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Modbus topology
The cable must be with screen. The cable is connected from con-
troller to controller, and no branches are allowed on the cable.
If the cable length exceeds 1200 m a repeater must be inserted
One repeater must be added for every 32 controllers. If the data
communication cable runs through an electrically noisy environ-
ment which impairs the data signal, one or more repeaters must
be added to stabilise the signal.
When configuring Modbus devices on the control bus,
the highest device address that can be used is 127 (max. 120
controller in total)
The wires are looped from device to device.
A is connected to A
B is connected to B.
The screen must be connected to the system device, all controller
and any repeaters.
A screen must always be looped from device to device.
The screen must not be connected to anything else.
32
32
AK-SM
AK-SM
10
User Guide
Lit. no.
USCO.PI.R1.E1.02 © Danfoss 07-2013
AK-SM
850