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One For All

TELE develops its best grid and system protection to date. Through flexible programming, the device can be adapted to the pre-installed standards of various countries and for individual requirements.

The new flexible TELE grid and system protection

With its new, optimized grid and system protection, TELE tackles an important problem: many countries – many standards. Effective immediately, the new RE NA003 with its compact design covers all main country standards in one device. All relevant parameters can be flexibly set directly in the field via Open Setup. This allows for permanently programmed, country-specific standards to be individually adapted, if required.

Completely new setups for new grid and system standards can also be easily programmed. For the first time, operation in single and three-phase grids is possible through simple switching. The new grid and system protection from Tele is suitable for medium and low voltages.


grid and system protection Tele RE NA003

Download short manual

Download manual

Country specific standards

Now  available: The new RE NA003 covers following country standards





  • Italy: CEI 0-21
  • Germany: VDE-AR-N 4105:2018-11, VDE-AR-N 4110:2018-11
  • Turkey, Belgium, France,…: VDE V 0126-1-1
  • Great Britain: G99/1 LV, G98/1
  • Belgium: C10-11 LV
  • Austria: OENorm E 8001-4-712 / E 8101-4-712
  • Europe, Denmark: EN50438

Download certificates


The characteristics of good grid and system protection

  • Functional safety
  • Voltage drop protection; overvoltage protection; monitoring of voltage quality
  • Frequency drop protection; Frequency rise protection
  • Detection of off-grid operation by phase voltage monitoring, RoCoF (Rate of change of frequency) and/or vector shift
  • Non-volatile fault latch
  • Random thresholds and reconnection times for non-adjustable energy producer (e.g. combined heat and power plant (CHP))
  • Wide rated voltage and rated frequency range (up to 60Hz), adjustable rated voltage
  • Free, practically unlimited parameterability
  • Software update option on site
  • Interfacing
  • Monitoring of 1 and 3 phase grids (with and without N)

Flexible parameterisation

The new grid and system protection has a wide-ranging power supply with an adjustable nominal voltage of 24 V DC, 110-240 V AC with up to 60 Hz nominal. Both the measuring as well as the supply circuits are designed for nominal voltages of up to 312 V AC. So the device can withstand an overvoltage of up to 35 percent.

Random thresholds and switching times for non-regulated energy producers, such as those which occur in combined heat and power units (CHP), for example, are no problem for the new grid and system protection. After each grid error the device calculates new random thresholds/values within random limits and shows them on the display. The big advantage of this method is that no feeder is discriminated against. This also prevents a destabilization of the grid by simultaneous switch-on or switch-off of multiple number of large energy producers.

The bodyguard guarantees safety

grid and system bodyguard

Grid and system protection is switched between a decentralized energy producer, such as a photovoltaic system, for example, and the grid of the public energy supply company (EVU) and continuously checks the grid quality. If the voltage or frequency in the public grid rises or falls beyond permissible limits, the small power station is immediately decoupled. In this way, any unintentional or “potentially dangerous” isolated operations are prevented from being carried out by maintenance personnel.

The corresponding parameters for this separation process are standardized differently in different countries. Now, for the first time TELE has brought grid and system protection to the market that can be freely configured in the field and thus can be individually adapted to your requirements. To prevent misuse, password protection or a sealing of the device is possible at the official delivery point.

Functional safety on board

The grid and system protection from TELE offers functional safety as a standard. Functional safety means that a single fault in the device may not lead to a loss of the safety functions. To ensure this, all components are implemented in duplicate in the device – every value is measured in parallel on both channels and constantly compared to ensure fault-free operation.

Isolated operation detection

The new grid and system protection from TELE offers functionally safe grid monitoring with protection for both voltage and frequency increases and decreases as well as the safe detection of isolated operation. Isolated operation detection is therefore possible in three different ways – phase voltage monitoring, RoCoF (Rate of Change of Frequency), or vector shift. Which of the three processes must be used is defined by the relevant applicable standard. Thus the new RE NA003 TELE grid and system protection covers all possible applications in one device.

You can find out where you can get the device under: Distribution


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