of the 10-minute average voltage. Configurable command schemes: two contactors in series (default), a single contactor or a motorised circuit breaker with undervoltage release, including in a configuration with UPS supply of the motorised breaker. Dimensions 106 x 90 x 62 mm, weight 0.36 kg, dissipated power 6 W, ambient temperature -25 ... +55 °C. The URNA0345 family is certified to the standards for connecting generators to low voltage, VDE-AR-N 4105 and DIN VDE 0126-1-1; EAN code 9004840963007.
Suitable for any photovoltaic, wind, micro-hydro or cogeneration plant connected to the low-voltage grid, especially over 30 kW, where the distribution operator requires interface protection.
| Function | system and grid protection (NA-Schutz) / interface protection |
|---|---|
| Monitored quantities | line and phase voltages (max/min), frequency (max/min), 10-min average voltage |
| Preloaded settings | in accordance with ANRE Order no. 132/2020 |
| Typical application range | generating installations of over 30 kW |
| Command schemes | 2 contactors (default), 1 contactor or motorised breaker with undervoltage release |
| Dimensions (w x h x d) | 106 x 90 x 62 mm |
| Weight | 0,36 kg |
| Dissipated power | 6 W |
| Ambient temperature | -25 ... +55 °C |
| Reference standards (URNA0345 family) | VDE-AR-N 4105, DIN VDE 0126-1-1 |
| EAN code | 9004840963007 |
Series-level specifications — valid for the product family
URNA0345-D is a system and grid protection relay (NA-Schutz / interface protection) which permanently monitors the grid parameters at the connection point of a generating installation and commands its disconnection when the parameters go outside the permitted limits. The main role is preventing islanded operation - the situation in which the generator continues to feed a section of the grid disconnected from the system, dangerous both for the intervention personnel and for the connected equipment.
The protection functions cover the monitoring of line and phase voltages on maximum and minimum thresholds, with associated time delays, the monitoring of frequency on maximum and minimum thresholds with its own time delays, as well as the supervision of the 10-minute average voltage. The relay is delivered with the settings preloaded in accordance with ANRE Order no. 132/2020, which significantly shortens the parameterisation and commissioning of installations with a power of over 30 kW in Romania.
The command scheme is configurable: by default it works with two contactors in series, the redundancy required by the connection regulations, but it can also be programmed for a single contactor or for motorised circuit breakers with undervoltage release, including in a configuration with UPS supply of the motorised breaker. In this way it adapts both to new boards and to existing installations being upgraded.
In terms of construction it is a device for mounting in the electrical board, with dimensions 106 x 90 x 62 mm, weight 0.36 kg, dissipated power 6 W and permitted ambient temperature between -25 and +55 °C. The URNA0345 family is intended for photovoltaic, wind, micro-hydro and cogeneration plants connected to the public grid, with certifications to the standards for connecting generators to the low-voltage grid (VDE-AR-N 4105, DIN VDE 0126-1-1).
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