NA003 from TELE complies with VDE-AR-N 4105: 2018-11 and British G98/99
At a glance
The newly revised grid and system protection NA003 from TELE fulfills all regulations of the new VDE-AR-N 4105: 2018-11 as well as the British G98 and G99 and can easily be installed in all plants and systems. Please bear in mind, that this device not only protects the network but also secures your financial investment of the plant and installed machinery. The application rule “Power generating plants in the low-voltage grid” (VDE-AR-N 4105) has been revised and now requires higher demands than before. The British “Engineering Recommendations” G98 and G99 also require a new set of parameters.
New functions for NA003
Starting with April 27th, 2019, power generation plants on the low-voltage grid must comply with the strict rules of VDE-AR-N 4105: 2018-11. For this reason, the grid and system protection device NA003 from TELE offers three different parameter sets for operations in Germany:
- Pn ≤ 50 kW: Stirling generators/fuel cells, directly or via an inverter, coupled synchronous and asynchronous generators.
- 50 kW <Pn <135 kW: Directly coupled synchronous and asynchronous generators.
Coupling switch: Only one coupling switch has to be used. However, only tie-breakers may be used in which, when switched on, a control voltage must always be present and automatically switches off when this voltage is not present. ATTENTION: The exception is an application with inverters; in this case, still two coupling switches must be used.
Switching on: If a fault in the coupling switch was detected, via the mandatory return contacts, the NA003 may only switch on again, when a reset is activated via the keypad and both the voltage U and the frequency f are in good conditions for more than 60 seconds. Additional an error of the coupling switch is reported via relay 3 output to the generation plant. This ensures that e.g. even with welded contacts of the coupling switch no power is fed into the grid. The “turn-on” threshold for f has been increased from 50.05Hz to 50.10Hz.
Further new parameters
Switch-off thresholds U, f: The modification of the parameters has been severely restricted. So most of the parameters can not be changed anymore. Exceptions are the voltage increase protection, the 10min mean value and the thresholds for f and U. All these parameters must be password protected (in addition to the seal).
Inverter: For the voltage reduction protection U <0.8UN, the delay time increases to 3 seconds to ensure that power generation systems on the low-voltage grid now also support the grid stabilization.
Technical rules for connection to the medium-voltage network
Starting with the new TAR low-voltage (VDE-AR-N 4100), a new basic regulation for this voltage level is created. From a power level Pn> 135kW, a second parameter for the frequency increase protection (so far only one) is now available. The former limit applying of the standard at> 100kW is replaced by> 135kW.
New standards in Great Britain
In the UK, the “Engineering Recommendation” G99 (> 16A) completely replaces its predecessor G59. Two sets of parameters for both Low Voltage (LV) and High Voltage (HV) will be provided. Instead of two thresholds for voltage drop protection, there is only be one left in the future. The delay time increases from 0.5s to 2.5s. With two frequency increase thresholds in the past, there is now only one set at 52Hz. “P shift” can still be activated by the operator (deactivated by default).
The “Engineering Recommendation” G98 (<16A) now completely replaces the G83 (as before only one parameter set). Instead of two thresholds for voltage drop protection, there is only one left for the future. The delay time increases from 0.5s to 2.5s. With two frequency increase thresholds in the past, only one set at 52Hz. The RoCoF (Rate of Change of Frequency) increases from 0.2Hz / sec to 1Hz / sec as in the G99.
Applications for NA003
Low voltage and medium voltage plants for:
- power generation, e.g.
- wind power
- energy distribution
- power supply