Uncategorized

Finder’s lighting control components for energy savings

 From a company formed to exploit its founder’s patent for a lighting control relay, Finder SpA has since grown to be a renowned name for such products and today offers reliable, rugged, superior electrical life, high inrush current handling capacity for lamp loads  and high temperature withstand capability to control over lighting circuits and in doing so, save energy.
Special time switches: In addition to a wide range of 24-hour, daily or weekly programmable time switches, Finder offers more specialised versions. Special light dependent relays: LDRs (light dependent relays) will, as the name suggests, switch according to the ambient light levels irrespective of the time of day or when the sun officially rises or sets. Fundamentally a simple device, there are a few refined version available where the light sensing element may be integral with the relay itself, or it is remote. The latter allows the light sensing to be more closely linked to the light entering an open area or a warehouse roof- light for example, or allows it to be less affected by the internal artificial light. This is important to avoid any “hunting” effect of the LDR due to artificial light feedback. An alternative way of achieving a decoupling of the sensor from the artificial light is to use special versions where the LDR’s micro-processor measures and then calculates for the effect of the artificial light and makes automatic correction for this (Finder 11.41 and 11.91 – Series).
“Zero hysteresis” version (Finder 11.41) incorporates special measures to overcome the natural instability that would normally result when having the ‘on’ and ‘off’ switching thresholds at the same level. All these fine tuning measures allow the threshold at which the lighting switches on and off to be more finely set, again contributing to optimising energy saving.
LDRs with time overrideApplications like this can be implemented on a simple case by case basis, and they are probably better served by using a simple stand-alone control component rather than trying to integrate within a wider system or network.
New application-specific movement detectorsBased on new innovative electronics and optics Finder has added three new application-specific movement detectors to its 18 Series range.
Specifically for sensing within larger rectangular areas such as hotel lobbies and long corridors, the 18.41 surveys an area up to 15 metres either side of the device, giving an extensive total detecting zone of 30 metres long by 4 metres wide, from just a single unit. Central to the 18.51 is an advanced lens and electronics system that achieves two detecting zones with different sensitivities. The central 4 x 4 metre zone responds to very small movements, able for example to pick-up on the presence of a person quietly working at his workplace. But additionally, within an extended 8 x 8 metre zone, it will also respond to normal movements. This product is particularly targeted at offices, control rooms, warehouses and the workplace in general.
“Twin-Mirror” technology gives the 18.61 its exceptionally wide viewing angle of 180-degree. Specifically designed for fitting into new or existing wall boxes, the 18.61 can be installed in corridors along with the 18.41 but is equally suited to small spaces such as bathrooms or passage areas. Essentially it can be installed as a direct replacement for a wall mounted light switch board.
All three models share the common characteristics of a wide 110 to 230 V AC power supply range, a 10A rated ‘no’ output contact, adjustable ambient light intervention threshold and a light-off delay adjustable from 12 to 35 minutes.
Depending on the type, these new products can be installed on the ceiling, in suspended ceilings or in recessed or flush mounting boxes.n________________________________________________________Whilst there are some applications where the use of electricity is fundamentally a function of the time of day and the particular day(s) of the week (such as water heating), the control of other applications – such as external lights – may be more relevantly determined by switching times that vary throughout the year and day-by-day. For these cases it may be better to use an Astro time switch (Finder’s 12.81), where the switching times are linked, not to fixed time of day, but to the sunrise and sunset times experienced at the place of installation. This will be dependent on the seasonal time of year and the longitude and latitude – set by entering the geographical coordinates. Whilst the switching action of the control is primarily determined by the sunrise and sunset times, there is also the useful facility to advance or retard the switching about these astro times by as much as 90 minutes (in 10 minute intervals).___________________________________________________Sometimes the need exists for lighting to be controlled according to the ambient light level as well as an overriding time requirement. Although one could of course use a LDR and Time switch in combination, Finder’s 11.91 is a dual-function device, where it is possible to provide an output when the light level requires it, but subject to certain time considerations.  As an example, a shop window display lighting may be required only when the ambient light level is below the set value but overridden to shut off when it is past midnight – when potential window shoppers are expected to be off the street.
But it might also be required that the shop sign, or perhaps low level security lighting, remains on for the full time of darkness. In this instance a second output contact is available which is purely dependent on the ambient light level.

Click to comment

You must be logged in to post a comment Login

Leave a Reply

Most Popular

To Top