Our controller will regular poll the lights status for these failures and report back on the cloud.
These faults are exclusively reported by the driver / ballast and are not created by the control system. The control system is simply querying and reporting the information from the driver/ballast.
These issues are seen in the Device Location Section
An example of these issues:
A lamp failure may indicate that a lamp has indeed failed / is close to failing and needs replacing or that the ballast has experienced an issue that may need resolving (an example would be an unsupported lamp).
If the device is not an emergency device, control gear failure is a manufacturer designated fault and may be due to adverse conditions/functionality/setup.
Both of these issues are reported by the dali command QUERY STATUS. The device is required to report back arc level 255 for actual level in this situation. This arc level cannot be requested by the controller.
It should be noted that if the device is an emergency device, the same above conditions apply as well as the additional condition that control gear failure is required to be set if a function or duration test is failed. In the cause of a duration test, this may be as simple as that the battery is not fully charged or reaching its end of service life. A function test may fail due to missing lamp or other manufacturer designed failure conditions.
The controller does not have the capacity to set these failures, nor is there a command that should cause these bits to be set. The dali standards do not allow for dangerous commands that could cause these states.
Possible sources
In our experience, such failures can come from:
- Bad/unsupported lamp fixture
- Incorrect configuration (check dip switches on device if present)
- Wiring
- Adverse conditions (undervoltage, overvoltage, thermal shutdown)
- Defective hardware
- Firmware issues in the driver/ballast (bugs)
- Other unknown issue with the driver/ballast
Diagnosis
It must be strongly noted that this failure is either a real failure on the device or a failure with the device (driver/control gear) to detect and report the error correctly. In these cases, if the configuration and setup of the device is correct, the driver/control gear manufacturer may be the only party that is able to rectify the issue.
If the issue is intermittent and the light is otherwise functional, it may indicate that the parameters governing whether a lamp has failed may be too stringent on the device.
If the issue persists and the worse still, the light is found to be now at an incorrect level or off, further investigation will be necessary.
The most basic test would be to reset the power to the device and monitor whether the failure is present on startup. If the failure is not present on startup, leave a dali monitor running on the controller to try to witness the transition into the failure state and establish what conditions are in play when the light is first found to be lamp failure. IE, were the lights just turned on/off? Had they been off for a large amount of time?
If possible, set the power on and system failure levels to unique values (ie, 253, 252) so that it can be easily discerned if a light has failed to a specific value. Note that if the power on level is set to a non "last level" value, any interrupt of power could potentially light up an entire building.
Further Technical Investigation
If you wish to verify for yourself that the failure is present, see the frequent polls of QUERY STATUS in the monitor
In the case above, the answers are decimal 11 (hexadecimal 0xB).
Bits 0, 1 and 3 are set. Bit 0 = Control Gear Failure, Bit 1 = Lamp Failure, Bit 3 = Limit error (the ballast has set its actual level to 255 which is an error state and above the max level of 254).
You may also see "ELM Mismatches" where the Expected Lighting Module reports when a light is not at the expected value it was previously set to
In this case, the device has set its ACTUAL LEVEL to 255 which is in an error state that cannot be set by any external device. Sending ARC power 255 does not send a device to arc level 255. It stops an active fade.
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