Category Archives: Energy Saving Switches

Introduction to Lighting Energy Saving Switches

A good design should take the characteristics of the space into consideration, such as how often that space is occupied in order to determine the approach, which could be one of the following:

  1. Occupancy Mode
  2. Vacancy Mode
  3. Simple manual control using a wall switch
  4. Manual switching with delayed auto off

K15 Occupancy

The basic premise is to have people manually turn the lights on. Often used for places which are not occupied for very long, where people come and go but not very frequently. Places that are infrequently used such as restrooms, elevator lobbies late at night, storage rooms, laundry rooms and so on.

Method of Control: Manual on, auto off.

Normally, sensors are used for motion, with infrared types being the most common, but basement parking is quite warm, and restroom is partitioned into stalls both of which diminishes the effectiveness of IR sensors unless the delay time is somewhat prolonged.

Solution: Lights can be turned on from any wall switch or by the use of sensors, after which a delay starts:

  1. Wall switches may still be used to turn the lights off manually, the sensor will enter standby mode after 30 seconds.
  2. If after the 30 second delay is up and there is no motion such as a hand being waved over the sensor then it means that no one is around, then the lights are turned off and the sensor enters standby mode.

In the past, sensors are quite commonly used, but having the sensor turn the lights on and off too frequently will only harm both the lamps and the relays controlling them, by shortening their lifespans. But there are times where the lights does not need to be turned only, but the sensors turn them on anyway which results in unnecessary wastage of energy. If this were to affect an infrequently used small room with only a few lamps, then it wouldn’t matter much, but if it were for a large area such as an elevator lobby, hallway or a restroom, then the lifespan of the lamps would be substantially be reduced. In addition, large capacity lamps such as gas discharge lamps, streetlights, where a long start up time is needed, then sensors are also inappropriate.

Application Features
  1. Upon leaving, the occupant may manually turn the lights off; no need to wait for the delayed auto off to kick in.
  2. At night, from the bedroom to the bathroom, the lights will turn on automatically, but the lights can be turned off at the bedside manually (K15 with the push button switch)
  3. A long press on the push button connected to the K15 can have the lights remain on and temporarily ignore the sensor.

Vacancy Mode

Application Area: Public spaces that are occupied for prolonged periods such as reception rooms, offices, workshops, classrooms, libraries and labs.

This is a supplementary capability to help turn the lights off to avoid wasting energy for public spaces when they are not occupied.

Method of Control:
  1. Lights can only be turned on manually
  2. When the occupant leaves they can turn the lights off manually; but if they forget then the auto off kicks in.
  3. If the delay off time is almost up, one needs only to wave at the sensor to extend the delay.
  4. The lights can still be forcibly turned off in instances such as when doing a presentation or when taking a nap.
  1. The lights need to be turned on manually from the switch.
  2. When the occupant leaves, they should turn the lights off manually, but if they forget, the controller will turn the lights off automatically. The purpose of vacancy mode is for when the occupant leaves and the room becomes vacant.
Application Features
  1. If someone is just passing through and has no actual intention to turn the lights on, then it won’t turn on.
  2. If the lights need to be turned off then it can be, such as when making a presentation or taking a nap.

K20 Delay Switch

Area of Use: Hallway or stairwells; their primary use is for controlling the lights in long passageways or corridors. Push button switches should be installed along the length of the passageway for the convenient operation by the occupant.

Equipment: Multiple push button wall switches are installed along the length of the passage and connected in parallel, this would allow the lights to be turned on from anywhere and turned off from anywhere; anywhere a switch is installed. If the user forgets, the lights will still turn off automatically.

Energy Management for Administrators

In any school, office building or commercial center. Once the construction of the building is finished and turned over to the building management, problems with energy management begin to surface. What techniques can be applied to rectify this situation.

  1. Different types of spaces should make use of different techniques:
    1. User pays:
      Can be applied to classrooms, dormitories, piano rooms, and any other rental places where the user has the responsibility for using the space.
    2. Conditional use:
      Can be applied to open offices, meeting rooms, libraries and similar shared spaces where no tariff can be charged to any particular user. These spaces can make use of energy saving controllers that allow operation depending on conditions, such as the time of day, having temperature thresholds, or making use of sensors.
    3. Scheduled or sensor control
      Public areas such as hallways, elevator lobbies, halls, outdoors and parking lots could either be controlled through a schedule or by using sensors.
  2. A control center is not all knowing, and having local control would be more effective
    Some time ago, when an energy management issue arises, the knee jerk solution is to implement some form of centralized control, but such an approach is not only expensive, but it also doesn’t really solve the problem.

    1. Local automatic control
      For certain spaces, there are ways in which there would be conditions that would allow for local automatic control without having to rely on centralized control, central control would merely serve as a supporting role.
    2. What are some of the methods of conditional control?
      1. Insert card to use:
        Such as with a teacher’s card or a card borrowed from the administrator, only with this card inserted would use be allowed.
      2. Controlled time of use and temperature thresholds, this is especially suited to air conditioners.
      3. Preset time power reset
        This would prevent not turning off after use. Every day there would be specific times of the day where the power would be reset, this is accomplished by first cutting the power off, then after a short delay, the power is restored, but the equipment would remain off, the equipment could only be turned back on manually by the user.
  3. Automatic energy saving methods
    1. Delayed auto off: After the user turns the lights on, the lights would automatically turn off after a certain delay.
    2. Sensor based auto off: When the user enters a room, they need to manually turn on the lights, the sensor monitors the presence of the user, when the user leaves, they can turn the lights off, but if they forget after leaving, the sensor detects their absence and automatically turns the lights off after a certain delay.
    3. Scheduled on and off.
    4. Reduced consumption control: alternate lamps, dimmed lights, temperature restrictions.
    5. Sensor control: Such as temperature, lux sensor both indoors and outdoors, occupancy sensor.

Energy Saving Control for Outdoor Lighting

Energy saving control for street lighting, parking lots, daylit hallways and building facade lights.

Public outdoor lights are on for long periods of time, they cover large areas and are very bright, and thus they often enormous amounts of power. But since they are in the public, they are very visible and noticeable, oftentimes they are already on even when there’s still light, which gives the public the impression that there is no effort to save on energy, and management is ineffective. Hence, this is a focal point for energy management.

Most traditional approaches to energy saving for outdoor lighting is by making use of automatic control to turn the lights on or off, which works in conjunction with light and dark to automatically turn the lights either on or off, but this approach has several shortcomings.

  1. The lights should come on when it becomes dark, but it doesn’t mean that the lights should remain on up until it is light before turning off. The best approach is to have a different time schedule for each light post depending on its location to turn the lights on at a designated time and to turn it off early. But if automatic control is dependent entirely on a daylight sensor, then the lights would only turn off when it is light. The correct approach would be to turn on at a certain time depending on the venue, and turn off at a designated time, it should not be that the  lights only turn off when it is light. This is not something that can be easily done using a simple daylight sensor. But if a timer is used, it cannot adjust its time to match seasonal changes, and can either turn the lights on too early or too late.
  2. It can often be seen in sidewalks, that even though it is already daylight, the street lights are still on, this is often caused by the daylight sensors when their calibration skews over time. Or it could also be caused by having its receptors obscured by trees, nearby buildings or plant overgrowths, which causes it to malfunction. This results in much wasted energy and also in reducing the lamp lifespan, constantly maintaining the street lights to ensure that they are operating in peak condition is labor intensive and costly for both its labor and materials.
  3. The sensitivity of daylight sensors can vary widely, which can be seen in some areas wherein a segment of lights being turned on, while another segment in the same vicinity remaining off. This appears inconsistent and gives a bad impression to the public and reduces the quality of service.
  4. Daylight sensors do not gauge dimness in the same manner as people do, which causes the daylight sensors to turn on the lights even though people still think it is still light. This of course results in unnecessarily wasted energy. The administrator is unable to make adjustments to and is entirely at the mercy of the daylight sensor in deciding when to turn on the lights.
  5. The location in which to install the daylight sensor is very finicky, if there are objects or structures close by that could potentially block its receptors, then it could cause it to make faulty decisions. If the daylight sensor is in an ideal location, it could be far from the switch that controls the lights, which means that additional wiring need to be laid out from the sensor to the switch, which of course means additional labor and material costs, not to mention the difficulty in the actual construction job.

Improved Approach

  1. Make use of the K40 monthly adjustable controller, each month would have its own turn on time, which solves the problem of indeterminate turn on time, and won’t turn on too early nor too late. Since there is no longer the need to install a daylight sensor, it also eliminates the problems associated with the laying of the conduit wiring. Thus, costs are reduced. Turn on times are not determinate and all lights could now be synchronized.
  2. Depending on the place and purpose, it is not always necessary to have the lights all turn off at the same time, as for example, the circuit could be arrange so that the light posts alternate, or grouping could be made into primary and secondary circuits, and each group could have their own turn off time. Applications for this such as for billboards, exterior building wall wash lighting, pathways, streetlights, parking lots.
  3. Late at night, when few people are about, such as in parking lots, one could make use of the LT3000 with motion sensors, so that instead of leaving the lights on all night, they will only turn on when there are people about. Which also helps to reduce wasted energy.

In Conclusion

Daylight sensors are simple in principle, and they are inexpensive. But the difficulties that they cause results in much energy wasted and also in reduced lamp lifespan. With the use of the K40 and the K90 in combination with push button wall switches can be used to adapt to the routine and also helps to reduce energy use at the same time. In addition, they can be adjusted to the venue and seasonal changes, with the ability to change the turn on and turn off times which allows the administrator to be in control at all times.

Energy Saving Control for School Computer Rooms

Some schools have computer rooms that are open for the students to use, after peak hours most of the students have left, and so most of the time the room is unoccupied, but the lights and air conditioning all remain on, which results in much energy wasted.

Computers rooms are divided into multiple sections and each section would have their own lighting and air conditioning energy saving switch.

  1. The student can manually operate the buttons to turn on the lighting and power outlets in a given section.
  2. The air conditioning would be restricted: only when a certain temperature threshold is reached would the air conditioning be allowed from being turned on.
  3. Once the students have left, there will be a period of time where the room is being observed by the sensor to make sure that everyone has truly left, then it will automatically turn off the lights and the air conditioning.

Energy Saving Control for Small Rooms

Most small rooms such as pantries, copy rooms, smoking rooms, restrooms have people coming and going frequently but staying only for a very short time; they only a single circuit and the K15 or K24 smart sensor switches would be suitable for delayed auto off control.

  1. The K15 or K24 is recommended for such applications.
  2. Operate using the occupancy mode; lights will turn on when people come, lights turn off when people leave.
  3. Since these spaces have small areas, the lighting load is also low; hence, the internal relays of the K15 or K24 can be directly connected to the lighting without reducing the lifespan of the relays.
  4. It is recommended that the delay time be set to about 10 minutes or so.
  5. The sensor should not be installed near windows or ventilation openings as to reduce the false triggering.

How Does the K15 Differ From an Ordinary Motion Sensor?

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
  1. Turn the lights off manually before the auto delay off kicks in.
  2. Augment the blind spot of the sensor, enabling the lights to still be turned on manually when needed.
  3. 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).
  4. 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.

  1. The lights need to be turned on manually.
  2. 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.
  3. 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
  1. 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.
  2. 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.
  3. Since the push button is low voltage, then there is little danger of electric shock from leakage currents.
  4. 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.

9 Energy Saving Principles

  1. Event venues open to the public
    Large public multi-purpose venues such as conference halls and gymnasiums have staff use control switches that are restricted to the public. The staff often needs to roam large areas just to control them which is inconvenient and time wasting. Thus these places are ideal candidates for being remotely monitored and controlled.
  2. Schedule remote control
    The schedule should be easily changed without the need for a specialist. The schedule should have different control methods for peak and off peak periods. During peak periods, local controls are disabled and central control takes over completely. While during off-peak periods, central relinquishes control to the local, and the local control could be achieved using either sensors or wall switches.
  3. Daylight Harvesting
    The purpose of which is to reduce the amount of artificial lighting needed by maximizing the use of natural daylight. This can be achieved by using either a preset time schedule or by using lux sensors during daytime.
  4. Restrict the Use of the A/C
    There should be conditions before the air conditioning can be turned on to avoid having turning them on arbitrarily. These conditions can be in the form of having a temperature limit, time restriction or card insertion before allowing the a/c could be operated.
  5. More Granular Circuit Wiring
    The lights and the air conditioning should be on separate circuits, while each area should divided into smaller areas, this way the lights need not all be turned on and off all at the same time, and only specific areas need to be lit.
    Taking into consideration whether or not the area is exposed to daylight or adjacent to a window is also very important in how the circuit wiring is to be divided.
  6. Single Rooms
    The most power consuming portion of any building are the many individual rooms when added together. Thus they are the focal point of any energy saving measure.
    For rooms that can charge the user for its use, then a prepaid card system or a remote tariff system should be used as much as possible, as these would be the most effective and fair methods to implement energy saving.
    For rooms that are suited to charging the user, then one can make use of a remotely controlled system in conjunction with interactive energy saving smart switches. The purpose of the remote system is to control the room either through a preset time schedule or by the facility manager. The facility manager can decide whether or not to turn on the lights and a/c depending on whether or not there are people present.
  7. Local Conditions
    Rooms with different functions would also make use of different types of energy saving smart switches.
    For discrete rooms or small rooms, one could make use of sensor based energy saving smart switches such as the K24 or the K15. These can be operated in either occupancy or vacancy modes of energy saving control.
    Occupancy mode is used for rooms wherein people go in and out frequently and stay only for a short time such as the restroom or the kitchen.
    Vacancy mode is used for rooms wherein people stay for a long periods of time such as the reception area, lounges and offices.
  8. Air Conditioner Energy Saving Smart Switches (K62)
    In order to avoid having the a/c used unnecessarily, one can utilize the K62. The a/c can only be turned on manually when the temperature conditions are met; when the occupant leaves, the a/c is turned off automatically after a certain delay.
  9. Power Socket Control
    It is not only the lights and the a/c that can be placed under managed control to save energy, but the power sockets can be as well. As a matter of fact, power sockets can be as much a source of saved energy as well and cannot be ignored.