The K15 is a sensor with its own microprocessor, in addition to its infrared sensor and photo sensors, with the ability for delayed auto off, it also has the capability for vacancy mode and occupancy mode; it can also be used in conjunction with classic wall switches through its dry contact input. The output of the K15 is can be connected to an ac power source so that it can be used to directly control the lights, or it can be used connected to the dry contact DI of another device. The vacancy and occupancy modes of operation are introduced below.
K15 Occupancy Mode
The occupancy mode is most often used in places that are high traffic areas, such as restrooms, hallways, pantries, storerooms and so on. The basic operation is people come, lights turn on; people leave, lights turn off. But manual operation can also be used to turn the lights on or off in advance.
The Purpose of the Manual Switch
- Turn the lights off manually before the auto delay off kicks in.
- Augment the blind spot of the sensor, enabling the lights to still be turned on manually when needed.
- For the purpose of saving energy, the photo sensitivity is set to its lowest level, at this time, even though it has detected the occupant, it still won’t turn the lights on. However, when there is a special event, a long button press can activate the prolonged on mode which allows the light to remain on indefinitely up until it is turned off manually (at this time, the sensors are ignored).
- The push button switches are low voltage switches, and thus there is little danger of current leakage.
K15 Vacancy Mode
The vacancy mode is most often used in places of work, such as small offices, labs, lounges, meeting rooms, workshops and so on. In the past, these places would have classic rocker switches, but the problem with these is that when the occupant leaves, they often forget to turn the lights off which leads to wasted energy. The K15 in conjunction with push button switches can effectively reduce wasted energy.
- The lights need to be turned on manually.
- The lights can be turned off manually, but if the occupant leaves and forgets to turn the lights off, the sensor will detect that the occupant has left and will turn the lights off automatically.
- There are times when the lights need to be turned off even there are occupants, such as when the projector screen is being used, in which case the lights can forcibly be turned off.
The Purpose of the Manual Switch
- For use within the room to manually turn the lights on and off, the sensor is used only as a backup to turn off the lights in case the user forgets after they leave.
- As much as possible, when leaving the room, the lights should still be turned off manually, and one shouldn’t depend on the sensor to activate the delayed auto off.
- Since the push button is low voltage, then there is little danger of electric shock from leakage currents.
- Even when the power is supplied, the lights will still not turn on, it will only turn on when the button is pressed. This behavior is different from regular wall switches.
The LT3000/LT3384 can be connected to classic switches for the multiple access and can also be used for delayed auto off, group control, and pattern control; and they can also be used for schedule control and sensor control.
- Multiple access for hallways and warehouses
Multiple classic push button switches are installed along the length of the hallway to allow for multiple access.
This is applicable not just for hallways but can be used for stairwells. Nowadays, the stairs are used less often as people tend to prefer the elevators, as such stairwell lights should only be turned on when people are using them.
All the lights in the stairwell would be divided into circuits consisting of 5 floors each. Each of these five floors would have push button switches installed along their entrances which are connected in parallel. The switches are connected to the LT3000 input terminal, which allows the switches to control the lights indirectly through the LT3000. This will allow the group of lights to be controlled from any of these switches. In addition, the building manager can also monitor and control the same lighting circuit remotely through the IS45 or from a touch panel.
- Daylit hallways and restrooms
During the day, it is desirable that the lights are restricted from being turned on, and only at night would they be allowed to be free to use. How can this be achieved?
In order to achieve this, the LT3384 is used at the local site, the LT3384 has a special feature that allows its channels to be either forced on/off or authorized.
When the lights are forcibly being turned either on or off, then the local switches are disallowed from being used, but
- Split type airconditioning
There are many classrooms and offices that make use of split type air conditioning and the building administrator would desire that there would be some way to save energy from them as well. If the LT3000 is used, then one can choose to have a manual switch included or not, either way will work.
- Method 1: Equal Access
There would be an LT3000 installed locally with a local manual switch, the building manager would have a touch panel.
The air conditioning can be controlled locally as desired by the user. The building manager could turn off all the air conditioning after classes or work. If some is working overtime, they can still turn the air conditioning back on as needed. This is a kind of soft central control whereby local control is given as much leeway as possible, but still allow for energy saving to be achieved.
- Method 2: Central Only
Locally the LT3604 would be used, but there would be no local switches, control would be exclusive to central control.
This way, the air conditioning can only be turned on from the control center.
- Method 3: Authorization
Just like in method 1, central control turns off all the air conditioning after classes and work hours. Then it can be decided whether or not to allow local control. If allowed, then the local user can turn the air conditioning on if they wanted to.
Pattern switches would be installed near the entrance, every section would have LT modules installed.
- The pattern control capability of the LT3000 could be used to match the routine; a button press could instruct all the lights in the area to turn on during office; another button press after office would then turn off a portion of the lights, while the last person to leave would press the “all off” button to turn off all the lights.
- Small private offices, showrooms, storerooms, meeting rooms and other small rooms, are places that are not always in use. Each of these rooms would have a set of switches connected to the LT3000 which would allow the user to control the lights as desired. When the user leaves, a single button press at the entrance would then turn off all the lights in the room.
A public lighting control system should be combined with the safety system into a single unified system.
Public lighting control and safety systems pretty much uses the same type of controllers and signal cabling, and are quite compatible. Both of these systems are actually quite dependent on the bus line for for control, the SLCS has combined both of these systems into one. They share the both terminal unit, the same bus, and even the same sensors. This way, an even greater cost savings can be attained during construction, even the central host can be shared.
There are 5 different types:
- Responsive System
One of the unique features of architecture of a lighting control system is that it has a fast response, a button press will immediately elicit a response from the lighting that it controls, this feature is similar to the safety system. Once the safety system detects an alarm signal, it will immediately alert the control center, this is one reason why these two systems are very compatible.
- Shared I/O Modules
The LT3000 and the LT3384 modules of the D-Bus system are the most commonly used models in a public space. Both of these model have input signal ports, and input ports even outnumber the output ports. Thus, most of the time there would be extra input ports that are left unused, when used in combination with some other modules, these ports are just right for use by the safety alarm signals. Coincidently, both these systems are for use in pretty much the same living space and can thus can even share the bus wiring.
- Shared Sensors
The sensors used for the safety alarms are widely spread out, each floor requires them, but they are not numerous, and they include infrared sensors, escape door reed switch, emergency button in bathrooms and fire alarm switches. The use of these sensors may overlap those of the lighting control system, such as the infrared sensor for example, which can be used for the safety alarm system or as the motion control sensor in a lighting control system. When a fire alarm does occur, not only is the safety alarm system alerted, but it could also be activate the emergency evacuation lights.
The emergency help button, can be monitored for safety, but can also be used to activate the lights and sound the loudspeaker.
- Good Integration With The Central Host
Even with the control center, there is overlap. Both the lighting and safety alarm systems make use of the floor or elevation diagram, if both of these systems are combined into one, not only will it save on costs but at the same time they can share the same diagram for both monitoring and control, everything is more efficient and effective.
- For the security post, a simpler touch panel could be used
The safety alarm system, other than having to provide feedback to the control center, should also do the same for the security desk, allowing them both to keep track of the real time status of the system.
If the multiple access capability of the smart lighting control system is applied to the safety alarm system then the end result would even be better. This is achieved simply by having the host computer be in the control room, and a touch panel be at the security post. This particular advantage, as compared to before when no touch panel is installed makes the system more practical and increases the cost effectiveness of the system even more so.
- Incandescent bulb and halogen lamp
These types of light can basically be dimmed using triacs. The dimming response curve is quite smooth and very apparent. But since incandescent lamps are being phased out by law, most of these are being replaced instead by CFL, whilst halogen lamps will be replaced by LED lamps.
- Fluorescent lights
These are very common and can be found in a plethora of places such as offices, retail stores, factory floors, classrooms and many other public places.
Rarely are they found as dimmable lights, and they being replaced by T5/T8 energy saving fluorescents, and also being replaced by LED fluorescents.
T5/T8 fluorescents can be dimmed using electronic dimming ballasts, the most common type are those adjustable from 0 to 10V, often these types of ballasts will not turn off completely even at 0V, and a faint glow will still be visible. If one wants to truly have the lights off, then a switch is still needed to completely cut of the power.
Fluorescent lights that are dimmable in this manner is very rare, and even when present, their main purpose is to save energy and not for use as mood lighting.
- CFL – Energy Efficient Compact Fluorescent Lamps
These are commonly found in residences, and used to replace traditional incandescent lights, they are not very rarely used in dimming applications, but still they do exist, and the method used is by using triacs. Situations like this require that the CFL type specifically be marked as being “dimmable”. Otherwise, using a triac is not guaranteed to be able to dim the lamp.
In practice, the dimming effect is quite weak, and at low levels, the light will flicker. When dimmed to its lowest level, it will turn off completely.
Of course, having this dimming capability versus one without will increase its costs quite significantly.
- LED lamps
These are used to replace all sorts of traditional lamps including incandescents, fluorescents and halogens; and may even replace strip lights and mercury lights (street lights, park lights). The form that LED lamps can take are innumerable and they come in all shapes, sizes and color temperatures. They have a wide variety of power supplies (a/c, a/c dimmable, d/c constant current, d/c constant voltage, d/c constant current dimmable, d/c PWM dimmable); and they need to come with a wide range of wattages and d/c voltages. Some have the power supply built in (outwardly appearing as a/c), while others require an external power supply, and some emphasize that they are dimmable, or there may be any number of combinations of the above. Faced with such a multitude of possible choices, making sure that one obtains one that is dimmable and the matching type of dimming power supply becomes a job for an expert.
Purely from the point of view of control, one type is a/c dimmable using a triac, while the other is 0 to 10 VDC. Each requires the appropriate type of lighting controller, as these are very different technologies.
With dimming, the emphasis may be for mood creation, or it can be mainly to save on energy.
As can be surmised from the above, when dimming is desired, selecting the right type of lamp is the first step, and the second step is a matching dimming driver, the third step is to get a controller that will work with the driver. If a non dimmable lamp is used, then no dimming is possible even if both the power supply/driver and controller having dimmable features.
What venues are suited for dimming?
- For setting the ambience such as the chandelier of a great hall. The numerous smaller lights use energy saving lamps which are on/off controlled only.
- Also for setting the ambience. The lights are meant to either be fully on or off, but with the capability to switch the lights by a gradual transition instead of an abrupt change, the purpose of which is also to create a more elegant and classy atmosphere. Halogen lamps are mostly used in this situation, if LED lamps are used instead then the cost increases substantially.
- Energy saving fluorescent lighting: Fluorescent lighting for large spaces, sometimes of the LED type, which require different lighting levels at different times to save on energy.
During office hours for a large office, the sensors in any given section will turn on the lights for the duration of the office period (except for the private offices, meetings rooms, reception rooms).
The other private offices would have wall switches. Each section of a large office would have its own infrared sensor to monitor that section, the sensor would be connected to the LT3384 to control the lighting needs for that section. IS45 digital switches would be installed near the entry area for use during overtime, and also for the “all off” button.
Kitchens, copy rooms, and other special purpose small rooms would have their own infrared sensors to control their lighting.
- Open offices
- During office hours, every section would have its own sensor which will turn on the lights when an occupant is detected.
- After office hours and people begin to leave, the sensor would turn the lights off after 10 minutes in its section when it no longer detects any movement in that section.
- If there is someone left in the office working overtime, that person can go to the digital switch for their section and press the section button to allow the lights in their section to remain on and disregard the sensor. When the person leaves, they can simply press the button again to turn off all the lights in the office. (Note: the LT3384 should be set to forced-on mode).
- Small offices, reception rooms, meeting rooms
These rooms can make use of the K24. When someone enters, they can turn the lights on manually using the classic wall switch. When they leave, they can turn the lights off manually from the same switch, or if they forget, the lights will be automatically turned off after a certain delay.
To create the desired atmosphere, the lights would be finely divided into multiple circuits so that the lighting combination can be varied to create the desired effect. The lights are normally set low, but when a customer comes, the appropriate pattern is then activated to highlight the item being viewed to highlight it. Once the viewing is finished, the lights are set back to normal.
- Kitchenette, copy room, filing room, restrooms
May make use of the K24 sensor operating in delay mode.
- Conference Halls
Before the start of the conference, the lights and air conditioning is set to a basic level from the operator booth to a level comfortable to the audience, during the conference, the lights would then be varied for the different stages of the conference, the assistant would activate the desire scene at the push of a button to match the event. Once the conference has ended, a single button press near the exits would be pressed to turn off all the lights and air conditioning.
- After office hours
A button at the entry area is pressed to turn off most of the lights and also the air conditioning.
- Last person to leave
The “all off” button is pressed to turn off all the lights and the air conditioning.
- Holiday overtime
Press a button on the IS45 to turn on the lights in the desired section. The last person to leave presses the “all off” button to turn off all the lights.
There are a lot of customers, when they see the label “smart” will immediately associate it with “extravagant and expensive”, or “it is only for showing off and is not practical”, “computer automation”.
These types of thinking, is based on a misunderstanding the true meaning of smart lighting control.
We believe that the purpose of having a smart lighting control system is the following:
- Increase the quality of life, and yet operation is simplified.
- Simple to operate and practical to use.
- To fulfill the need to save energy especially for public buildings, commercial spaces and factories.
- User control interface can be done through local controls as well as non-local control.
- The components can be adjusted according to a given budget: since different spaces will have differing requirements and the budget for each budget will also vary, then the choice of user control interface can match the requirement and budget, from simple classic wall switches, digital switches, touch panels, to mobile devices. But regardless of the user control interface used, the backend controller devices and communication backbone remains the same.
From the perspective of DAE, a smart lighting control system is indispensable for any wide open spaces, and is quite different from the simplistic traditional one-to-one approach to control. Through the use of a digital bus, control becomes flexible, convenient and simple. It is not the crude approach taken for implementing a centralized control by aggregating all the wall switches into one location, or by using a dedicated computer; either of these approaches are not true smart lighting control.
All newly constructed buildings should consider adopting a smart lighting control system at the very start to maximize its benefit and minimize costs, as later retrofits are costly, time consuming and disruptive. A lot of new projects can chose not to use any central computer as host nor a touch panel as they are not essential for a more modest project.
This new approach of using a digital bus in conjunction with digital or classic switches can achieve effects that cannot wherefore be achieved using the traditional approach, such as the following:
- Multiple access control: The same lights can be controlled from different locations and it is not required that the locations are in close proximity to each other nor to the light itself. It is essential for public spaces such as factory floors, open offices, hallways, libraries, conference halls and other places with large open areas.
- Scene Recall: In order to create the desired mood or atmosphere for a certain room, multiple lighting circuits need to be used. With the traditional approach of having one lighting circuit to one switch, it becomes cumbersome to operate and get right combination of switches to get the right scene. On the other hand, with a smart lighting control system, a single touch of a button actives the entire scene with no fuss.
- Task Selection: Each activity can be assigned to its own control button, such as when leaving home, good night, office hours, after offices. A single button press activates the lighting pattern appropriate for any given task.
- Centralized Control: Having a means to aggregate the controls into a single location is especially advantageous for any public space covering vast areas. There are various options for centralizing control such as with a wall of digital switches, touch panel or having a computer host. Any of which will allow the operator to monitor and control the lights for all areas.
- Automated Controls: Can be achieved through the use of a timer schedule and sensors, both of which enables the lights to work without the need for user intervention.
A smart lighting control system is not just a centralized control system. More importantly, it is a way to replace the traditional form of lighting control with one that is more flexible and capable of doing those things which would be impractical or impossible to do before. Even with all the capabilities of DAE’s lighting control system, it is ultimately designed to make it simple, easy and convenient to use even for the novice. It doesn’t need any complicated software or specialized device to set up. It is also designed to be designed to be simple to install and maintain.
- Multiple Access
Similar to the traditional three way switch, which is having one light controlled from two locations. The same effect can be achieved through smart lighting control through its digital bus.
- Smart lighting control is not limited to just 2 locations, it can have as many locations as desired controlling the same lighting circuit.
- Distance is not a limitation, it doesn’t matter if the switch is on the same floor as the light or on a floor above or below; if control access is not limited to a physical switch, then control can be achieved from outside the building or even be mobile.
- Unlike a traditional three-way switch, the switch needs to be located within line-of-sight of the lights or else the user won’t be able to see if the lights have been turned on or not. With a digital switch, the status of the lights is shown on the digital switch itself, this is something that is not possible with a classic mechanical switch. In addition, with the traditional approach, if additional multi-way switches are needed, the wiring becomes even more complicated.
- Traditional multi-way switching depends on the power being wired connected to all the switches. Such an approach is not practical as power cabling is expensive, and is not flexible as rewiring requires major renovation and is complicated and disruptive.
- Group Control
Group control allows different lighting circuits to turn on or off at the same time as if they were a single lighting circuit.
For example: All the public hallways on the same floor can have their lights be turned on or off all at the same time. The lighting for each hallway is on a separate circuit, in a traditional lighting control this is not possible. But in a smart lighting control system, the different circuits can all be assigned to the same group number, and thus, a single button can command all the lights in the same group to turn on or off at the same time.
- Pattern Control
In the same space, one can exhibit the different combination of lighting effects; that is to say that a single button will activate a pattern consisting of a combination of some lights that are on and some lights that are off, for the purpose of creating a desired atmosphere, mood or to match an event. This in effect is biased towards the artistic side of lighting.
- Sensor based energy saving control
The most commonly seen is the infrared based motion sensor to control the lights. Other less common ones include the daylight sensor, temperature sensor, carbon monoxide sensor and so on.
- Dimming Control
Dimming is most commonly used with pattern control, and often it is accompanied by some form of fading effect.
But it can also be be combined with some simple rocker switch for control, but with only a slight change in having some gradual fading effect. Other than this, there is still the need for some knob to control the dimming level. Our system can also support a variable resistor based form of dimming adjustment.
- Scheduled Timer Control
This is often used in conjunction with group or pattern control. This form of control can cover any of the load controller units on the digital bus. There are multiple tracks to the schedule, one for weekdays, and the other for weekends, then there is also the special days (exceptions and holidays). Modifying the schedule is simple enough that it can be done easily by the administrator to make impromptu changes to accommodate unforeseen events such as a special occasion or a typhoon day.
- Peak and Off-Peak Control
The same lighting can be controlled different for different times of the day. For example, during business hours, the lights would automatically turned on from a schedule, but in the evening when everyone has left, control reverts to the local sensors.
- Centralized Control
For large buildings often a control center is established to be able to oversee the lighting for the entire building. The host computer would have a layout diagram for each floor showing the public lighting. The building administrator would then be able to monitor and control everything from one central location instead of having to roam the entire building just to manage the lights.
The most visible public areas are the hallways, elevator lobbies, restrooms, outdoor lighting and the parking areas. In these places, if their lights are not managed then the only alternative is to leave them on all the time, this works against the effort to save on energy. In reality of course, these places can have different periods of activity, there is a period of high activity with lots of people and traffic, and also a period of low activity with few to no people about. If the lights are unmanaged, then there is no quality of service that is in effect. This article seeks to suggest some ways in which a quality of service can be put into place that is both reasonable and effective, which also helps to save energy at the same time.
With the addition of a lighting control system, the following points can be achieved:
- The time in public areas would be divided as peak, off-peak and no service periods.
- During peak periods, in order to get the best quality service, the lights should remain at their optimal operating condition, at this time, the local wall switches would not be allowed to operate. As such, there is no need to worry that the lights would be inadvertently turned off and thus affecting the qualify of service.
- During off-peak periods, saving energy is the most important consideration, at this time, there are few people about, and the lights can all be turned off or only some turned off, with the ability for local control, this way some form of energy saving can be attained. With some lights being turned off, only a minimal amount of lighting is retained to maintain some form of illumination. Local control is attained using wall switches or sensors that will automatically turn on the lights in the given space.
- During periods of no service, as when offices and business are closed, all the public lighting are off except for the signage and basic lights.
- The lighting can be varied depending on the time and place. The changes should be easy and safe to do.
- Offices and commercial spaces can be divided into different time segments based on activity. Work days and holidays, peak and off-peak periods all have differing levels of activity. Even in any given building, different rooms or spaces with different purposes would have different time segments as well. At different times, different lights would need to be lit or dimmed, all of which can be achieved automatically with a scheduled timer control. Such a schedule should be easy to modify to accommodate temporary and extemporaneous changes, ideally it should be possible to do online and through a web interface. The administrator then won’t even need to go to the equipment room, thus the entire process is not only convenient but also safe.
- During a fire alarm, the lighting mode should automatically change to emergency lighting.
- During an emergency, such as when a fire alarm occurs, then the lights should become emergency lights and all turn on, regardless of what time or mode it was previously operating at, this way they can be put into its best possible use.
- The need for centralization: convenience
- From the point of view of the building management or safety considerations, it should be possible to oversee the lighting for all areas of the building and be able to make changes remotely depending on the situation. This can be achieved by using a bunch of aggregated IS45 digital switches or by using a touch panel.
- With multiple circuit control, there is no need for the lights to remain on all day long.
- In reality, in any given space, there are many lighting circuits and rarely is there only one circuit for all the lights. This is because other than the basic lighting, there are also the non-essential lighting used for decorative purposes only to provide the atmosphere. During off-peak periods, the basic lighting can be turned off to save on energy.
- The local wall switches behave differently during different time periods.
- During peak periods, the lights would be forced to remain on from the control center, and de-authorize the local wall switches from operating. But during off-peak periods or for certain types of rooms, the local user should be allowed to freely operate the wall switches. Classic wall switches are most often chosen for use as the local switch, since they are durable and reliable; at the same time, the user is already familiar with them and their use is intuitive.
- Classic switches can be classified by their use into one of three types:
- Toggle type: Pressing them changes them from one position to another and vice versa. Such as a private office, the user can freely control the lights.
- Push button type: Press once to turn on the lights, the lights will then turn off automatically after a certain delay.
- Multiple access switch: Such as those used in a long hallway or a large hall; it is recommended that push button switches be used, they are connected together using two wires, which will allow control of the lights from multiple locations; i.e. turn the lights on from one spot, and conveniently turn the lights off from a different spot.
- Areas adjacent to natural light, during the day, the lights in these areas would automatically be turned off during the day.
- Outdoor areas such as parking lots, park lights, building wall flood lights and billboards; at different times of the day, different lights would be turned off. The turn on times would vary with the seasons.