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Innovative products for PV systems

DEHNguard M YPV SCI: Type 2 arrester with SCI DEHNventil and DEHNshield : Type 1 spark-gap-
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®
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technology for maximum safety and fire protection based arresters for directly protecting the inverter
The proven technique of the fault-resistant Y circuit and of Only spark-gap-based combined lightning current and surge
the combined disconnection and short-circuiting device with arresters such as DEHNventil or DEHNshield combine light-
Thermo Dynamic Control is supplemented by an additional ning equipotential bonding and protection of the inverter in
d.c. fuse. Switching stages: a single device.
1. 2. 3.
Original state Response of the Arc extinction Safe electrical The voltage switching characteristic of the spark gap acts
disconnection device isolation
like a wave breaker, reducing the energy of the lightning
current to an acceptable level. The spark gap absorbs almost
the entire energy, thus hardly stressing the inverter.

Varistor-based type 1 arresters, in contrast, do not have a
voltage switching, but a voltage limiting characteristic. As a
consequence, the use of these arresters must be considered
SCI SCI SCI SCI and calculated in detail. The requirements of higher classes
of LPS can only be fulfilled to a limited extent.
The figure shows the switching phases of the three-step d.c.
switching device in the DEHNguard M YPV SCI. DEHNventil and DEHNshield spark-gap-based type 1
arresters protect the inverter and thus the heart of the PV
The fuse particularly dimensioned for PV systems in the system.
short-circuit path was integrated to ensure disconnection at
any time. This allows to replace an overloaded protection
module without special tools – in a de-energised state and
without arcing.

DEHNguard M Y PV SCI type 2 arresters with integrated d.c.
fuse combine efficient surge protection with personnel and
fire protection.

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