User`s manual

136 Serial communications
ACH550-01 User's Manual
Embedded fieldbus (EFB)
To reduce noise on the network, terminate the RS485 network
using 120 ohm resistors at both ends of the network. See the
diagram below.
Use preferably three conductors and a shield for the connection.
Setting up communication through EFB
Before configuring the drive for fieldbus control, the drive must
be connected to the fieldbus according to the instructions given
in this manual and manuals Embedded Fieldbus (EFB) Control
Terminated
station
Terminated
station Station Station
e 3 Conductor Cable - Tie 3rd Wire to AGND: X1-31.
S:
28
29 30 31 32
SCR Screen B + Positive A - Negative AGND SCR Screen
See Note 3: Shield
See Note 2
ACH 550 RS485:
Terminal Block -X1
Building Automation
Controller
G
-
+
R
See Note 4: Ground
minate shield ONLY at "Ground" terminal
he Building Automation Controller!
minate AGN wire at "Reference" terminal
he Building Automation Controller!
t switch J2 to OFF. BUS termination is an active network:
l Up & Pull Down (BIAS) resistors are on board the ACH550 Drive!
shield wires together at Drive -
Not terminate at SCR!
See Note 5: Reference/Common
PREFERRED WIRING:
3 Conductor with Shield
Notes:
1. Set switch J2 to OFF. ON position would make
the network active (pull up & pull down [BIAS]
resistors are on board the drive).
2. Tie shield wires together at the drive – Do
NOT terminate at SCR.
3. Terminate shield ONLY at the “Ground”
terminal in the building automation controller.
4. Terminate AGND wire at the “Reference”
terminal in the building automation controller.
See
Note 1
SCR Screen SCR Screen B + Positive A - Negative AGND
ACH550 RS485:
Terminal block X1
Building automation
controller
See Note 4: Reference/
Common
See Note 3:
Ground
See Note 2: Shield