Illustration 5.16: Terminal 37: Safe Stop Input Available With Safe Stop Function Only - Danfoss VLT Series Design Manual

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VLT HVAC Drive Design Guide
5.2.12. Electrical Installation, Control Cables

Illustration 5.16: Terminal 37: Safe Stop input available with Safe Stop Function only!

Very long control cables and analog signals may in rare cases and depending on installation result
in 50/60 Hz earth loops due to noise from mains supply cables.
If this occurs, you may have to break the screen or insert a 100 nF capacitor between screen and
chassis.
The digital and analog in- and outputs must be connected separately to the VLT HVAC Drive
common inputs (terminal 20, 55, 39) to avoid ground currents from both groups to affect other
groups. For example, switching on the digital input may disturb the analog input signal.
NB!
Control cables must be screened/armoured.
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MG.11.B2.02 - VLT is a registered Danfoss trademark
5. How to Install
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