- Class I : Touch-accessible metal components connected to the protective conductor. The protective conductor terminal is indicated by a symbol.
- Class II : Live components are provided with additional protective insulation. Connection to the protective conductor is not allowed.
- Class III : Luminaires operated on safety extra-low voltages (<42V) that pose no danger to human beings.
Wednesday, April 21, 2010
Luminaires - Class of Protection
Luminaires are divided into three classes of protection according to the protective measures taken against electric shock.
Degrees of protection IP
The mechanical design of luminaires must be such that they are adequately protected against the ingress of foreign bodies and moisture. the degree of protection is indicated by the IP numbering system."Ingress Protection"
The first numeral indicates the degree of protection against foreign bodies, the second numeral protection is against water.
An IP 20 luminaires , for example , is protected against the ingress of foreign bodies >12mm (2).but not against moisture (0).
A luminaire designed for use in damp interiors,with a degree of protection of IP 65 is protected against dust (6) and against jets of water (5).
The first numeral indicates the degree of protection against foreign bodies, the second numeral protection is against water.
An IP 20 luminaires , for example , is protected against the ingress of foreign bodies >12mm (2).but not against moisture (0).
A luminaire designed for use in damp interiors,with a degree of protection of IP 65 is protected against dust (6) and against jets of water (5).
Quality features in lighting
Like occupational and recreational activities such as reading a book, assembling miniature electronice components,doing techinial drawings,running colour checks in a printing works etc. visual tasks vary in their requirments.
These visual task determine the demands to be made on the lighting system.
Careful planning and execution are prerequisites for artificial lighting of good good quality .Here is what specific "quality features"determine:-
These visual task determine the demands to be made on the lighting system.
Careful planning and execution are prerequisites for artificial lighting of good good quality .Here is what specific "quality features"determine:-
- the lighting level- the brightness
- glare limitation - undisturbed vision with neither direct nor refleted glare.
- harmonious distribution of brightness- an even balance of luminance.(brightness)
- the light colour - the color appearance of lamps, and in combination with
- colour rendering- the correct recognition and differentiation of colours, and room ambience,
- the direction of light and
- modelling - the recognition of three-dimensional forms and surface textures
- visual performance by adjusting the lighting level and glare limitation,
- visual comfort by colour rendering and harmonious brightness distribution,
- the visual ambiance by selection of light colour, lighting direction and modelling.
Monday, April 19, 2010
lampu hiasan rumah
Lampu menyerikan dan memberi keselesaan kediaman anda terutama waktu malam .
Di samping konsep hiasan dalaman yang lain seperti wall paper,tiling, cat, budget lampu selalunya tidak diambil berat sama sekali oleh tuan rumah?
Mengapa? Kenapa?
Ia merupakan alternatif cahaya matahari di waktu malam, penglihatan yang tidak mencukupi adalah merbahaya - menyebabkan kemalangan dan merosakkan mata kita maka haruslah diberi keutamaan dengan sewajarnya.
Pemilihan jenis lampu yang sesuai aspek di ambil kira :-
- keselamatan - jenis lampu harus mempunyai ciri-ciri keselamatan ( IP rating) - Ingress Protection seperti kalis air bagi lampu kolam,bilik mandi, atau lampu taman ,- juga cara teknik pemilihan lampu seperti sensor light iaitu mengesan kehadiran tetamu tak diundang atau binatang mencerobohi kediaman anda.
- Rekaan yang sesuai dengan konsep untuk rumah anda - modern, klasik,contemporary ,neo-klasik atau balinese konsep.
- Silauan- lampu yang tidak sesuai akan menyebabkan silauan yang ketara justeru pasti menjejaskan penglihatan anda terutama semasa membaca ,memasak dan menjahit .
- Jenis bulb - (lamp and gear) yang di gunakan haruslah tahan lama -jimat tenaga (energy saving lamp). beberapa jenama terkemuka seperti Philips, Osram dan Sylvania disyorkan.
- dimmer - mengubahsuai peratusan keterangan cahaya lampu.
Teknik pencahayaan lampu
- general
- spotlight
- task