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IHC to Shelly conversion
Schneider Electric has discontinued the IHC controller, and we have since converted many of these installations to Shelly. Replace only the modules in the panel, and reuse the existing wiring and buttons.
Updated: September 2026
The conversion calculator
Count the inputs, outputs and dimmer channels in the existing panel, and the calculator turns them into a complete parts list.
It reflects our recommendations. Other combinations work; treat it as a starting point rather than a specification.
Three methods
Three ways to do the same job. You do not have to pick one — most conversions combine them, with each circuit on whichever method suits it.
Method 1 — wired latching relay
The stable one
The button drives its own output through the panel wiring. Basic on/off works with no network at all. Changes mean rewiring in the panel.
Method 2 — input/output
Classic input/output
Separate input and output devices, linked in software. The most flexible, and the one that depends on the network being up.
Method 3 — wireless buttons
The replacement for IHC Wireless
Battery buttons where no cable runs, or where a new switch position is wanted. The existing buttons are not reused.
Method 1 — wired latching relay
The input conductors are gathered onto the input that drives the output on the same device. The result works purely by wire, and keeps working when the network does not.
It is still smart: with the network up, lights can be grouped, scheduled and controlled from the app, and a double or long press can drive other relays.
Pros
- Basic on/off always works — no Wi-Fi, no cloud, no gateway
- No programming for plain on/off
- No single point of failure
Cons
- Changing which button drives which output means rewiring in the panel
- Less flexible than method 2
- No power metering on Shelly Pro 1, Pro 2 or Pro 3
- Panels in several locations may still need a wireless link between them
Recommended relays
All three are supplied with 24 V DC or 230 V AC. The 24 V low-voltage buttons only work when the device is supplied with 24 V DC; the 230 V load is switched through the potential-free contact either way.
2 inputs, 1 output, 1 module. Input 1 drives output 1; the second input is free to program.
2 inputs, 2 outputs, 1 module. Four of them fit in four modules and give 8 outputs — as many as one IHC output module carries.
3 inputs, 3 outputs, 3 modules. Cheapest per output, and the widest — check the panel before you specify it.
Recommended dimmers
Dimming is still possible on this method. Shelly Pro Dimmer 1PM and Shelly Pro Dimmer 2PM are 230 V devices, so a low-voltage button cannot drive them directly: fit an interface relay with a 24 V coil between the button and the dimmer — a 24 V interface relay, 1 changeover (elsag.dk) or equivalent — or control the dimmer wirelessly instead.
One dimmer channel with power metering.
Two dimmer channels, power metering on each.
Method 2 — classic input/output
The same thinking as the original installation: separate input modules and output modules. The difference is that the router — or the Shelly cloud — is the hub instead of the IHC controller.
Pros
- Very flexible; any button can drive any output
- Low voltage and mains can stay separated in the panel
- Programming works across panels
Cons
- Depends on the local network, or on the internet
- More programming
- Separate input and output devices, so more space
As an input module
5 inputs, reading short, double, triple and long press. Four of them give 20 inputs in the width of one LK IHC 16-input module.
It is sold as a 12–24 V LED controller, and it is a good one — but it is also the closest thing to a direct replacement for an IHC input module. The outputs do not have to be used. The inputs alone can drive relays and dimmers elsewhere on the network, which is exactly the input-module role.
As outputs
Relays with power metering. They are driven from the input module over the network.
One 230 V output with power metering.
Two 230 V outputs, metering on each. Also runs as a shutter controller.
Four 230 V outputs, metering on each, in 53 mm — up to four per DIN rail row.
Shelly Pro 1, Pro 2 and Pro 3 carry both inputs and outputs, so one device can replace an input module and an output module. They have no power metering.
One output and two inputs on the same device — it can replace both the input and the output.
Two outputs and two inputs, 1 module.
Three outputs and three inputs, 3 modules. Cheapest per output.
Dimmers. Both are 230 V devices, driven from the input module over the network.
One dimmer channel with metering.
Two dimmer channels, metering on each.
This guide covers choosing hardware and installation method. For help with setup, contact nordics@shelly.com.
Method 3 — wireless buttons
Battery buttons replace the wall buttons, paired with the device they control. This is the method that replaces IHC Wireless.
Pros
- Works where no cable runs
- A new switch position costs a button, not a chase in the wall
- Power metering is available, because the output can be any PM device
Cons
- The existing buttons are not reused — that is its one real cost
- Limited by radio range
Four buttons in a Danish faceplate, battery powered, no wiring behind it.
The same switch in grey.
For dimming from a wireless button, see dimming with BLU Wall Switch.
Combining the methods
You do not have to pick one method for the whole house. Pick the one that suits each button:
- Method 1 for buttons that switch or dim a single light. They keep working when the network is down.
- Method 2 for buttons that drive several lights at once, or set a scene.
- Method 3 where a new button has to go up and no cable runs there.
The diagram shows how an installation can be wired when the methods are combined: Shelly Pro 1, Pro 2 and Pro 3 with 24 V directly on the inputs, an interface relay for the dimmer, and a Shelly Pro RGBWW PM as the input module beside a Shelly Pro 4PM.
Tips & best practices
- Survey before you quote. Count inputs, outputs and dimmer channels per panel. The calculator turns that count into a parts list; nothing turns a guess into one.
- Pick a method for each button. Anything that has to work without the network belongs on method 1.
- Check panel width early. Shelly Pro 3 is the cheapest per output and the widest. In a full panel that trade-off decides the design.
- Keep the existing power supply if it is healthy. It is already sized for the low-voltage side, and replacing it adds cost for nothing.
- Label the panel as you go. A converted IHC panel looks nothing like the drawing on the door, and the next electrician will have only your labels to work from.
Video tutorial
A full conversion of a 24 V low-voltage installation, with what to watch for along the way.
Loads YouTube when you press play. Watch on YouTube
By ShellyGuide on YouTube
This video is in Danish. Auto-translated subtitles are available in the YouTube player settings.