Local Lan Network Management; Purpose Of The Local Lan Network; Preliminary Operations; Introduction - Mitsubishi Electric s-MEXT-G00 006 Technical Manual

TM_s-MEXT_ME28relC_00_12_19_EN
20

LOCAL LAN NETWORK MANAGEMENT

20.1

PURPOSE OF THE LOCAL LAN NETWORK

Connecting the units to the LAN network (meaning the PCO boards mounted on each unit) allows the following functions to be performed:
•
Balancing the operating hours among the different units by rotating the reserve units (Stand-by).
•
Turning on the reserve units in case other units should turn off due to an alarm, maintenance or power feed interruption.
•
Turning on reserve units to offset the excessive thermal load.
•
Checking up to 10 units with a single user terminal (shared user terminal).
•
Operating with all units based on the average temperature and humidity values read by the temperature probes only in the operating units.
OBLIGATION
To allow the LAN to operate correctly, the units must have the same software version and revision (e.g.: ME28r00).
If there is more than one version, update to the latest version or create two different LAN's.
20.2

PRELIMINARY OPERATIONS

20.2.1

Introduction

As the BIOS contained inside the control board is already fitted out to manage a local network connection of the board:
•
It cyclically performs a check-up of the hardware (of the local board) required for network communication and of its settings (for example, the network address,
which must be different from 0).
•
It cyclically performs a check-up of the connection status of the local unit with the rest of the LAN.
•
It cyclically performs a global check-up of the rest of the LAN which can be seen by the unit in question.
•
It cyclically performs the transmission and reception routine of the variables of the local unit involved in transmission.
For correct operation of the units connected to the local LAN network, it is necessary to perform the following operations.
20.2.2

Network cabling

For the purposes of setting a local LAN network among the units, it is necessary for the installer to lay an electrical connection among the same by means of a screened
cable (not included in the supply).
INFORMATION
it is recommended to use twisted couple of AWG24 cabling (2 wires in total) + Belden 8723 or 8102 type sheath.
ATTENTION
the electrical connections must be installed when the units are off and not fed. The LAN serial low safety voltage (SELV) cabling must be
kept safely far from the power cables.
ATTENTION
The electrical connections must be installed by qualified staff, when the unit is off and not fed.
ATTENTION
The connections must be made directly on the unit main terminal board: The RX/TX+, RX/TX-, and GND connection terminals do not vary
from unit to unit and are clearly indicated on the electrical diagram on board the unit.
All control boards being part of the local network are connected according to a bus arrangement.
The following image shows the type of connection to be made:
Controllore Unità 1
Unit 1 controller
Technical manual
Cable shield
Schermo cavo
Controllore Unità n
Unit n Controller
Figure 20-1: Example of local network (LAN) electrical connection
Controllore Ultima Unità
TRANSLATION OF THE ORIGINAL INSTRUCTIONS
107
Last Unit Controller