BACnet MS/TP—On-Board Communication
Prepare for Use through MS/TP
1.
Open the cover of the AC drive.
WARNING
The relay outputs and other I/O-terminals may have a
dangerous control voltage present even when G-Max is
disconnected from mains.
2.
Locate the components that you will need on the drive
to connect and run the BACnet cables.
3.
Strip about 0.59 in (15 mm) of the RS-485 cable and cut
off the grey cable shield. Remember to do this for both
bus cables (except for the last device). Leave no more
than 0.39 in (10 mm) of the cable outside the terminal
block and strip the cables at about 0.20 in (5 mm) to fit in
the terminals. See illustration below.
Figure 29. Stripping the Cable
Also strip the cable now at such a distance from the terminal
that you can fix it to the frame with the grounding clamp.
Strip the cable at a maximum length of 0.59 in (15 mm).
IMPORTANT
!
Do not strip the aluminum cable shield!
Figure 30. RS-485 Cable Strip (Aluminum Shield)
4.
Then connect the cable to its appropriate terminals on
G-Max drive standard terminal block, terminals A and B
(A = negative, B = positive). See illustration below.
70
PowerXL DG1 Series VFD MN040010EN—May 2014 www.eaton.com
Figure 31. G-Max Drive Terminals (BACnet)
5.
Using the cable clamp included in the delivery of the
drive, ground the shield of the RS-485 cable to the frame
of the AC drive.
Figure 32. RS-485 Ground
6.
If G-Max is the last device on the bus, the bus
termination must be set. Locate the DIP switches to the
right of the control keypad of the drive and turn the
switch for the RS-485 bus termination resistor to
position ON. Biasing is built in the termination resistor.
See also step 8 below.