NOTE
For all applications with Safe Stop it is important that short
circuit in the wiring to T37 can be excluded. Exclude the
short circuit as described in EN ISO 13849-2 D4 by the use
of protected wiring, (shielded or segregated).
130BC972.10
12
37
1
3
4
2
Illustration 4.25 STO Example
1
Frequency converter
2
[Reset] key
3
Safety relay
4
Emergency stop
Table 4.29 Legend
Example with SS1
SS1 correspond to a controlled stop, stop category 1
according to IEC 60204-1 (see
). When
activating the safety function the frequency converter
performs a normal controlled stop. This can be activated
through terminal 27. After the safe delay time has expired
on the external safety module, the STO will be triggered
and terminal 37 will be set low. Ramping down as
configured in the frequency converter. If the frequency
converter is not stopped after the safe delay time, the
activation of STO will coast the frequency converter.
NOTE
When using the SS1 function, the brake ramp of the
frequency converter is not monitored with respect to
safety.
130BC973.10
18
37
4
1
2
12
3
Illustration 4.26 SS1 Example
1
Frequency converter
2
[Reset] key
3
Safety relay
4
Emergency stop
Table 4.30 Legend
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,
implement one channel via Safe Stop T37 (STO) and the
other by a contactor. Connect the contactor in either the
frequency converter input or output power circuits and
controlled by the Safety relay (see
). The
contactor must be monitored through an auxiliary guided
contact, and connected to the reset input of the Safety
Relay.
Application Examples
VLT
®
Decentral Drive FCD 302
70
MG04H102 - VLT
®
is a registered Danfoss trademark
4
4