50/60 Hz earth (ground) loops
With very long control cables, earth loops (ground loops)
may occur. To eliminate earth (ground) loops, connect one
end of the screen-to-earth (ground) with a 100 nF
capacitor (keeping leads short).
100nF
FC
PE
PE
PLC
130BB609.11
Illustration 2.14
Avoid EMC noise on serial communication
This terminal is connected to earth (ground) via an internal
RC link. Use twisted-pair cables to reduce interference
between conductors. The recommended method is shown
below:
PE
FC
PE
FC
130BB923.11
PE
PE
69
68
61
69
68
61
1
2
Illustration 2.15
Alternatively, the connection to terminal 61 can be
omitted:
PE
FC
PE
FC
130BB924.11
PE
PE
69
69
68
68
1
2
Illustration 2.16
2.5.4 Control Terminal Types
Terminal functions and default settings are summarized in
2.5.6 Control Terminal Functions
.
1
4
2
3
130BA012.11
61
68
69
39
42
50
53
54
55
12
13
18
19
27
29
32
33
20
37
Illustration 2.17 Control Terminal Locations
•
Connector 1 provides four programmable digital
input terminals, two additional digital terminals
programmable as either input or output, a 24 V
DC terminal supply voltage, and a common for
optional customer supplied 24 V DC voltage.
•
Connector 2 terminals (+)68 and (-)69 are for an
RS-485 serial communications connection.
•
Connector 3 provides two analog inputs, one
analog output, 10 V DC supply voltage, and
commons for the inputs and output.
•
Connector 4 is a USB port available for use with
the MCT 10 Set-up Software.
•
Also provided are two Form C relay outputs that
are in various locations depending upon the
frequency converter configuration and size.
•
Some options available for ordering with the unit
may provide additional terminals. See the manual
provided with the equipment option.
2.5.5 Wiring to Control Terminals
Terminal plugs can be removed for easy access.
Installation
VLT
®
HVAC Drive D-Frame
Operating Instructions
MG16D102 - VLT
®
is a registered Danfoss trademark
17
2
2
