Analog Input Terminals; Digital Inputs; Digital Outputs; General - Delta VFD-B Series Manual

Analog input terminals (AVI, ACI, AUI, ACM)
Analog input signals are easily affected by external noise. Use shielded wiring and keep it as short
as possible (<20m) with proper grounding. If the noise is inductive, connecting the shield to terminal
ACM can bring improvement.
If the analog input signals are affected by noise from the AC motor drive, please connect a capacitor
and ferrite core as indicated in the following diagrams:
Digital inputs (FWD, REV, JOG, EF, TRG, MI1~MI6, DCM)
When using contacts or switches to control the digital inputs, please use high quality components to
avoid contact bounce.
Digital outputs (MO1, MO2, MO3, MCM)
Make sure to connect the digital outputs to the right polarity, see wiring diagrams.
When connecting a relay to the digital outputs, connect a surge absorber or fly-back diode across
the coil and check the polarity.

General

Keep control wiring as far as possible from the power wiring and in separate conduits to avoid
interference. If necessary let them cross only at 90º angle.
The AC motor drive control wiring should be properly installed and not touch any live power wiring or
terminals.
Revision 10/2005, BE13, SW V4.08
C
ferrite core
wind each wires 3 times or more around the core
Chapter 2 Installation and Wiring VFD-B Series
AVI/ACI/AUI
ACM
2-25