This note describes how Artistic Licence products can handle a sudden loss of data.
The term ‘fail-over’ has a subtly different meaning depending on the circumstances. The key difference is whether one looks at the situation from the perspective of the controller or the receiver. But in either case, the important consideration is that the lights go to a known condition when DMX512 data loss occurs.
The majority of Artistic Licence receivers, such as sunDial, candlePower and Rail-Switch have the ability to detect loss of DMX and take action. The action can be to ‘hold last state’ which is the default for DMX512 equipment, or playback a preset scene. These features are all programmed via RDM (Remote Device Management).
Dealing with a controller failure requires a combination of products to detect the fault and then take action. There are two key approaches: merge and switch.
DMX mergers such a Rail-Merge and matisse f6 have the ability to hold last state. This means that if the DMX512 control signal is lost, they will keep outputting the last signal they received. This approach is useful in some circumstances but lacks flexibility.
Fail-over is further complicated when multiple universes need to be protected. Rail-Flip can protect four universes of DMX512. In automatic mode, it monitors the inputs and if it detects a loss of signal on any of the A-inputs, it will switch to the B-input. Additionally, the product uses relays to do the switching, so it also protects against power loss.
In this approach, fail-over switches to a second DMX controller, such as a matisse f6.
Gateways convert ethernet Art-Net or sACN to DMX512/RDM. So what happens if the ethernet control signal is lost? The premium range gateways such as dataLynx, netLynx and artLynx quad have fail-over detection. This means that you can program what the gateway should do in the event of network failure. The action can be to ‘hold last state’ which is the default, or playback a preset scene. These features are all programmed via DMX-Workshop or the gateway’s web browser.
Application Note 0201 – DMX & RDM Introduction. This includes wiring details for XLR and RJ45.
Application Note 0205 – DMX & RDM Splitters. What are they and where to use them.
Application Note 0215 – DMX & RDM Marking. Howe to interpret splitter marking symbols.
Application Note 0210 – DMX & RDM Splitter Comparison. Compare Artistic Licence splitters.
Q: What is maximum cable length for DMX512?
Q: Can I use Cat5?
Q: How do I terminate:
A: With products that use an XLR, you can connect a terminator plug. With DIN-Rail products, there is an internal terminator which is connected enabled by fitting a wire link between TERM and DATA+.
Power-over-Ethernet or PoE defines the way that an ethernet cable can be used to send both power and data to a product. The product which uses PoE is called a ‘PD’ (Powered Device) and the product which supplies the power and data – often an ethernet switch – is called the ‘PSE’ (Power Sourcing Equipment).
PDs require differing amounts of power depending upon their design and the load they are driving.
PSEs are capable of supplying different amounts of power.
These variables are addressed by a number of IEEE standards:
- PoE is described by IEEE802.3af-2003. It allows a maximum of 15.4W to be supplied.
- PoE+ is described by IEEE802.3at-2009. It allows a maximum of 25.5W to be supplied.
- PoE++ is in development and will be described by IEEE802.3bt-2017. It allows a maximum of 90W to be supplied using all 4 pairs. There are 4 different power levels available: 38.7W, 52.7W, 70W and 90W.
The wattages described above refer to the power made available by the PSE. As there are significant losses in the cable, the amount of power available at the PD is lower.
After Windows XP, Microsoft significantly changed the way in which application software can communicate with Windows. This means that in Vista, Windows 7, 8 and 10 some of our software products must be run in a special mode. This mode is called Windows XP compatibility mode with administrator rights. See the application note.
The product concerned is Mic-Edit.
There are three key methods of dimming LED: mains, constant current (CC) and constant voltage (CV) .
- Mains dimmers are used with LED replacement bulbs.
- CC dimmers put out a controlled current, which means that the fixture does not need electronics for current control of the LED. This style of dimming is used for higher power LED products.
- CV dimmers put out a constant voltage and the current control is done by the LED fixture. This type of dimming tends to be used for the lower power LED products such flexible tape.
It is important to choose the correct technology of dimmer as an incorrect choice will most likely damage the fixture. Below is a summary of the dimmers offered by Artistic Licence:
sunDial quad is DMX512/RDM controlled 4-channel, mains powered trailing edge dimmer. 1kW total at 230 VAC.
Constant current or constant voltage
candlePower octo is a DMX512/RDM controlled LED dimmer with 8 channels. Each channel can be individually set to constant current (CC) or constant voltage (CV) dimming.
- Voltage: 10-60VDC
- Current Max: 2A per channel
- Control: DMX512 / RDM
- Form: DIN Rail
Constant voltage only
Rail-Pipe HC is a high current DMX dimmer for 2 x RGB circuits (6 channel).
- Voltage: 12-24VDC
- Current Max: 20A per product, 10A per RGB circuit
- Control: DMX512 / RDM
- Form: DIN Rail
Artistic Licence offers a broad range of DALI products.
There is a very large speed difference between DMX512 and DALI, which means that care must be taken when designing a lighting installation that uses both protocols. Artistic Licence has prepared The DALI Guide (see below) to assist all DALI users and installers, particularly those who are more familiar working with DMX512.