Safe Torque Off (Sto) - Danfoss VLT AutomationDrive FC 302 Installation Manual

Electrical Installation
Long control cables and analog signals may result in 50/60
Hz ground loops due to noise from line power supply
cables.
If ground loops occur, break the shield or insert a 100 nF
capacitor between shield and chassis, if needed.
4 4
Connect the digital and analog inputs and outputs to the
control cards of the units separately to avoid ground
currents. These connections are on terminals 20, 55, and 39
for both the filter and adjustable frequency drive sections.
12 13
Figure 4.14 Input Polarity of Control Terminals, PNP
12 13
Figure 4.15 Input Polarity of Control Terminals, NPN
46
PNP (Source)
Digital input wiring
18 19 27 29 32 33
NPN (Sink)
Digital input wiring
18 19 27 29 32 33
Danfoss A/S © Rev. 04/2015 All rights reserved.
®
VLT AutomationDrive FC 302 Low Harmonic Drive
132–630 kW
NOTICE!
To comply with EMC emission specifications, shielded/
armored cables are recommended. If using non-shielded/
armored cable, see chapter 4.7.3 Power and Control Wiring
for Non-shielded Cables. If using non-shielded control
cables, use ferrite cores to improve EMC performance.
20 37
1
Figure 4.16 Connecting Shielded Cables
20 37 Connect the shields in a proper way to ensure optimum
electrical immunity.

4.8.5 Safe Torque Off (STO)

To run STO, additional wiring for the frequency converter is
required. Refer to VLT
Operating Instructions for further information.
2
®
Frequency Converters Safe Torque Off
MG37A322