Woodward LS-5 v2 Series - Page 114

genset control. A more detailed description relating to that VDE rule is done through the
separated application note "DE37671 easYgen-3000_LS5_VDE-AR-N 4105" on the manual
CD of this product.
Here are some functions which have to be covered according to the VDE-AR-N 4105 rule:
• The mains decoupling is executed through following monitors:
◦ Mains under voltage V<
◦
Mains over voltage V>
◦
Mains under frequency f<
◦ Mains over frequency f>
◦ Mains voltage increase
• Recognizing isolation operation (other decoupling argument)
◦ Phase shift OR
◦ df/dt
• Button for Testing the Decoupling Facility
•
Single-failure-security including self-monitoring
The VDE-AR-N 4105 demands a Single-failure-proof of the mains decoupling function. That
means that the decoupling of the generator from the mains must be always ensured,
even if a single element in the system fails. So the system must contain two circuit
breakers with two independent monitoring functions acting individually on each breaker.
From the perspective of the network provider that rule pursuits the mains protection but
not the availability of the electrical source, so in case of doubt the generator should be
decoupled from mains.
Woodward solves this requirement with the use of a minimum of two devices acting as a
system (for example two LS-5 or an easYgen with VDE-AR-N 4105 functionality and an
LS-5). The system allows incorporating more devices, so that the availability of the
generator can still be increased.
The demanded two breakers in series are realized by the use of a GCB and an MCB. If
only a GCB is available, the customer must install another circuit breaker in addition. If a
breaker with LS-5 is installed between GCB and mains, the LS-5 can take over the part of
the second device acting on the MCB. It also is allowed to use 2 LS-5 devices in series
acting on two breakers, so the easYgen with its GCB would not be incorporated. This
depends on the application for sure. Please refer to chapter ╚═▷ “6.1 Application Modes
Overview” for more information.
An important item of the VDE-AR-N 4105 is the Single-Failure-Diagnostic, at which a
minimum of two devices exchange their measurement data and settings via
communication interface (usually CANbus). This allows to determine whether the Single-
Failure-Proof is lost and the device can issue an alarm.
Diagnostic via CAN interface
Devices with 4105 diagnostic check following items mutually:
114 LS-5 v2 Series 37650
4 Con󰈡guration
4.3 Con󰈡gure Monitoring
Released