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Microphonics™ – Thats not a word!

admin on June 26, 2009

Microphonics™ isn’t a word is it? It is now!

Microphonics

As those of you who know me will be aware I am a big fan of Automation. The use of sensors in control systems is the clever and progressive way forward.

Putting light switches when they are not the best solution is a waste of money, time and energy. However specifiers and installers are still scared of occupancy sensors.

They are scared of the call-out when Mr Client has been plunged into darkness while reading his paper in “The Library”.

This has been a real problem and often the only way to counter the problem is to up the time delay off to a sufficient level that we are confident that a traditional good quality PIR occupancy will re-trigger the time delay off.

This of course is not an ideal solution as we end up having lights and fans on burning energy for longer than we should have.

Some companies looked at gate sensors systems by which a control system could monitor a person entering and leaving a space and combine these with a PIR to get a more accurate result. These systems have a number of limitations including the problems cause by multiple users and high cost due to the requirement for multiple sensors.

Sensor Switch have produced a dual technology sensor which combines a PIR detector with a high gain microphone and some clever audio processing to achieve a good result.

Motion is first detected by the PIR and the the microphone is switched on to listen for continued occupancy.

The system filters out repetitive noises such as plumbing and HVAC sounds to allow the sensor just to trigger from sudden noise changes such as created by a user.

I will be very interested to find out how well the unit deals with background music!

Lighting Control showing the colours

admin on May 3, 2009

Colourstyle1

Lighting controls were showing the colourstyle controller at the recent Bar 09 Show at The highland Showground in Edinburgh.

The Colourstyle controller is the perfect controller for back bar effect lighting. The controller allows complex colour effects to be setup using the setup wizard and then provides a very usable interface for day to day use.

The system can also be programmed with timed rules to allow automation.

DMX Architecture Were here to help!

admin on April 6, 2009

DMX as a standard was developed for the entertainment industry and has been adopted for use in large architectural projects over the last few years.

Lot of articles on the internet cover the electronic details of what DMX is which is of interest to those wishing to create products that send or receive and wish to comply to the standard. This is of no interest to lighting designers and electrical contractors. The architecture of a DMX control system is governed by the other side of the standard EIA485 this describes the electrical system that DMX uses as it’s bedrock. This is the roadway that the communication runs on; if this underlying infrastructure is not correct then the communications trying to use it will falter and the system will never be stable and reliable.

DMX Standard was originally adopted for use by “lampys” at touring events where large entertainment systems are setup up for a show or a series of shows before being all packed up into a number of trucks and moved to the next show.

Power distribution for these shows is all done using flexible rubber cable and Ceeform cables connecting different parts of the systems using portable distribution units. The construction industry has a more cost effective and longer lasting method using steel wire armour and fixed distribution boards around a project.

The distribution for a project is designed in a drawing office by an electrical engineer.

Power Distribution Drawing

The engineer designs the system by completing calculations and specifying suitable cabling and distribution panels to ensure that the system will work correctly and safely.

DMX is used by the construction industry primarily to control colour change lighting. By it’s nature a single colour change unit uses three or four channels of DMX and puts a unit load on the DMX controller of the system.

In the same way as the electrical distribution example above DMX requires design. It’s a simple thing to say but frequently the architecture of a DMX system is left to chance. When a ring main is required in a electrical system often the exact numbers of outlets and types of outlets will not be specified or indeed if a small change is required then the installing electrician will make the design change in a flash. This is simple as a the architecture (limits on length, number of outlets, spurs) is well known by that electrician through years of installing these simple systems.

DMX is a simple architecture however colour change systems can use a large number of DMX recievers and control channels. In addition to this systems should be designed to allow section testing by isolation and also to ensure downtime in certain areas of the system will not affect control over other parts of the system.

Simple DMX systems have a single cable connecting a number of fittings allowing a controller to control attributes on all these fittings independently. In reality all but the most basic DMX systems require boosters, splitters and termination to allow a stable system to exist and to ensure minimum installation time.

DMX is a not a proprietary control standard it is used by countless manufacturers and the size and complexity of DMX control required in a project is on the increase all the time.

So don’t chance it ! Were here to help!

The DMX 512-A Handbook

Save energy with Lighting control systems

admin on March 27, 2009

Energy saving light bulbs have taken over the world in the last couple of years so much so that later this year (2009) the major retailers in the UK plan to remove filament light bulbs from there shelves.

However in most projects with lighting controls low energy light bulbs are not to be found. In fact most systems do not support them.

Dimmable energy saving light bulbs are still in the early days of development and are not yet as cost effective as their non-dimmable predecessors.

Lighting control systems can however give significant energy savings.

Control empowers correct usage of multiple fittings. With more circuits to control only the lighting that you need for a task need be turned on saving 100% on lighting that is not required.
Off during non-activity: Using timed off’s and proximity sensors in a lighting control system we can ensures that lights are not left on when the need not be.
Daylight harvesting: Daylight harvesting allows lights to be automatically dimmed to a level dependant on the amount of natural light reaching the target area. This saves in energy usage as the quantity of additional lighting used is limited to what is required exactly.
Dimming at full power: Not running lamps at 100% can result in massive extension of lamp life.

Mode Lighting and the 17th edition

admin on March 27, 2009

The recent introduction of the 17th edition regulations means a number of changes in the protection of circuits.

Mode Lighting units such as the tiger and Evolution have no main isolator and hence even in the previous edition of the regulations a mechanical isolator was required to isolate the incoming power to the unit to carry out mechanical and electronic maintenance.

The best solution seems to be three independent RCBo’s mounted in an external housing local to the Evolution control pack.

1 RCBO for each phase/bank of breakers – this requires that the pack neutrals are split for each RCBO and that the pack power supply (3 phase + neutral connection) is rewired to the mains supply side of the RCBOs. A warning label should be applied to the pack to this effect.

If a single phase supply is used for Evo/Tiger, it becomes easier, in that assuming RCBOs are only needed for one or two of the banks of breakers, the PSU can be powered from the remaining bank (ie all 3 PSU live inputs can be connected to the bottom of one set of breakers).

In all cases, it is essential that the load live and neutral outputs are connected to the relevant set of outputs, otherwise the resultant imbalance will cause tripping.

If you need advice on design or installation of a lighting control system please contact us and we can look over your project and ensure it meets all the current standards.

RS232 handshaking for the non-technical user

admin on March 8, 2009

A recent project meant i had to explain a RS232 integration to non technical users.

RS232 is a very simple way of communicating between two systems.

You can think of it as a simple speech communication a good example being the exchanges of speech that go on in a parliment or any sort of debate.

Members of parliment wish to speak to the house but if they all speak together then the message will be lost or confused due to the inability to hear the different messages coming from each parlimentarian.

To solve this problem RS232 has hardware flow control or handshaking.

When each member of the house has a message they stand and raise there hand to say that they are ready to speak. The speaker of the house then indicates to one member that the house is ready to hear their message and in this way one message at a time is heard.

In an RS232 system only one line of communication is established. Imagine a secretary and her boss dicatating a letter but the secretary has no short hand skills. Each small section of the letter dicatated by the boss is brought to an eand by the Secretarty saying “STOP” while she finishes writing that section on the word processor. When the secretary is ready to continue she indicates this to the boss and the next section .

In the RS232 system these “STOP” and “GO” messages are indicated by the high or low level of the CTS flag. The sending system has a similar flag (RTS) which indicates that it has data ready to send to the recipient.

	9 Pin Connector on a DTE device (PC connection)
Male RS232 DB9
Pin Number	Direction of signal:
1	Carrier Detect (CD) (from DCE) Incoming signal from a modem
2	Received Data (RD) Incoming Data from a DCE
3	Transmitted Data (TD) Outgoing Data to a DCE
4	Data Terminal Ready (DTR) Outgoing handshaking signal
5	Signal Ground Common reference voltage
6	Data Set Ready (DSR) Incoming handshaking signal
7	Request To Send (RTS) Outgoing flow control signal
8	Clear To Send (CTS) Incoming flow control signal
9	Ring Indicator (RI) (from DCE) Incoming signal from a modem

Manual Control of Automation

admin on March 8, 2009

Automation is great and sales people sell lighting control systems based on the ability to automate tasks.

But as anyone who sets a daily alarm knows automation is not great when the alarm wakes you up on a Saturday morning instead of allowing you your well deserved lie in!

This is a very simple example of how automation requires a really well thought out quality specification. When setting the alarm the simple choice is to tick the “every day of the week” !

When doing lighting controls a basic automation requirement is that lights turn off automatically after all staff have left the premisis. This ensures that if lights are left on they will not stay on all night which saves on lamps and energy costs.

However on special occasions for example the christmas party the premisis is to be used after closing to host the party or on a special corporate launch night you invite your major client to a reception to lanuch your latest new product.

The presentation is then cut abruptly short as the lights dim to zero. At best this causes inconvinience and at worst can present a real health and safety problem as people are literaly left in the dark.

I remember an example of this would happen each year at our local church. The exterior of the building is floodlit by the local council controlled from a timer control located in a panel outside the church. Each Christmas the midnight service to bring in Christmas day would take place at 10:30pm and church-goers would be able to find there way around the church from the light of the floodlights. However on Christmas morning the lights would turn off at 12:30 am meaning that we would exit the church to darkness!

The simple solution has been provided in HVAC systems for many years. A three position switch on a panel allow selection of “OFF” , “ON” and “AUTO”. This allows the system to be forced off , forced on and forced to do whatever it is supposed to do depending on any automation that has been programmed into the system.

This is a really simple local overide that works and should be used as a starting point for local overide.

However our automatic specification was written to stop somebody leaving the lights on overnight. This local overide gives them exaclty this power again so we have failed to meet the specification.

Another heating control analogy is the “+1h” button or “Next Step” button often found on simple heating controllers this enables the users to slightly atler the auto mation by telling the system that for the next hour it is one hour ahead of the real time (allowing you to turn on or off the heating early) or to tell the system that for the rest iof this period of automation you want the system to do the functionality of the next period of automation.

This is better as the period of non-automation is restricted if you like the automation is automatically switched back on!

There are many methods of solving this problem and unfortunately often the problem is solved by removing the automation due to the fear of an un suspected turn off.

With good design features of lighting controls systems can be fully utilised and not hindered.

Lighting up the Poles in Glasgow!

admin on March 6, 2009

The market leading gentlemen’s is opening in Glasgow in the west of Scotland and Lighting control were on hand to renovate some existing lighting controls for the project.

Dedicated to offering top class entertainment in a relaxed and welcoming atmosphere, Spearmint Rhino has exceptional clubs throughout the UK.

Spearmint Rhino

Ellersly House Lit up in Edinburgh

admin on March 6, 2009

Lighting control have completed yet another high quality residential project using the Mode evolution systems of lighting controls.

Ellersly House

Dan Aberdeen completed design and commisioning of scene control and whole house control for a local Edinburgh Developer.

The commisioning is the second of a number of properties to be completed in the same development.

1-10v Lighting Control Installations whats the standard?

admin on October 2, 2008

1-10V

A recent project highlighted the common mistakes made when wiring 1-10v DC analogue control.

When wiring for DMX or Dali there is a widely accepted standard which can be followed but with 1-10v control there is no such standard I guess the thought is always but it’s so simple how can it go wrong!

The Basics:

Electronic ballasts display a 10V DC between there 0V and + control inputs. When this connection is open circuit the ballast provides full brightness on its connected lamps.

A controller sinks current to reduce this control voltage to 1V to achieve maximum dimming (lowest brightness).

The Simple Test:

Short the + and 0V connected to one or a number of ballasts in parallel and ensure that the connected lamps dim to the lowest dimming level. On removing the connection the lamps should return to 100% brightness.

A more advanced tests:

Ballast / group of ballast test:

Using a DC ammeter the current required to reduce the control voltage can be checked. The current is noted in the specification for all ballasts and is generally less than 1mA. If a ballast is producing a higher current then it may be faulty.

Controller Test:

To check, connect the controller, set to lowest brightness and measure the voltage on the control line. The value

should be 1 V or less.

These golden rules should be followed by specifiers and installers to ensure the best operation of these types of systems:

1-10v Golden Rules:

Study product data sheets, installation instructions, and specification guides and/or handbooks carefully before designing and applying one of the various control systems.
Check carefully the needs, wishes and expectations of the customers and users with the possibilities of the preferred or applied control system.
Ensure that sufﬁcient knowledge of the control system is available on the side of the contractor. Education possibilities should be available.
Mark cabling at beginning and end. Use the correct cabling within the maximum lengths.
The control line is isolated from the power line but not at safety extra-low

voltage (SELV). Cables and terminals that are approved for 230 V must

therefore be used.
Avoid humidity and temperature shocks for the electronic components during installation.
Connect dimlines according polarity: plus to plus and minus to minus.7) Treat dimline wiring like mains voltage wiring.
Check that the working of the lighting installation is 100 per cent correct before connecting or commissioning the control system. It is advised to let the installation run for 24 hours before commissioning. We recommend that you allow new lamps to burn in for at least 50 hours at 100% luminous flux.
Be careful during the insulation tests (when using mega ohmmeter).
Carefully check the wiring and connections of the control part before starting with the conﬁguration / commissioning.
Make proper earth connections for the metal optics.
The routing of cabling should ensure that neither the mains power supply cable nor the control cable runs parallel to the output cables from the ballast as these operate at high frequency and may cause interference.
See manufacturers specifications for cable type but our recommendation is a minimum cross section of 0.5mm2