In rare cases, very long control cables and analog signals
may, depending on installation, result in 50/60 Hz ground
loops due to noise from line power supply cables.
If this occurs, it may be necessary to break the shield or
insert a 100 nF capacitor between shield and chassis.
The digital and analog inputs and outputs must be
connected separately to the adjustable frequency 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.
Input polarity of control terminals
12
13
18
19
27
29
32
33
20
37
+24
V DC
0
VDC
130
BT106.10
PNP (Source)
Digital input wiring
NPN (Sink)
Digital input wiring
12
13
18
19
27
29
32
33
20
37
+24
V DC
0
VDC
130
BT107.11
NOTE!
Control cables must be shielded/armored.
130B
T340.10
Connect the wires as described in the Instruction Manual
for the adjustable frequency drive. Remember to connect
the shields in a proper way to ensure optimum electrical
immunity.
How to Install
VLT AQUA 12-Pulse High Power Instruction Manual
MG.20.Y1.22 - VLT
®
is a registered Danfoss trademark
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