ABB ACH550-UH User Manual

1-188 ACH550-UH User’s Manual
Embedded fieldbus
Preferred wiring diagram
Alternate wiring diagram
NOTES:
ON
ON
O
N
28
29 30
31 3
2
SCR Screen B + Positive A - Negative AGND SCR Screen
SeeNote2
:
Shield
S
e
e
No
te
2
ACH55
0 RS485:
T
er
minal
Block-X1
Building Automation
Contr
o
ller
G
-
+
R
See Note 3: G
rou
nd
SeeNote4: Re
ference/
Common
Requi
r
e
dWiring:
ANSI/ASHRAE Standa
rd 135
(Tw
i
sted Pair and Re
f
erence
with Iso
l
ated Devices)
See
No
te 6
1. Us
e
3C
o
nduct
o
rCable-1twistedtrip
l
et.
T
ie 3rd
wire to AGND: X1-31.
2. Tie shield wires together at Drive - Do Not terminate
at SCR.
3. Terminate shield ONLY at "Ground" terminal in the
Building Automation Controller.
4. Terminate AGND wire at "Reference" terminal in the
Building Automation Controller.
5. SetswitchJ2toOFF. BUSterminationisanactive
network: Pull Up & Pull Down (BIAS) resistors are
on board the ACH550 Drive.
6. NOTE: the transceiver in the ACH550 is a full load
device. Only 31 ACH550 drives may be connected
to a given EIA-485 segment without repeaters.

ABB ACH550-UH Specifications

General

Brand	ABB
Model	ACH550-UH
Category	Controller
Language	English