Installation and operational instructions for
ROBA
®
-servostop
®
Type 8980.00_00
Sizes 50 - 160
(B.8980.EN)
06/10/2022 GF
Chr. Mayr GmbH + Co. KG
Eichenstraße 1, D-87665 Mauerstetten
Phone: +49 8341 804-0, Fax: +49 8341 804-421
Page 20 of 26
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7.4.2.2 DC-side switching
Supply with DC voltage
The power circuit is interrupted between the power supply
and the coil. The magnetic field is quickly reduced via the
protective element. This causes a quick rise in braking
torque and a quick connection time t
1
. The varistor is to
be dimensioned in accordance with the maximum
occurring DC or AC voltage. The recommended disk
diameters are 14
– 20 mm.
When switching DC-side, high voltage peaks are
produced in the coil. This can lead to wear on the
switching contacts from sparks and to destruction of the
insulation. For this reason, the voltage peaks must be
limited (see section
DC-side switching causes the
shortest connection
times on the brake (e.g. for EMERGENCY STOP
operation or for safety switch-offs)
so that the braking
torque is made available as quickly as possible for short
braking distances or for fast take-over of loads.
Please Observe!
Safety switch-off
In applications with a necessarily short
switching time for short braking distances
and fast take-over of loads, reliable DC-
side switch-off is required e.g. through
redundant, monitored contactors.
(see schematic wiring diagram 3)
7.5
Protection Circuit
When using DC-side switching, the coil must be protected
by a suitable protection circuit according to VDE 0580,
which is integrated in
mayr
®
-supply and monitoring
modules. To protect the switching contact from
consumption when using DC-side switching, additional
protective measures are necessary (e.g. series
connection of switching contacts). The switching contacts
used should have a minimum contact opening of 3 mm
and should be suitable for inductive load switching.
Please make sure on selection that the rated voltage and
the rated operating current are sufficient.
Depending on the application, the switching contact can
also be protected by other protection circuits (e.g.
mayr
®
-
spark quenching unit), although this may of course then
alter the switching times.
The following parameters can be changed through
suitable adaptations of the protection circuit.
Contact lifetime
Switching times on drop-out
Voltage peaks or level of switch-off voltage
Please contact mayr
®
power transmission.
Please Observe!
For accessories, please go to
8
Storage
8.1.1
Brake Storage
Store the brakes in a horizontal position, in dry
rooms and dust and vibration-free.
Relative air humidity < 50 %.
Temperature without major fluctuations within a
range from 20 °C up to +40 °C.
Do not store in direct sunlight or UV light.
Do not store aggressive, corrosive substances
(solvents / acids / lyes / salts etc.) near to the
brakes.
For longer storage lasting more than 2 years, special
measures are required.
► Please contact mayr
®
power transmission.
Storage acc. DIN EN 60721-3-1 (including the limitations
/ additions described above): 1K3; 1Z1; 1B1; 1C2; 1S3;
1M1
U
L+
L-
Schematic wiring diagram 2
Schematic wiring diagram 3
U
L+
L-
