User Manual
Page 13
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
ea1974@elektroautomatik.de
ENS2
1.8 Construction and function
1.8.1 General description
The module ENS2 is a separately installed, integrated grid protection equipment, also called automatic isolation
unit(AIU),designedtomeetgermanstandardVDE-AR-N4105.Thespecicationsofthatstandardaresuitablefor
most european countries running three-phase supplies 400V (L-L) resp. 230V (L-N). The AIU is intended to cut the
connection between a power generating or energy recovering device (here: electronic load with energy recovery
feature) and the public AC supply grid on distortions regarding voltage or frequency, by means of controlling two
serial contactors (with or without feedback contact).
Theinternalsupervisioncircuitmonitorsthethreephasesofthepublicgridfoructuationsofvoltageandfrequency.
Incasecertainsupervisionthresholds,asdenedbythestandard,areexceededitwillcutthepowergeneration
devicefromthepublicgridbymeansoftwobreakers(contactors,twopiecesforsafetyof100%cuttingo).
When operating electronic loads with energy recovery feature, such as of series ELR 9000, ELR 9000 HP, ELR
10000, or recuperating power supplies such as PSB 9000 and PSB 10000, this kind of supervision equipment is not
necessarilyrequired,unlessthedeviceisrunninginaso-called“isolatedoperation”.Isolatedoperationitmeans,
that the device is supplying energy back to the grid (local or public), but there are no consumers in proximity which
partly or fully consume the energy.
TheabovementionedVDEstandardonlydenestheparametersforoperationofthisequipmentinGermany.
Whetherthegermanstandardmeetsspecicationsindierentcountriescannotbedeterminedbythemanufac-
turer of the equipment, but the end user. In case of doubt it must be found out whether it’s required to install grid
protection equipment to allow operation of such a recuperating device. It’s supposed that other european countries
have similar standards and/or provisions for this type of equipment and its operation.
• This grid protection equipment is not suitable for 60 Hz grids!
• Thisgridprotectionequipmentonlyworkson400Vresp.230Vsupplyvoltage”
1.8.2 Factory settings of german standard VDE-AR-N 4105
The ENS2 is delivered with following default parameters, which can also work in most european countries running
230V mains voltage for single phase and 400V for three-phase:
Cut-o delays
Supervision parameter Limit Delay
Undervoltage N-L 184V 100ms
Overvoltage N-L (10 minute average) 253V 10min
Overvoltage N-L 264,5V 100ms
Undervoltage L-L 320 V 100ms
Overvoltage L-L (10 minute average) 440V 10mins
Overvoltage L-L 460V 100ms
Low frequency 47.5Hz 100ms
High frequency 51.5Hz 100ms
Switch-on delays
Supervision parameter Limit
Switch-on delay
(normal) *
Switch-on delay
(short-term interruption) **
Undervoltage N-L 195.5V 60s 5s
Overvoltage N-L 253V 60s 5s
Undervoltage L-L 340V 60s 5s
Overvoltage L-L 440V 60s 5s
Low frequency 47.5Hz 60s 5s
High frequency 50.05Hz 60s 5s
* Within the time of switch-on delay, supervised values must remain within the limits
** A short-term interruption of the supply, according to VDE-AR-N 4105, is less than a maximum of 3 seconds