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ACH550-UH User’s Manual
Serial Communication – EFB
and
REF
2). Note, fieldbus references are bipolar, that is they can be positive or
negative.
N2 Protocol Technical Data
Overview
The N2 Fieldbus connection to the ACH550 drives is based on an industry standard
RS-485 physical interface. The N2 Fieldbus protocol is a master-slave type, serial
communication protocol, used by the Johnson Controls Metasys® system. In the
Metasys architecture the N2 Fieldbus connects object interfaces and remote
controllers to Network Control Units (NCUs).
The N2 Fieldbus can also be used to connect ACH550 drives to the Metasys
Companion product line.
This section describes the use of the N2 Fieldbus with the ACH550 drives’
connection and does not describe the protocol in detail.
ABB Drives Profile
Parameter
Value Setting
AI Reference Scaling
1003
DIRECTION
1 (
FORWARD
)
1003
DIRECTION
2 (
REVERSE
)
1003
DIRECTION
3 (
REQUEST
)
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference