2 |DKRCC.EI.RL0.I1.02 / 520H9646
© Danfoss | DCS (za) | 2015.08
Installation guide | MCX rooftop controller
110 mm - 4.33 in.
280 mm - 11.02 in.
63 mm - 2.48 in.
Dimensions:
Modbus topology:
AK-SM800:
The cable must be EIA485 rated. The cable is connected from controller 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 environment 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 124
(max 120 modbus control devices in total - max 45 MCX RTC).
The wires are looped from device to device. A is connected to A and 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.
See AK-SM800 User Guide for system 485 wiring instructions.
Manual can be found at: http://food-retail.danfoss.com/knowledge-center/software/ak-sm-800/
Be sure to configure the Modbus repeater AKA 222 (code#084B2240) to the correct baud rate.
MCX-RTU baud rate must be set to 38.4 K when used with the AK-SM800. MCX-RTU cannot be on the same 485 bus with SLVs.
Termination
Repeater
