Common questions — support index

Support index — a symptom or question, and the chapter that answers it.

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This page exists to get you from a customer's words to the right chapter fast. It is phrased the way people actually ask, not the way the manual is organised.

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"It doesn't work"

The customer says	Likely cause	Chapter
The button does nothing at all	Icon not assigned — yellow dot on the floor plan	30 §30.1 · 17 §17.4
I uploaded but nothing changed	Saved the file but never did Save to central unit	23
It worked before, now it doesn't	The CU is running a different project	23 §23.6
Some devices are missing / disconnected	Addresses don't match the hardware	16
The relay clicks but the light stays off	The project is right — the fault is electrical	26 §26.5
Nothing responds after a power cut	Non-volatile not set; no System start wire	12 §12.4

Lights and switching

The customer says	Answer	Chapter
The button only turns the light on, never off	Digital switch ON isn't a toggle — use DIGITAL_SWITCH	6 §1
I want a staircase light that switches itself off	Impulse function with an impulse time	6 §2
Pressing again doesn't restart the timer	Digital_Impulse_ON ignores an output already on — use a timer	12 §12.2
I want one button to do two things	Two actions on one wire — Short down and Long down	6 §4
I want a delay before it switches off	Digital delay switch OFF	6 §5
How do I switch everything off from one button	A group	8

Dimming

The customer says	Answer	Chapter
The light runs to 100% after I let go	Missing Analog stop changing level on Long up	7 §3
Holding the button doesn't dim	Needs Analog increasing level on Long down	7 §3
The dimmer forgets its brightness	Analog switch value only moves 0%↔100% — needs a system integer	12 §12.5
My 10-second ramp only takes 2 seconds	Ramp length is the 0→100% time; partial changes are proportional	7 §5
I want the light to fade, not jump	Analog set level w ramp	7 §5
I want a specific brightness on one press	ANALOG_SET_LEVEL_25/50/75	7 §4

Blinds and shutters

The customer says	Answer	Chapter
How do I control blinds	Digital impulse — short time tilts, long time runs full travel	9
The blind won't stop when I press again	Digital_Impulse_ON ignores an active output — add an explicit stop	9 §4
The blind doesn't reach the end	Impulse time shorter than real travel time	9 §5
The slats tilt too far	Reduce the tilt impulse time	9 §5
Can blinds close at sunset	Astronomical module	11 §11.2

Heating and cooling

The customer says	Answer	Chapter
Heating doesn't come on	Check Monitor → Heat/Cool areas first	30 §30.8
The temperature is wrong	The time plan, or which plan the area uses	20 §20.6
How do I set a heating schedule	Time plan, then Heat/Cool area	10
Heating and cooling run at the same time	Check the difference between… → On	20 §20.7
One room never heats	That room's Heating output	20 §20.7
No room heats	The shared Heating supply	20 §20.7
How do I protect against freezing	Antifreeze temperature on every area	10 §10.4
What are Favorite1–4	The four preset temperatures	10 §10.3
Holiday mode for heating	Holiday plan + a continuous program	10 §10.6

Timers, counters, logic

The customer says	Answer	Chapter
Corridor light should restart on movement	A timer — Timer start restarts a running timer	12 §12.2
I want to count something	A counter	12 §12.3
How do I remember a state	A system bit, non volatile	12 §12.4
Holiday mode is lost after a reboot	non volatile wasn't ticked	12 §12.4
Only do this if it's dark / cold / off	A condition	12 §12.6
What do system bits and integers do	Storage the whole project can read and write	20 §20.4

Schedules and time

The customer says	Answer	Chapter
Do something at a set time	A Periodical program	11 §11.3
On for part of the week	A Two-state program	11 §11.4
Between two dates	A Continuous program	11 §11.5
I can't save my program	No day or month ticked	11 §11.3
Sunset switching is an hour out	The CU's Time zone	22 §22.2
Lights on at dusk all year	Astronomical module with a sunset offset	11 §11.2

Connection and upload

The customer says	Answer	Chapter
I can't connect to the central unit	Ping test first	23 §23.2
It says BadPassword	Wrong CU password	23 §23.3
It says UpdateRequired	CU firmware too old	25
Compile error	Click the button and read it	30 §30.3
I lost the project file	Load from central unit	15 §15.6
How do I change the CU's IP address	CU configuration	22 §22.2

Groups, scenes and reuse

The customer says	Answer	Chapter
A light won't join my group	Wrong group type — relays and dimmers can't share one	8 §The four group types
How do I build a scene	Separate wires with different levels, not a group	8 §5
The group function names look wrong	Untranslated in 3.5.3 — GroupDigital_SwitchOn is normal	8
I keep building the same thing	Macros, or function blocks	14
My macro didn't apply	Its Type doesn't match the actor type	14 §14.2
Editing the macro changed nothing	Macros are copied into wires, not linked	14 §14.2
A function block does nothing	Inputs/outputs not plugged in, or Connect not pressed	14 §14.3
A colleague can't open my project properly	Function block templates live outside the .elp	14 §14.3

Hotel installations

The customer says	Answer	Chapter
Rooms don't show up in iNELS Harmony	No Hotel-Room object — Harmony discovers rooms from it	34 §34.1
What is the Hotel-Room object for	One object per guest room: status, climate, scenes	34 §34.1
Where do I enter the room number	Room-Id on the Hotel-Room unit — not the Address	34 §34.3
Guest can set a temperature but nothing happens	Heat/Cool area outputs never wired to hardware	34 §34.5
How does the PMS read a room	One MQTT topic pair per room	34 §34.8
DND light doesn't match the button	Drive the backlight from the DND datapoint	34 §34.6
Empty rooms stay warm	Wire Occupancy off → setback	34 §34.7

Integration

The customer says	Answer	Chapter
Can I use it with Home Assistant	MQTT	24 §24.4
MQTT isn't working	Needs CU firmware 02.97.02 or later	24 §24.4
Can I read an energy meter	Modbus master	32 §32.5
Can a BMS read the installation	Modbus slave	32 §32.7
Does it do Modbus RTU or just TCP	Both — but RTU needs a CU3-10M	32 §32.3
Internal-Modbus-Master isn't in the list	The CU isn't a CU3-10M	32 §32.3
RTU meter, but the site has a CU3-08M	Gateway, CU swap, or GRT3-100 master	32 §32.3
Which CU do I need for Modbus	IP: any. RTU: CU3-10M only.	32 §32.3
Can two central units talk to each other	Yes — Modbus IP	33
Button on one CU, light on another	Link them over Modbus IP	33
CU link worked, then stopped	The slave CU's IP changed — DHCP	33 §33.8
Value moves on one CU, not the other	Register address, data type or scaling differs	33 §33.8
How do I share a temperature between CUs	One register, Multiplication 10x both sides	33 §33.10
Modbus reads nothing at all	A/B swapped, wrong baud, wrong slave address	32 §32.10
Modbus works with 2 devices, fails with 5	Termination or topology	32 §32.4
Temperature reads 215 instead of 21.5	Scaling — set the multiplication factor	32 §32.10
Every Modbus value is one register out	Register number vs offset (40001 vs 0x0000)	32 §32.5
Can I control a Carrier air conditioner	Yes, via a CCN→Modbus translator	32 §32.8
The external system can't see a device	It isn't marked Add to iNELS 3 export	24 §24.2
A phone app for the client	Cloud	22 §22.3

DALI

The customer says	Answer	Chapter
How do I address DALI ballasts	CU3-09M: Dali manager. RC3-610M: externally.	21 §21.1
Which CU do I need for DALI	CU3-09M — or an RC3-610M/DALI unit	21 §21.1
Dali manager doesn't see my ballasts	The CU isn't a CU3-09M	21 §21.1
RC3-610M DALI lights don't respond	Ballasts must be addressed externally first	21 §21.6
DALI bus completely dead	DALI needs its own power supply	21 §21.1
All my DALI lights control the wrong fittings	Someone ran New DALI on a live system	21 §21.3
Which fitting has failed	Lamp failure in the Dali manager status	21 §21.5
Duplicate DALI address	Red exclamation mark — use Delete address	21 §21.4

Messaging

The customer says	Answer	Chapter
SMS never arrives	The GSM: plug is red, not green	13 §13.4
Can it text me when something happens	Yes — GSM3-01M required	13
My text to the system does nothing lasting	Incoming SMS is a one-second pulse	13 §13.4
Message got cut off	32-character limit	19 §19.6

Software and versions

The customer says	Answer	Chapter
Where do I download iDM3	Software Download	3
Which central units are supported	CU3-08M / 09M / 10M; CU3-07M obsolete	1 §1.2
Is EST3 / EHT3 still available	Obsolete — use a GSB3 or similar	Appendix D
What's the difference between Short down and Short up	Down = press, up = release	2 §2.2
Why does it say "for CU3-07M"	Historical naming	3 §3.2
My old project won't open properly	Needs conversion — and a connection to the CU	28
A unit isn't supported any more	Unavailable units	28 §28.4
iDM3 won't start	.NET Framework 4.8; check Exception.excp	3 §3.7
Where are the log files	The install folder	30 §30.6
It's very slow	Turn off the two animations	30 §30.6
I've run out of wires / bits	Prefernces shows the limits	27 §27.3

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Things that look like bugs but aren't

Worth checking before escalating — each is documented behaviour:

Behaviour	Why
Second press does nothing	Digital switch ON is not a toggle
Impulse won't re-trigger	Digital_Impulse_ON ignores an output already on
Light climbs to full after dimming	No Analog stop changing level on Long up
Ramp finishes early	Ramp length is the 0→100% time
Group function names look raw	Untranslated in 3.5.3
Alarm_Refeshed is misspelled	It is — in the software
Menu says "Prefernces"	It does
New unit greyed out	Wrong item selected, or a limit reached
Editing a macro doesn't change existing wires	Macros are copied, not linked

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See also: Chapter 30 — Troubleshooting · Appendix E — Glossary · index