Connection; Connect To The Ac Indoor Unit; Connection To The Eia-485 Bus - IntesisBox ME-AC-MBS-1 User Manual

2. Connection

The interface comes with a specific cable and connectors to establish direct connection with the
AC indoor unit. It comes as well with a plug-in terminal block of 2 poles to establish direct
connection with the Modbus RTU EIA-485 network.

2.1 Connect to the AC indoor unit

To connect the ME-AC-MBS-1 interface with the AC indoor unit you must follow these steps:
Disconnect Mains Power from the AC unit. Open the front cover of the indoor unit to have
access to the electronic circuit. Once you arrive at the electronic circuit, locate the socket
connector marked as CN105.
Take the cable that comes with the interface, insert one of its connectors (the one installed in
the shortest uncovered part) into the socket of the ME-AC-MBS-1, and the other connector (the
one installed in the largest uncovered part) to the socket CN105 of the AC unit's electronic
circuit. You can place the ME-AC-MBS-1 inside or outside the AC indoor unit depending on your
needs. Remember that the ME-AC-MBS-1 must also be connected to the Modbus RTU EIA-485
network. Close the AC indoor unit's front cover again to finish the connection.
Do not modify the length of the cable supplied with the interface, it may affect the correct
interface's operation.
CN105
Electronic control board

2.2 Connection to the EIA-485 bus

Connect the EIA-485 bus wires to the plug-in terminal block of ME-AC-MBS-1 (the one with two
poles) and keep the polarity on this connection (A+ and B-). Make sure that the maximum
distance to the bus is 1,200 meters (3,937 ft). Loop or star typologies are not allowed in the
case of the EIA-485 bus. A terminator resistor of 120Ω must be present at each end of the bus
to avoid signal reflections. The bus needs a fail-safe biasing mechanism (see section 4.6 for
more details).
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox ® is a registered trademark of Intesis Software SLU
ME-AC-MBS-1
AC indoor unit
200 mm / 7.9"
For
Fixing screw
extract the upper and
lower
you listen the "click".
Connection cable
provided with the
interface
40 mm / 1.6"
AC Unit
IntesisBox
wall mounting,
staples until
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Phone
User's Manual r21 EN
Use this hole to
attach the cable
using the staple
and the screw
provided with the
interface
53 mm / 2.1"
®
90 mm / 3.5"
ME-AC-MBS-1
EIA485
A B
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+34 938047134
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