How many luminaires

I have managed to get some printable aluminium stickers from RS and am wondering whether it would be acceptable to put these on the BC lampholders as a warning not to use a lamp of more than 50W. Originally posted by: cmatheson I agree, the cpc can be an issue. Originally posted by: cmatheson. Helpful thoughts. Thanks Chris Matheson. But, im pleased to say that over the years, Gu10 fittings have got better and better with regard to connections for all conductors..

Apologies I did confuse cpc with cpd. Mind you I cant seem to see what the relationship is between area and number of cpd's. If anything, more the greater the number of cpd's for a given area, the greater the risk from a faulty device.

For that matter why m2 for a ring main. I'm sure there's some science to it but I'm sure I don't know what science! The m2 comes from research back in the s into space heating using electric heaters, basically you can heat m2 without overloading a 32A circuit. This is also the derivation of the 'unlimited sockets' as once you have plugged in 'enough' heaters nobody would be likely to plug in more. Whilst I am at it - it's also the reason we have 13A plugs, it was going to be 10A until all the Londoners at the planning meetings remembered it gets cold And grim up North and they used 3KW 13A heaters rather than the 2KW ones that were normal in the south.

Clearly all a little redundant nowadays as very few houses are entirely heatied from sockets And I think the 17th edition has been stepping away from the 'limit' which they now describe as 'historic' in appendix With regard to your original point - I think there is a valid argument for a change in the guidance And the diversity calculations as W lamps have been phased out and a point design might be entirely reasonable for a modern house.

Look outside the box; n the event of a short circuit the magnetic portion of the MCB will operate the circuit breaker in In In the event of a continuous overload the thermal portion of the MCB will operate in the times given by the manufacturer 1.

So after a period of the time 2 hours, 1 hour, 30s who knows the overload will increase to 1. If you design your 6A circuit to run on a load of 7A then this is bad design and the likelihood of nuisance tripping is there its takes very little current to throw the MCB over the edge.

So continuous load of 7A is an overload, after 1. I am not saying you are advocating designing a load for 7A and putting it on 6A breaker, what I am doing is questioning your theory behind the statement "The tripping time for a 6A breaker even under a 7A load is NEVER ", when the manufacturer says different. The fusing current is 1. New here? To participate in discussions, please log in and introduce yourself. The pigtail method means you use a 6-inch black spare wire to twist all the black wires together that are connected to the fixtures.

Once you twist the black wires together, onto the split joint, screw a wire cap. Use the same process to connect the ground cables to the ground terminals. As for the white wires, a pigtail is not necessary. The only thing you do is twist them altogether then cap them. The home-run wiring can become cumbersome when more than two lights are connected to a single switch.

You may also need a bigger electrical box to hold all the cables. Now that we have looked at the ways of wiring more than one light to a single switch, you are probably wondering, how many lights can be on one switch depending on the bulbs type of lighting used. Each LED or CFL bulb normally produces the same amount of light as a 60W incandescent bulb while the current it draws is 10 watts or less. Recessed lights provide a room with ambient light that is attractive.

Recessed lights are fixed behind a ceiling, and in order for a room to be well lit, you need more than one fixture. The number of lights that one switch can accommodate depends on a number of factors. These factors include the room shape and dimensions, canister width, and bulb wattage. The number of lights you can add on a circuit is also determined by the breaker rating. Proper spacing of recessed light bulbs results in equal illumination of each part of the floor.

Since each light bulb provides a cone of light, the ideal setting should allow the cones to overlap. For the light cones to overlap, a few factors need to be observed. For example, a room whose height is 8 feet, the standard spacing will be 4 feet.

Improper use of recessed bulbs or overusing them results in the poor quality of the light they produce. The best pattern to place recessed light is an irregular pattern. Avoid spacing the lights too close to each other as you might end up with too much illumination. However, if the fixtures you are using are directional, you may need to space them in closer proximity compared to omnidirectional lights to get a good lighting effect in the room. To determine how many recessed lights a room needs, you first need to define the space.

If you have an open floor plan that combines several living areas, think of each area as a separate room by creating imaginary walls to define them. Then you can measure and calculate each space separately. Notice how the number of lights for each space was calculated separately. Tall ceilings allow the cones of light more distance to spread than low ceilings, so they provide plenty of coverage for the room.

For ceilings taller than feet, using LED lights with a narrow flood beam angle will get more of the light down from the ceiling to the surface plain. Once you know how many lights a room needs, you can use this calculator to create a reflected ceiling plan. Skip to content. Home How Many Recessed Lights? How Many Recessed Lights? Make a payment. Payment could not be made. Pay now. General Lighting Calculator 1.

Room Length Longest Side. Room Width. Select the ceiling height:. Select the ceiling type:. Length lights: 1. Length lights: 2. Length lights: 3. Length lights: 4. Length lights: 5. Length lights: 6. Length lights: 7. Length lights: 8.