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Central unit configuration

Part 3 — Reference.

[☰]CU configuration


22.1 What this dialog does

Everything here configures the central unit itself — its network, its clock, and how it talks to the outside world. This is separate from your project: it is the CU's own settings.

Four tabs: CU setting, Cloud setting, Third part setting, MQTT setting.

The dialog shows two columns:

Column
Meaning

Project setting

What your project says the CU should be configured as

Actual setting

What the CU is actually configured as right now

When they differ, iDM3 asks you to choose — "Please select the correct setting". Read both carefully before deciding: picking the wrong one can take a CU off the network.

Save to CU writes the configuration to the central unit. When the CU's own configuration is pulled into your project you will see "CU configuration was saved to project."


22.2 CU setting

Network

Field
Meaning

IP address

The CU's address — this is what you connect to

Mask

Subnet mask

Gateway

Default gateway

IP address2 / Mask2 / Gateway2

A second interface or address

DNS1 / DNS2

Name servers

Changing the IP address changes how you reach the CU. Write the new address down before you apply it. If you lose contact, recovery means physical access to the unit.

Time

Field
Meaning

NTP server

Time server the CU synchronises with

Time zone

The CU's time zone

CU time

The CU's current clock

IDM time

Your PC's clock, for comparison

Get the time right. Every time program, heating schedule, and the astronomical module's sunrise and sunset calculation depends on it. A CU with the wrong time zone runs the whole building an hour out.

Errors

Field
Meaning

Error code:

The CU's current error code

Title: / Body: / ExtendedInfo: / Code:

Details of the error

Reset error

Clears it

Clear an error only after you have read it and understood the cause. See Chapter 30.


22.3 Cloud setting

Field
Meaning

Mode:

Cloud connection mode

User name:

Cloud account

Password:

Cloud password

Connects the installation to the iNELS cloud service, which is what phone apps and remote access use.

Cloud credentials are credentials. They are stored in the project. Treat .elp files containing them accordingly.


22.4 Third part setting

The plain-text protocol that lets other systems talk to the CU.

Field
Meaning

Port

TCP port to listen on

Mode

Protocol mode

Separator

Character separating fields

Numeral system

How numbers are represented

Event enable

Whether the CU sends events as they happen, or only answers queries

Only devices marked Add to iNELS 3 export are visible over this protocol — see Chapter 24.

Turn on Event enable if the other system should react to changes; leave it off if it only polls. Polling a busy installation is much heavier than receiving events.


22.5 MQTT setting

Field
Meaning

Mode:

MQTT mode

User name:

Broker username

Password:

Broker password

Version:

MQTT protocol version

MQTT lets the installation publish to a message broker — the usual route into home-automation platforms.

MQTT is one of the significant additions since the Rev19 manual, which does not cover it at all. Supported units and firmware requirements are listed in Advance/Documentation/BUS unit to MQTT.txt, and summarised in Chapter 24.

MQTT requires recent CU firmware — from 02.97.02 for CU3-07M, CU3-08M and CU3-09M. Check Chapter 25 before configuring it.


22.6 Before you change anything

Write the current settings down

Especially the IP address

Check Project setting against Actual setting

Know which one you are keeping

Confirm the time zone and NTP server

Everything time-based depends on them

Confirm firmware first for cloud and MQTT

Both need recent CU firmware

Test the connection after saving

Use Ping test in Settings


Next: Chapter 23 — Connecting and uploading.