What kind of DALI products does RESI produce ?
We produce a powerful DALI master gateway, which supports DALI 1.0, DALI 2.0, DALI DT6, DT8. Also this gateway supports DALI 2.0 multi master standard to communicate with DALI 2.0 sensors and input devices.
Our DALI master gateway with serial RS232 or RS485 interface and MODBUS/RTU slave or ASCII text protocol:
RESI-DALI-SIO: with either RS232 or RS485 interface to host
RECOMMENDATION: use our RESI-DALI-PS power supply to power your DALI bus system!
Our DALI master gateway with Ethernet interface and MODBUS/TCP server or ASCII text socket protocol:
RESI-DALI-ETH: with Ethernet interface to host
RECOMMENDATION: use our RESI-DALI-PS power supply to power your DALI bus system!
We have a project involving DALI2 devices and I would like to use a RESI module.
There are some occupancy/light sensors. Is it possible to configure in the RESI MODBUSconfigurator tool the behavior of lights depending on the sensor?
Yes, our RESI-DALI-SIO and RESI-DALI-ETH support the use of DALI 2.0 sensors. We have done a new firmware (V5.0.0 or better) for both products, which we deliver since January 2026 as standard firmware.
This firmware allows the full configuration and commissioning of DALI 2.0 devices and the firmware can react to the DALI 2.0 events internally. So with this firmware, you can build a DALI 2.0 solution in using DALI 2.0 occupancy/light sensors or push button devices together with DALI 1.0 lamps.
But your controller must have some prerequisites to use this features.
We suggest, that we do a brief online meeting to discuss your demands in your project (Which type of sensors, how many of them, what kind of functionality,..) Please contact us via mail under RESI help to check out our desired solution and to schedule an online-meeting, if necessary.
DALI cabling topology
The DALI allows any kind of cable topology like line, star or tree. Only a ring topology is forbidden! Maximum cable length is in total 300m
depending on the following parameters: type of cable, communication speed, maximum number of connected DALI devices!
Maximum DALI cable length
The maximum cable length results from the maximum permitted voltage drop on the DALI cable; it is defined as a maximum of 2 V.
This corresponds to a maximum cable length of 300 m with a cable cross-section of 1.5 mm².
CAUTION: When designing the maximum cable length, the contact resistances must also be observed!
2 V voltage drop must not be exceeded!
Do you have more than 64 DALI ballasts on a DALI line with a DALI power supply?
DALI only allows a maximum of 64 ballasts on a bus line!
Divide the DALI bus into two separate bus lines and use two DALI power supplies
Is your bus system longer than 300m?
Separate the bus system into several separate segments with your own DALI power supplies and DALI master
Measure the DALI output voltage on the DALI-MASTER. This must be around 14V!
Too many lights with ballasts on the DALI bus?
Do the ballasts use more power than the DALI power supply can deliver?
Usually the DALI power supplies deliver 200mA or 250mA of current
Does the DALI voltage drop at the ballasts?
There may be a maximum voltage drop on the DALI bus of 2V between the DALI supply and the DALI ballast.
In the event of a large voltage drop, DALI communication no longer works reliably!
Measure this with EVERY ballast using a voltmeter!
First check whether all DALI devices are working.
Make sure that there is no communication on the DALI line.
Measure the voltage on the DALI power supply.
The value must be between 11.5 V and 22.5 V; a typical value is 14-16 V.
A significantly lower value could indicate a short circuit.
Measure the voltage on the DALI device that is furthest away from the DALI power supply.
The value must be between 9.5 V and 20.5 V.
A much lower value indicates that there is a short circuit somewhere.
Create a short circuit between the two DALI bus lines on the DALI device that is furthest away from the DALI power supply.
Measure the voltage on the DALI power supply. The value you measure is the DALI voltage drop.
This value must not be higher than 2 V.
If it is higher than 2 V, check whether the following events have occurred:
DALI line too long (over 300m with 1.5mm² cross-section)
Cross section too small
High contact resistance
The value must be brought below 2 V.
Remove the short circuit between the two DALI bus lines furthest away from the DALI device.
This can be solved by dividing the DALI bus system into two separate DALI bus systems
Your DALI bus cabling must be a tree structure
There must be no ring or loop. If so, cut this loop open!
Recommendations of DALI cable lengths for different conductor cross-sections:
DALI cable length
at Ø 1.5mm² max. 300m
at Ø 1.0mm² max. 238m
at Ø 0.75mm² max. 174m
at Ø 0.5mm² max. 116m