DALI error status

Error status in DALI System

The gateway allows the error status of DALI operating devices to be indicated. The general status "Error in DALI system" can be used if individual evaluation and indication of the error status of individual electronic ballasts or groups and single devices is not required or is to be supplemented with a status function, independent of the electronic ballast. This status function has the 1-bit communication object "Status - Error – DALI system", which allows a general error to be indicated in the DALI installation. The gateway sets the object value to "ON" as soon as it detects an error in a previously commissioned DALI operating device. Here, it is irrelevant which error was identified by the gateway (lamp error, electronic ballast error). The gateway does not reset the object value to "OFF" until all the previously identified errors have been eliminated.

The error status of DALI sensors cannot be queried via the gateway.

To use the status function, the parameter "Error in DALI system" must be activated on the parameter page "DALI system... -> General" be activated. The parameter "Telegram repetition with new error" determines whether status telegrams are generated repeatedly if several errors occur in the DALI system in succession.

Setting the error status in the DALI system

The error status in the DALI system is implemented as an active signalling object. The gateway automatically transmits the status to the KNX with every change.

An error status saved in the gateway in the DALI system is lost when the mains voltage fails. For this reason, after all the errors have been eliminated by switching the mains voltage off and on again at the gateway, no status is transmitted any more.

The gateway initialises after switching on the mains power supply or after an ETS programming operation. If a DALI error is detected in this state, the gateway also transmits an appropriate status telegram. After the bus voltage returns (mains voltage switched on permanently at the gateway during a bus failure), the feedback is not automatically sent to the KNX.

Optionally, the error status in the DALI system can be transmitted repeatedly, if, after a previously identified DALI error, further errors are detected on the same or other operating devices. The parameter "Telegram repetition with new error" defines the behaviour of the general error status in the event of new errors.

Error status per DALI operating device

The gateway allows the feedback of the individual error status of DALI operating devices in up to two different data formats. To use this feedback function, the parameter "Error per DALI control gear" must be activated on the parameter page "DALI system... -> General" be activated. The parameter "Data format" that is then available determines whether only a 1-byte object (according to KNX DPT 238.600), a 2-byte object (according to KNX DPT 237.600) or a combination of both objects is used.

The status information "Lamp error" or "Error in operating device (e.g. electronic ballast error)" is transmitted to the Gateway by the DALI components if there is an error, and is saved there. The gateway makes all the status information about the KNX-side error status objects available. The object values are evaluated in bit-orientated fashion according to the selected data format. A feedback telegram always transmits the status information of only one DALI operating device.

As the master in the DALI system, the gateway - as soon as it is ready for operation - queries the status of the commissioned electronic ballasts (slaves) cyclically every second. A system with a maximum of 64 DALI devices can identify an error after 63 seconds at the latest. Once an error has occurred in the operating device, it must be eliminated (switch off the mains voltage to the appropriate DALI subscriber and observe the manufacturer's information!). The gateway detects an eliminated error automatically after commissioning the repaired device and resets the error state in the feedback.

1-byte error status
Bits 0...5 of the 1-byte error status telegram use the electronic ballast number to indicate to which device the signalled error relates. The electronic ballast numbers of the error status are derived directly from the short addresses of the DALI subscribers. An electronic ballast number (0...63) corresponds to a short address (1...64) minus "1" (example: Short address = "1" -> Electronic ballast number in the error status telegram = "0").

When an error status is displayed, it is irrelevant whether the electronic ballast was assigned to a single device or a group during project design.

Bit 6 is set when the appropriate electronic ballast signals a lamp error (e.g. defective lamp, cable break to lamp socket). In an error-free lamp state, this bit is deleted ("0").
Bit 7 is set when the electronic ballast signals a general error (e.g. internal electronic ballast error). In an error-free device state, this bit is deleted ("0"). Bit 7 is also set if the appropriate device could not be addressed by the gateway (e. g. device disconnected from the DALI cable, mains voltage at the electronic ballast switched off).

2-byte error status
In this data format too, bits 0...5 use the electronic ballast number to indicate to which device the signalled error relates. The electronic ballast numbers of the error status are derived directly from the short addresses of the DALI subscribers. An electronic ballast number (0...63) corresponds to a short address (1...64) minus "1" (example: Short address = "1" -> Electronic ballast number in the error status telegram = "0").
Alternatively, the 2-byte error status can be used to display the collective error state of all the operating devices of a group. For this, the error-bits of the individual electronic ballast are collected and evaluated by the gateway. If any error bit is set in at least one electronic ballast of the group, the same error bit is also set in the feedback telegram.
To distinguish whether the feedback is addressing an electronic ballast or a group, the error status telegram contains bit 6. This bit indicates whether a single device ("0") or a group ("1") is addressed. When addressing a group, bits 0...5 must contain the group number in the DALI system. A DALI group number (0...15) corresponds to a projected group number (1...16) minus "1" (example: projected group number = "1" -> DALI group number in error status telegram = "0").

Bit 7 in the telegram indicates whether this is a request telegram ("1") or, alternatively, an actively transmitted telegram, or an answer to a request telegram ("0").

When the error status of an electronic ballast is displayed, it is irrelevant whether the operating device was assigned to a single device or a group in the project design. In the case of active telegram transmission, if an error has been identified, only the error status for an individual electronic ballast is generally transmitted and not for a group, provided that the appropriate electronic ballast is also assigned to a group.

Bit 8 is set when the appropriate electronic ballast or the group signals a lamp error (e.g. defective light, cable break to lamp socket). In an error-free lamp state, this bit is deleted ("0").
Bit 9 is set when the electronic ballast or the group signals a general error (e.g. internal electronic ballast error). In an error-free device state, this bit is deleted ("0").
Bits 9 is also set if the appropriate device or an electronic ballast of a group could not be addressed by the gateway (e. g. device disconnected from the DALI cable, mains voltage at the electronic ballast switched off).

Setting the error status per DALI operating device

It must first be defined whether the 1-byte or 2-byte error status is used, or a combination of both objects.

Optionally, a delay of the error status after initialisation of the gateway (ETS programming operation, mains voltage return) can be activated by the parameter "Delay after mains voltage return and ETS programming operation". The delay is configured globally on the same parameter page by the parameter "Delay after bus/mains voltage return".

The error status per DALI operating device can be used as an actively transmitting status object or additionally also as a status object that reacts to an external request telegram.

In the case of active telegram transmission, if an error has been identified, only the error status for an individual electronic ballast is generally transmitted and not for a group, provided that the appropriate electronic ballast is also assigned to a group.

An error saved in the gateway is lost when the mains voltage fails. For this reason, after an error has been eliminated by switching the mains voltage off and back on again at the gateway, no feedback is transmitted any more.

The gateway initialises after switching on the mains power supply or after an ETS programming operation. If a DALI error is detected in this state, the gateway will immediately transmit an appropriate feedback telegram.

Request telegrams to electronic ballast or group numbers, which are not configured in the DALI system and are thus not available, are always answered with deleted error-bits. Request telegrams to group numbers greater than 15 (group number greater than 16) are never answered.

A read telegram (ValueRead) on the communication object "Status - Error status - Operating device" is answered by the gateway transmitting the most recently updated object value provided the read flag is set (ValueResponse). This means that DALI operating devices cannot be polled clearly.

Error status per DALI group / single device

In addition to signalling a general DALI error status in the DALI system and the individual feedback of the error status of a DALI operating devices by means of the 1-byte and 2-byte communication objects, the gateway also enables the indication of an error status identified in a projected group or single device. All error status functions can be used simultaneously.

The error status per DALI group / single device has a 1-bit communication object "Error - Status" for each projected group and each single device, which allows an error to be indicated directly in the group or at the single device. The gateway sets the object value to "ON" as soon as it detects an error. Here, it is irrelevant which error was identified by the gateway (lamp error, electronic ballast error). The gateway does not reset the object value to "OFF" until the previously identified error has been eliminated.

To use the status function, the parameter "Error per DALI group/single device" must be set on the parameter page "DALI System... -> General" be activated. When the function is activated, the parameter "Telegram repetition on new error" is available for each group and single device on the parameter page "DALI system... -> Configuration groups -> [x] Group name" or "DALI system... -> Configuration single devices -> [x] Device name", which determines whether status telegrams are repeatedly generated if several errors occur in succession.

Setting the error status per DALI group / single device

The error status per DALI group / single device is implemented as an active signalling object. The gateway automatically transmits the status to the KNX with every change.

An error status saved in the gateway per DALI group / single device is lost if the mains voltage fails. For this reason, after all the errors have been eliminated by switching the mains voltage off and on again at the gateway, no status is transmitted any more.

The gateway initialises after switching on the mains power supply or after an ETS programming operation. If a DALI error is detected in this state, the gateway also transmits an appropriate status telegram. After the bus voltage returns (mains voltage switched on permanently at the gateway during a bus failure), the feedback is not automatically sent to the KNX.

Optionally, the error status per DALI group / single device can be transmitted repeatedly if further errors are detected after a previously identified DALI error. The parameter "Telegram repetition on new error" on the parameter page "DALI system... -> Configuration groups -> [x] Group name" or "DALI system... -> Configuration single devices -> [x] Device name" defines the behaviour of the general error status in the event of new errors.