Page 137 - dehn-catalogue-safety-equipment_0

DEHNcare ® APC, APJ, APT DEHNcare ® APG DEHNcare ® APHO DEHNcare ® ESH U S, APS Arc Fault Protection System Water Jet Protection
Active Arc Fault Protection

DEHNshort – Active Arc Fault Protection System
• Protection of persons and installations and function in accor-
dance with DIN EN 61439-2, Suppl. 1 (IEC/TR 61641 ed. 3, 2014)
• Maximum availability of installations
• Modular system design
• System status is indicated at the front of the installation
General Information:
DSRT QD: 400 V AC;
Rated operating voltage (Ue)
DSRT QD II: 690 V AC
Rated short-time withstand current of the DSRT QD: 80 kA, 50 ms;
quenching devices (Icw) DSRT QD II: 110 kA, 300 ms
Lower response threshold (Iparc) 5 kA
Max. admissible ambient temperature of –20 °C ... +85 °C
the point sensors (during operation)
Max. admissible ambient temperature of –5 °C ... +85 °C DEHNshort – active arc fault protection system
the fibre-optic sensors (during operation)
Max. admissible ambient temperature of –5 °C ... +70 °C
the quenching devices (during operation)
DSRT QD: < 2-3 ms at 80 kA;
Typical arc fault extinction times (tb)
DSRT QD II: < 3-4 ms at 100 kA
DEHNshort optimally protects persons and switchgear installations from Quenching
the effects of an arc fault. To achieve this, particularly short response times As soon as the quenching devices are activated, a bolted short-circuit is
are required in high-energy switchgear installations. Just a few millisec- generated in parallel to the arc fault within a short period of time. Due to
onds are decisive for the intensity and the effects of an arc fault. this low-impedance bypass, the voltage drops and the arc fault is
DEHNshort detects the arc fault the moment it starts to develop, evaluates quenched immediately. Thyristors short-circuit the three phases of the
the detected sensor signals and quenches the arc fault by generating a busbar directly after the quenching devices have been activated.
three-phase bolted short-circuit. Subsequently, a spring-driven contact system carries the short-circuit cur-
rent until the installation is disconnected by the feeder circuit breakers.
Functional principle:
Detection Isolation
The protection transformers situated upstream of the feeder circuit break- To ensure that the switchgear installation is not loaded with the short-cir-
ers detect the overcurrent resulting from the arc fault in all infeeds. Special cuit current for longer than necessary – and to ensure additional safety
light sensors detect the extremely bright light of the arc fault. Depending – a disconnection command is transmitted to the relevant shunt release
on the requirements of the relevant switchgear installation, light sensors of all feeder circuit breakers via floating contacts. This means that the
are available as point sensors or fibre optic sensors. busbar section where the arc fault occurred is already isolated from the
system. Active Arc Fault Protection
Evaluation
Electronic detection devices link the sensor signals and activate the Re-commissioning
quenching devices of the relevant busbar as well as the shunt releases of The switchgear installation can be immediately re-commissioned after the
all feeder circuit breakers in case of both detection parameters. fault has been rectified, the quenching devices have been replaced and
an isolation test has been carried out. The arc fault protection system
significantly exceeds the requirements of test criteria 1-7 of IEC TR 61641
ed3 of 2014. DEHNshort is used wherever the protection of persons and
availability of the power supply is vital.

supply from transformer
UPS: Uninterruptible power supply
L1-L3: Busbar
detection device
UPS
DEHNshort
POWER
ERROR
T1 T3
T2 T4
S1 IL1
S2 IL2
S3 IL3
S4 Io
QD BI1
Built-in protection transformers Built-in light sensors circuit Trip BI2 BO1 SET HSO2 HSO1
breaker DSRT DD CPS ....
ARC PROTECTION
optoelectric
sensor DSRT PS DEHN
L1
Quenching Device fibre
optoelectric Störlichtbogenlöschgeräteinheit optic
Quenching Device
sensor DEHN DSRT PS cable
L2
Quenching Device
optoelectric Störlichtbogenlöschgeräteinheit
Quenching Device
sensor DEHN DSRT PS
L3
Detection devices integrated in Quenching device above the sup- Basic circuit diagram
the door ply switch
Valid as of January 1, 2019 You will find detailed product information on our website 135