Datapoint Types (DPT) — quick reference
The DPTs you will encounter 80 % of the time
The most commonly used DPT families in KNX, with size, range, meaning and concrete examples. Printable single-sided A4 to keep at hand during ETS programming.
📊 Main families
| Family | Size | Type | Example sub-types |
|---|---|---|---|
| DPT 1.xxx | 1 bit | Boolean | 1.001 Switch (on/off), 1.007 Step, 1.008 UpDown, 1.009 OpenClose |
| DPT 2.xxx | 2 bits | Bool + control | 2.001 Switch with control, etc. |
| DPT 3.xxx | 4 bits | Dimming control | 3.007 Control_Dimming (step-by-step) |
| DPT 5.xxx | 1 byte | Unsigned 8-bit | 5.001 Scaling 0-100 %, 5.003 Angle 0-360°, 5.010 Counter Pulses |
| DPT 6.xxx | 1 byte | Signed 8-bit | 6.001 Percent_V8 (-128 to +127), 6.010 Counter signed |
| DPT 7.xxx | 2 bytes | Unsigned 16-bit | 7.001 Counter (0-65535), 7.005 Time s, 7.012 Current mA |
| DPT 8.xxx | 2 bytes | Signed 16-bit | 8.001 Counter signed, 8.010 Percent_V16 |
| DPT 9.xxx | 2 bytes | Float 16-bit | 9.001 Temperature °C, 9.004 Lux, 9.007 Humidity %, 9.020 Voltage mV |
| DPT 10.001 | 3 bytes | Time of Day | Time + day of week |
| DPT 11.001 | 3 bytes | Date | dd/mm/yy |
| DPT 12.xxx | 4 bytes | Unsigned 32-bit | 12.001 Counter long |
| DPT 13.xxx | 4 bytes | Signed 32-bit | 13.010 Active energy Wh, 13.013 Active energy kWh |
| DPT 14.xxx | 4 bytes | Float 32-bit IEEE 754 | 14.056 Power (W), 14.068 Temperature K |
| DPT 16.xxx | 14 bytes | String ASCII | 16.001 Char string (max 14 characters) |
| DPT 17.001 | 1 byte | Scene Number | Scene recall 0-63 (recall only) |
| DPT 18.001 | 1 byte | Scene Control | Recall + Learn (1 bit + 6 scene bits) |
| DPT 19.001 | 8 bytes | DateTime | Full date + time |
| DPT 20.xxx | 1 byte | Enum | 20.102 HVAC Mode, 20.105 HVAC Control Mode |
| DPT 28.001 | variable | String UTF-8 | Multi-byte, accents and non-Latin |
| DPT 232.600 | 3 bytes | RGB | Colour (R, G, B) |
| DPT 251.600 | 6 bytes | RGBW + dimming | Colour + white + intensity |
🎯 Typical use cases by function
On/off lighting
- Command: DPT 1.001 (Switch) — W flag enabled
- Status feedback: DPT 1.001 (Switch Status) — T + R flags enabled
Dimming
- On/off: DPT 1.001
- Step-by-step: DPT 3.007 (held = continuous +/-, released = stop)
- Absolute value: DPT 5.001 (0-100 %)
- Value status: DPT 5.001 status
Blinds / roller shutters
- Up/Down: DPT 1.008 (UpDown) — long press
- Step/Stop: DPT 1.007 (Step) — short press
- Position: DPT 5.001 (0 % = top, 100 % = bottom)
Heating control
- Measured temperature: DPT 9.001 °C (sensor emits)
- Setpoint: DPT 9.001 °C (BMS sends)
- HVAC mode: DPT 20.102 (Comfort/Standby/Eco/Building Protection)
- Valve: DPT 5.001 % (0-100 %)
Scenes
- Simple recall: DPT 17.001 (number 0-63)
- Recall + save: DPT 18.001 (1 learn bit + 6 scene bits)
Energy measurements
- Active energy: DPT 13.010 Wh or DPT 13.013 kWh
- Instantaneous power: DPT 14.056 W
- Voltage: DPT 9.020 mV
⚠️ Classic pitfalls
Pitfall 1 — Semantics vs size
Several 1-bit DPTs exist (1.001, 1.007, 1.008, 1.009...): same size, different meaning. ETS binding enforces the semantics but the raw telegram is identical. Confusing 1.001 (switch) with 1.008 (up/down) is a classic mistake.
Pitfall 2 — Float 16-bit (DPT 9.x)
The precision is not double. For precise values (>3 significant decimals), prefer DPT 14.x (float 32-bit IEEE 754).
Pitfall 3 — DPT 17 vs DPT 18
- 17.001 = scene recall only
- 18.001 = recall + save (1 "learn" bit)
- Frequent mistake: using 17 when the user needs to be able to save.
Pitfall 4 — Compatible sizes in binding
ETS refuses to associate group objects of different sizes. A 1-bit object cannot be associated with a group address already bound to an 8-bit object (even if the DPT is compatible).
💡 Key takeaways
- Family 1.xxx = booleans (8 common sub-types to know)
- Family 5.xxx / 9.xxx = the majority of residential and commercial
- Family 13/14.xxx = counters and precise measurements
- Family 17/18 / 20 = scenes and modes
- Family 232 / 251 = colour (RGB / RGBW LEDs)
Sources:
- KNX Specifications V3.0.0, Vol. 3/7/2 — Datapoint Types
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