Settings On The User Terminal; Backup Unit Management (Stand-By); Introduction; Rotation Management - Mitsubishi Electric s-MEXT-G00 006 Technical Manual

TM_s-MEXT_ME28relC_00_12_19_EN
20.3

SETTINGS ON THE USER TERMINAL

In the case of units connected to a local LAN network, indicate the total number of connected units on the Master unit, then, if needed, enable the functions provided by the
LAN, which are the following:
•
Regulation based on the temperature and humidity average value read by all network units.
•
The presence of one (or maximum two) backup units in rotation and, if need be, ready to kick in in the presence of extreme room temperature and humidity
conditions.
The configuration parameters for the LAN network are under the Lan menu, which can be accessed by entering the "Service" password.
More specifically, the settable parameters are:
•
Number of units connected to the local LAN network.
•
Enabling average calculation functions in LAN.
•
Enabling the backup unit and its rotation.
•
Interval of time between one rotation and the next (in other words: stand-by time.
•
Number of backup units (fixed from 1 to 3 LAN units, selectable between 1 or 2 for networks from 4 to 10 LAN units).
•
Enabling the start function for the backup units when exceeding the room temperature and humidity limits.
20.4

BACKUP UNIT MANAGEMENT (STAND-BY)

20.4.1

Introduction

In an installation made up of on units and stand-by units, there may be imbalances in the operating hours that cause the former to age faster because of the failure to use the
latter. In order to solve this problem, the local network (LAN) always runs unit rotation in order to even out the operating hours. Basically, the rotation puts an active unit in
stand-by and turns on a unit that was previously in stand-by.
20.4.2

Rotation management

The rotation of the reserve unit is managed entirely by the address 1 unit (which in this case acts as Master unit, while all the others are Slaves) and is based on time
parameters, starting from the unit with the lower address, that is, address 1, and works its way up. Two reserve units can be set, but only when there are at least three units
connected to the local LAN network. In this case, the units are rotated in standby starting with the first two (addresses 1 and 2) and then the second two (2 and 3) and so
forth.
The parameter for configuring the rotation time is in the "Lan" menu, which can be accessed by entering the "Service" password.
INFORMATION
If the rotation time interval is set to zero, from that moment on rotation no longer takes place, and therefore the backup unit always remains the same,
only becoming active if the faults and alarms indicated in the following sections occur.
INFORMATION
It is possible to manually force the rotation of the reserve unit using a dedicated command found in the "Manual" menu, which can be accessed by
entering the "Service" password. For safety reasons, an interval of 10 minutes (fixed time that cannot be changed) is necessary between one forcing
and the next. The time remaining until the next instance of forcing is indicated in the forcing mask.
20.4.3

Reserve unit activation mode

The stand-by unit comes out of its "idle" state and activates under the following circumstances:
• An alarm blocks an active unit.
•
One of the active units is turned off from the user terminal.
• Local LAN disconnection detected (including power feed disconnection of one or more units).
•
Exceeding the set room temperature and humidity limits.
As regards the first two bullet points, turning on the stand-by unit is entirely managed by the unit having address = 1 (Master).
Technical manual
TRANSLATION OF THE ORIGINAL INSTRUCTIONS
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