Vacon OPTAF, User Manual

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vacon • 28 STO AND SS1 SAFETY FUNCTIONS
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
3.5 Commissioning
NOTE! The use of STO, SS1 or other safety functions does not itself ensure safety. Always make sure
that the safety of the entire system is confirmed. See also the warnings on page 14.
The OPTAF option board has an overvoltage protection that can activate due to fast transients when
connecting the +24 V. The activation causes the +24 V input to be short-circuited. It is essential to
protect the drive and the supply with a fuse placed on the supply line according to the instructions
in the drive operating guide. See, for example, VACON
®
NXS/NXP Air-cooled Wall-mounted and
Standalone Operating Guide. Do not use fuses with higher current rating. If the behavior reoccurs
after replacing the fuse, contact Danfoss for technical support.
3.5.1 General wiring instructions
• The wiring should be done according to the general wiring instructions for the specific prod-
uct where OPTAF is installed. See wiring examples in the Figure 12, Figure 13 and Figure 14.
• If shielded cable is used, the shield must be connected to the drive's lid (PE) using a ground-
ing clamp.
• EN 60204-1 part 13.5: The voltage drop from supply point to load must not exceed 5%.
• In practice, due to electromagnetic disturbances, the cable length should be limited to max.
200 m when using shielded cable and to max. 50 m when using unshielded cable. In a noisy
environment, the length of the cable could still be less in order to avoid unwanted tripping.
• Using unshielded cables is not allowed with some STO input configurations. Also some STO
input connection options are not allowed to be used with certain safety actuator types. See
Table 6 for details.
• The +24V power supply used for safety actuators may come from control board (e.g. drive's
control connector pins 6 & 7) or it may also be external, earth fault and short circuit pro-
tected power supply.
Figure 12. STO connection example 1
SAFETY ACTUATOR
OPTAF
CHANNEL 1
SW P
+24V
OV
SW M
SD1+
SD1-
OPTAF
CHANNEL 2
SD2+
SD2-
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