Specifications

MCB 112 output X44/12 and the signal from the safety-
related sensor are HIGH. If at least one of the 2 signals is
LOW, the output to Terminal 37 must be LOW, too. The
safety device with this AND logic itself must conform to
IEC 61508, SIL 2. The connection from the output of the
safety device with safe AND logic to Safe Torque Off
terminal 37 must be short-circuit protected. See
Illustration 2.7.
130BA967.11
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DI DI
SIL 2
Safe Stop
Digital Input
e.g. Par 5-15
PTC
Sensor
X44/
Par. 5-19
Terminal 37 Safe Stop
Safety Device
Safe Input
Safe Output
Safe AND Input
Manual Restart
PTC Thermistor Card
MCB112
Non- Hazardous AreaHazardous
Area
Illustration 2.7 Illustration of the essential aspects for
installing a combination of a Safe Torque Off application and
a MCB 112 application. The diagram shows a Restart input for
the external Safety Device. This means that in this installation
5-19 Terminal 37 Safe Stop might be set to value [7] PTC 1 &
Relay W or [8] [8] PTC 1 & Relay A/W. Refer to MCB 112
operating instructions for further details.
Parameter settings for external safety device in
combination with MCB112
If MCB 112 is connected, then additional selections ([4] PTC
1 Alarm to [9] PTC 1 & Relay W/A) become possible for
5-19 Terminal 37 Safe Stop. Selections [1] Safe Torque Off
Alarm and [3] Safe Torque Off Warning are still available but
are not to be used as these are for installations without
MCB 112 or any external safety devices. If [1] Safe Torque
Off Alarm or [3] Safe Torque Off Warning should be selected
by mistake and MCB 112 is triggered, then the frequency
converter reacts with an alarm ”Dangerous Failure [A72]”
and coasts the frequency converter safely, without
Automatic Restart. Selections [4] PTC 1 Alarm and [5] PTC 1
Warning
are not to be selected when an external safety
device is used. These selections are for when only MCB 112
uses the Safe Torque Off. If selection [4] PTC 1 Alarm or [5]
PTC 1 Warning is selected by mistake and the external
safety device triggers Safe Torque Off, the frequency
converter issues an alarm ”Dangerous Failure [A72]” and
coasts the frequency converter safely, without Automatic
Restart.
Selections [6] PTC 1 & Relay A to [9] PTC 1 & Relay W/A must
be selected for the combination of external safety device
and MCB 112.
NOTICE
Note that selections [7] PTC 1 & Relay W and [8] PTC 1 &
Relay A/W open up for Automatic restart when the
external safety device is de-activated again.
This is only allowed in the following cases:
•
The unintended restart prevention is
implemented by other parts of the Safe Torque
Off installation.
•
A presence in the dangerous zone can be
physically excluded when Safe Torque Off is not
activated. In particular, paragraph 5.3.2.5 of ISO
12100-2 2003 must be observed.
See MCB 112 operating instructions for further information.
2.6.3
Safe Torque Off Commissioning Test
After installation and before first operation, perform a
commissioning test of an installation or application making
use of Safe Torque Off.
Moreover, perform the test after each modification of the
installation or application, which the Safe Torque Off is
part of.
NOTICE
A passed commissioning test is mandatory after first
installation and after each change to the safety instal-
lation.
The commissioning test (select one of cases 1 or 2 as
applicable):
Case 1: Restart prevention for Safe Torque Off is
required (i.e. Safe Torque Off only where 5-19 Terminal
37 Safe Stop is set to default value [1], or combined Safe
Torque Off and MCB112 where 5-19 Terminal 37 Safe
Stop is set to [6] or [9]):
1.1 Remove the 24 V DC voltage supply to
terminal 37 by the interrupt device while the
motor is driven by the FC 102 (i.e. mains supply is
not interrupted). The test step is passed if the
motor reacts with a coast and the mechanical
brake (if connected) is activated, and if an LCP is
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