Danfoss VLT FC 102 Series Design Manual page 20

Introduction to VLT® HVAC D...
2 2
Figure 2.1 Jumper between Terminal 12/13 (24 V) and 37
Figure 2.2 Installation to Achieve a Stopping Category 0
(EN 60204-1) with Safety Cat. 3/PL "d" (ISO 13849-1) or
SIL 2 (EN 62061).
1 Safety relay (cat. 3, PL d or SIL2
2 Emergency stop button
3 Reset button
4 Short-circuit protected cable (if not inside installation
IP54 cabinet)
Table 2.3 Legend to Figure 2.2
18
Design Guide
FC
3
12
1
37
4
2
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Safe Torque Off Commissioning Test
After installation and before first operation, perform a
commissioning test of the installation making use of Safe
Torque Off. Also, perform the test after each modification
of the installation.
Example with STO
A safety relay evaluates the E-Stop button signals and
triggers an STO function on the adjustable frequency drive
in the event of an activation of the E-Stop button (See
Figure 2.3). This safety function corresponds to a category 0
stop (uncontrolled stop) in accordance with IEC 60204-1. If
the function is triggered during operation, the motor runs
down in an uncontrolled manner. The power to the motor
is safely removed, so that no further movement is possible.
It is not necessary to monitor plant at a standstill. If an
external force effect is to be anticipated, provide additional
measures to safely prevent any potential movement
(e.g., mechanical brakes).
NOTICE!
For all applications with Safe Torque Off, it is important
that short circuit in the wiring to T37 can be excluded.
This can be done as described in EN ISO 13849-2 D4 by
the use of protected wiring, (shielded or segregated).
Example with SS1
SS1 correspond to a controlled stop, stop category 1
according to IEC 60204-1 (see Figure 2.4). When activating
the safety function, a normal controlled stop is performed.
This can be activated through terminal 27. After the safe
delay time has expired on the external safety module, the
STO is triggered and terminal 37 is set low. Ramp-down is
performed as configured in the adjustable frequency drive.
If the adjustable frequency drive is not stopped after the
safe delay time, the activation of STO coasts the adjustable
frequency drive.
NOTICE!
When using the SS1 function, the brake ramp of the
adjustable frequency drive is not monitored with respect
to safety.
Example with Category 4/PL e application
Where the safety control system design requires two
channels for the STO function to achieve Category 4/PL e,
one channel can be implemented by Safe Torque Off T37
(STO) and the other by a contactor which may be
connected in either the adjustable frequency drive input or
output power circuits and controlled by the safety relay
(see Figure 2.5). The contactor must be monitored through
an auxiliary guided contact and connected to the reset
input of the safety relay.
MG11BC22