0-10V dimming in the electrical panel: actuators, wiring and polarity
0-10V and 1-10V still run a lot of commercial LED lighting, and most of what goes wrong with them gets decided at the DIN rail, not at the fixture. Here's how actuator wiring, polarity and current budgeting actually work together in the panel.
How 0-10V dimming is wired inside the panel
Generate the control signal
A DIN-rail 0-10V actuator/output module — common in KNX installations and standalone panel-based lighting control — converts a bus telegram or switch input into the 0-10V control voltage and distributes it to driver control terminals.
Route control and mains separately
The control pair carries only a few milliamps at low voltage — route, bundle and label it apart from the mains supply runs to the drivers; don't share a duct or terminal block between the two.
Match source/sink polarity
Both the actuator output and the driver's control input carry a source/sink marking inherited from IEC 60929 fluorescent-ballast practice. Wire the wrong combination or reverse polarity and dimming won't behave correctly.
Check the current budget both ways
There's no fixed number of drivers per output channel — check the actuator's rated output current and each driver's control-input current draw on their datasheets, and size the channel to the lower of the two.
What panel builders need to get right
1-10V never reaches zero on its own
A 1-10V-only driver dims down to a low floor around 1V, not off — full-off still needs a separate mains switch or relay downstream of the driver.
0-10V vs 1-10V, in practice
A compliant 0-10V driver can be commanded down to 0V and switched off through the control line itself; 1-10V's usable range only reaches down to 1V, so a 1-10V-only fixture needs a separate mains switch or relay to actually go dark.
Don't trust the label alone
Many drivers sold as '0-10V' actually behave like 1-10V in the field — dimming to a low floor rather than off. Check the driver's own datasheet before wiring the disconnect logic around it.
Source and sink must match
Source/sink describes which side of the pair supplies the current, a convention carried over from IEC 60929 ballast wiring. Actuator output and driver input must be compatible types with correct polarity, or the dimming curve won't track.
One control pair = one zone
0-10V is analog and not individually addressable — every driver on the same control pair dims together with no per-unit address or status feedback. A separate zone means a separate physical pair, decided at design time.
Size the channel from both datasheets
There's no universal drivers-per-channel figure — always check the actuator's rated output current against the summed control-input draw of the drivers it feeds, and leave margin.
What we help panel builders plan
Engineering input for the 0-10V dimming section of a panel build — not a parts catalogue.
- {'t': 'Actuator/output-channel sizing', 'd': 'Matching planned driver counts against real output-current and control-input-draw figures from both datasheets, not a rule-of-thumb number.'}
- {'t': 'Control-pair routing and labelling', 'd': 'Keeping the low-voltage 0-10V pair physically separate, ducted and clearly labelled apart from mains runs to the drivers.'}
- {'t': 'Source/sink and polarity verification', 'd': 'Checking actuator output type against driver input type before wiring, so the dimming curve behaves as specified.'}
- {'t': 'Zone planning at design stage', 'd': 'Working out which fixtures share a control pair and which need their own — 0-10V zoning is a wiring decision, not a software one.'}
- {'t': 'DALI vs 0-10V scoping', 'd': 'Helping decide, before wiring starts, whether the project actually needs individual/scene addressing (DALI) or zone-level dimming is enough (0-10V).'}
Frequently asked questions
What's the real difference between 0-10V and 1-10V?
On a compliant driver, 0-10V reaches 0V and switches off through the control line alone; 1-10V's usable range stops at 1V, a low but non-zero output, so a 1-10V-only fixture needs a separate mains switch or relay to go fully dark. Many drivers marketed as '0-10V' actually behave like 1-10V — check the datasheet rather than the label.
Is 0-10V the same as DALI?
No. 0-10V is an analog, non-addressable control voltage — every driver on the same pair dims together as one zone with no status feedback. DALI (IEC 62386) is digital and individually addressable, gives feedback, and needs its own commissioning step. Neither is simply 'better' — it depends on whether the project needs per-fixture/scene control (DALI) or zone-level dimming is enough (0-10V).
How many drivers can one 0-10V actuator output drive?
There's no fixed number — it depends entirely on the actuator's rated output current and the summed control-input current draw of the drivers wired to it. Always check both datasheets before finalising the channel, rather than assuming a round figure.
What does source/sink mean on an actuator's 0-10V output?
It describes which side of the control pair supplies the current — a 'sink' output absorbs current the driver sources, a 'source' output supplies current the driver sinks. The convention comes from IEC 60929 fluorescent-ballast practice and still appears on LED-driver datasheets; actuator and driver need compatible types and correct polarity.
Can I run several independently dimmed zones off one 0-10V system?
Yes, but each independent zone needs its own physical control pair wired from its own actuator output — 0-10V has no addressing, so zoning is decided at installation, not reprogrammed afterwards in software.
Planning a 0-10V dimming section for a panel build?
Send us the project scope and we'll work through actuator selection, control-pair routing and current budgeting with you before assembly starts.