ABB AC 800M Installation Manual

Section 1 Introduction Physical Signaling
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Physical Signaling
The BOSCH CAN specification defines two complimentary logical levels:
dominant and recessive. During simultaneous transmission of dominant and
recessive bits, the resulting bus value will be dominant. For example, in case of a
wired-AND implementation of the bus (as with DeviceNet), the dominant level
would be represented by a logical 0 and the recessive level by a logical 1. Physical
states, for example, electrical voltage that represent the logical levels are not given
in the CAN specification. The specification used for these levels is given in the
ISO 11898 standard.
For a node disconnected from the bus, the recessive (high impedance) levels for
CAN_L and CAN_H are 2.5 volts (0 volts differential). The typical dominant (low
Figure 2. EtherNet/IP and DeviceNet network embedded in 800xA

ABB AC 800M Specifications

General

Brand	ABB
Model	AC 800M
Category	Controller
Language	English