Devices Guide - Smart (Components) Toolkit for Homey

Device Types Comparison

Feature	Composite Device	Logic Device	Logic Unit	Logic Unit X
Status	Current	Current	Current	Legacy
Setup Method	Visual pairing wizard	Visual pairing wizard	Quick add	Quick add
Input Configuration	Capability + source devices	Zone/room selection	Manual JSON	Manual JSON
Input Count	2 or more source devices	Dynamic (2-10, auto-expands)	Dynamic (2-10, auto-expands)	Fixed (2, 3, 4...10)
Formulas Per Device	Not applicable	Single formula	Multiple formulas	Multiple formulas
State Changed Trigger	✓ Aggregated value	✓ Yes	✗ No	✗ No
Best For	Sensor and alarm groups	Simple setups, beginners	Advanced users, multi-formula	Not recommended

⚠️ Legacy Devices

Logic Unit X (2, 3, 4...10 inputs) devices are still functional but deprecated. Use Logic Device or Logic Unit for new setups.

Composite Device

v1.10.22 test

Combines one shared capability from multiple Homey devices into one continuously updated virtual sensor or alarm.

• Numbers: average, minimum, maximum, sum, or median
• Alarms and booleans: any/maximum, all/minimum, majority, count on, or percentage on
• Clock and text values: average clock time, minimum/earliest, maximum/latest, most common, or most recently updated
• Resilient: continues with available sources and raises a Source Error alarm when a member is missing

Examples: highest humidity from five sensors, average room temperature, any open contact alarm, or the circular average of 23:00 and 01:00 (00:00).

Read Composite Device guide →

Logic Device

Recommended

The easiest way to create boolean logic devices with a visual pairing wizard.

Key Features

✓ Visual Setup Wizard - Browse zones/rooms to select devices and capabilities
✓ Dynamic Input Expansion - Starts with 2 inputs, auto-expands to 10 based on formula
✓ Single Formula - Simplified configuration for straightforward logic
✓ State Changed Trigger - Get notified on any state change with state token

When to Use

→ You're new to Smart (Components) Toolkit
→ You need only one formula per device
→ You want visual device selection during pairing
→ You want the "State changed" trigger

Setup Example

1. Devices → Add Device → Smart (Components) Toolkit → Logic Device

2. Pairing wizard:

• Input A: Living Room → Motion Sensor → alarm_motion
• Input B: Living Room → Lux Sensor → measure_luminance

3. Device Settings → Configure formula:

[
  {
    "id": "motion_light",
    "name": "Motion & Dark",
    "expression": "A AND B",
    "enabled": true
  }
]

Logic Unit

Advanced

Powerful device for advanced users who need multiple formulas or prefer JSON configuration.

Key Features

✓ Dynamic Input Expansion - Starts with 2 inputs, auto-expands to 10 based on formula
✓ Multiple Formulas - Configure multiple independent formulas per device
✓ Manual JSON Config - Full control over all settings
✓ Advanced Features - First Impression mode, timeout detection, isolated input states

When to Use

→ You need multiple formulas per device
→ You're comfortable editing JSON
→ You need advanced features (First Impression, timeouts)
→ You want maximum flexibility

Multiple Formulas Example

[
  {
    "id": "day_mode",
    "name": "Daytime Security",
    "expression": "A AND B",
    "enabled": true,
    "timeout": 60
  },
  {
    "id": "night_mode",
    "name": "Nighttime Security",
    "expression": "A OR B OR C",
    "enabled": true,
    "timeout": 30,
    "firstImpression": true
  },
  {
    "id": "away_mode",
    "name": "Away Mode",
    "expression": "(A OR B) AND NOT C",
    "enabled": false
  }
]

Each formula maintains its own input states and can be controlled independently.

How to Configure and Use It

Add Logic Unit (Dynamic) from Smart (Components) Toolkit.
Open the device's Advanced Settings and enter a JSON array in Formulas (JSON). Inputs are the letters A through J.
In a Flow, use Set input value for formula to set each input true or false. Use both the true and false branches of the source card so the Logic Unit always receives the current state.
Use Formula changed or Formula changed to... as a WHEN card, or Formula result is as an AND card.

Logic Unit Formulas JSON in Advanced Settings — Define the formula in Advanced Settings. This example creates `A AND B OR (C AND D)`.

Advanced Flow connecting contact alarms to Logic Unit inputs — Feed both true and false source branches into inputs, then react to the formula result. The screenshot shows the older fixed-input Logic Unit; the current Dynamic device uses the same pattern and adds formula selection.

Device Capabilities

Both Logic Device and Logic Unit share these standard capabilities:

alarm_generic

boolean

The aggregate formula result (true when any enabled formula is true)

• Exposed as the read-only Formula result alarm
• Can trigger Homey's standard alarm turned on/off cards
• Read-only (changes based on formula evaluation)
• Use the formula-specific Flow cards when a Logic Unit contains multiple formulas

onoff

boolean

Enable/disable the device

• User controllable (can be toggled in UI or flows)
• When OFF, formulas don't evaluate
• Use to temporarily disable logic without changing configuration

Dynamic Input Expansion

Both Logic Device and Logic Unit automatically expand inputs based on your formula requirements:

How It Works

1. Device created with 2 inputs (A, B)
2. You save formula: "expression": "A AND B AND C AND D"
3. Device detects formula uses C and D
4. Device automatically expands to 4 inputs (A, B, C, D)
5. New inputs appear in UI and flow cards

💡 Tips

• Maximum 10 inputs (A-J)
• Expansion happens on formula save
• Unused inputs are hidden but still available
• Works with all formula types (single or multiple)

Formula Isolation & Flow Behavior

⚠️ Important: No Flow Isolation

Within a formula, there is no isolation between flows. This is by design to allow formulas to work across multiple flows.

What This Means

Scenario: Multiple flows using the same formula

Flow 1: Set input A = true for formula "security"
Flow 2: Set input B = true for formula "security"
Flow 3: Triggered when formula "security" = true

Result: Flow 3 triggers when (A AND B) from different flows!

When You Need Isolation

If you need to use the same logic in multiple places within one flow with isolated states:

Solution: Create Multiple Device Copies

1. Create "Motion Light - Kitchen"
2. Create "Motion Light - Bedroom"
3. Each has the same formula but isolated state
4. Can be used independently in the same flow

💡 Pro Tip

For Logic Unit with multiple formulas: Each formula IS isolated from each other (formula "A" doesn't affect formula "B"), but each individual formula can be accessed from any flow.

Migration: Logic Unit X → Logic Unit/Device

⚠️ Legacy Device Warning

Logic Unit X (2, 3, 4...10 inputs) devices have fixed input counts and should be migrated to the new dynamic devices.

Migration Steps

1. Choose New Device Type
- • Single formula → Logic Device
- • Multiple formulas → Logic Unit
2. Copy Formula JSON
Go to old device settings → Copy the entire formula JSON
3. Create New Device
- • Logic Device: Use pairing wizard or paste JSON in settings
- • Logic Unit: Paste JSON in settings
4. Test Formulas
Verify all formulas evaluate correctly with test inputs
5. Update Flows
Replace old device references with new device in all flows
6. Remove Old Device
Once verified, delete the legacy Logic Unit X device

✅ Benefits After Migration

• Automatic input expansion (no need to choose 2, 3, 4...10)
• Future-proof (new features only added to current devices)
• Better performance with event-driven architecture
• State changed trigger (Logic Device only)

Best Practices

✓ Use Descriptive Names

Name devices and formulas clearly: "Motion Light - Living Room" instead of "Logic 1"

✓ Start Simple

Begin with Logic Device for single formulas, upgrade to Logic Unit when you need multiple formulas

✓ Test Formulas First

Use the Boolean Logic Emulator to verify expressions before deploying

✓ Use Device Copies for Isolation

Create separate device copies when you need the same logic with isolated states

✓ Leverage Dynamic Inputs

Don't worry about input count during setup - devices expand automatically based on your formulas

Device Types Guide

Device Types Comparison

Composite Device

Logic Device

Key Features

When to Use

Setup Example

Logic Unit

Key Features

When to Use

Multiple Formulas Example

How to Configure and Use It

Device Capabilities

alarm_generic

onoff

Dynamic Input Expansion

How It Works

Formula Isolation & Flow Behavior

What This Means

When You Need Isolation

Migration: Logic Unit X → Logic Unit/Device

Migration Steps

Best Practices

✓ Use Descriptive Names

✓ Start Simple

✓ Test Formulas First

✓ Use Device Copies for Isolation

✓ Leverage Dynamic Inputs