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Installation and Operational Instructions for
ROBA
®
-brake-checker plus AC Type 029.700.2
(B.0297002.EN)
your reliable partner
26/06/2019 HH/GF
Page 8 of 10
Chr. Mayr GmbH + Co. KG
Eichenstraße 1, D-87665 Mauerstetten, Germany
Tel.: +49 8341 804-0, Fax: +49 8341 804-421
www.mayr.com
, E-Mail:
88
Intended Use
ROBA
®
-brake-checker products have been developed,
manufactured and tested as electronic equipment in
compliance with the DIN EN 50178 standard and in
accordance with the EU Low Voltage Directive. During
installation, operation and maintenance of the product, the
requirements for the standard must be observed. ROBA
®
-
brake-checker products are for use in machines, systems
and devices and must only be used in the situations for
which they are ordered and confirmed. The products are
designed for installation into electrical control cabinets and
terminal boxes. Using them for any other purpose is not
allowed.
Basically:
Apply supply voltage 24 VDC (control terminal) before
switching input voltage VAC (power terminal). Otherwise an
error can occur.
Coil Capacity
If the switching frequency is higher than
1 cycle per minute or if the overexcitation
time t
O
is longer than double the separation
time t
2
, please observe the following:
P ≤ P
N
The coil capacity P must not be larger than
P
N
or the nominal current I
RMS
which flows
through the ROBA
®
-brake-checker must not
be exceeded, as otherwise the coil and the
ROBA
®
-brake-checker can fail due to ther-
mal overload.
At high input voltage and low brake perfor-
mance, the initial bridge rectification of 50
ms can lead to thermic overload.
Calculations:
P
[W] RMS coil capacity dependent on switching fre-
quency, overexcitation, reduction in capacity
and duty cycle
P
=
P
O
x t
O
+ P
H
x t
H
T
P
N
[W] Coil nominal capacity (catalogue values, Type
tag)
P
O
[W] Coil capacity on overexcitation
P
O
=
(
U
O
)²
x P
N
U
N
P
H
[W] Coil capacity at reduced capacity
P
H
=
(
U
H
)²
x P
N
U
N
t
O
[s] Overexcitation time
t
H
[s] Time of operation with reduction in capacity
t
off
[s] Time without voltage
t
on
[s] Time with voltage
T [s] Total time (t
O
+ t
H
+ t
off
)
U
O
[V] Overexcitation voltage (bridge voltage)
U
H
[V] Holding voltage (half-wave voltage)
U
N
[V] Coil nominal voltage
I
RMS
[A] RMS current dependent on switching frequen-
cy, overexcitation time and duty cycle
I
RMS
=
P x P
N
U
N
²
Time Diagram:
T
t
on
t
off
t
O
t
H
U
U
O
U
N
U
H
t
Protection circuit
When using DC-side switching, the coil
must be protected by a suitable protection
circuit according to VDE 0580, which is inte-
grated in
mayr
®
monitoring modules. Never-
theless, the high switch-off voltage produc-
es switching sparks, which lead to contact
consumption.
Therefore, only use the main contacts of a
contactor suitable for inductive loads with
a minimum contact opening of 3 mm for
switching the DC-side contact S
DC
. Series
connection of main contacts reduces wear.
88
