Ceiling light electrical supply

LimMurf

Hello to anyone reading this, I'm currently in my final year of Product Design in DIT in the conceptual stage but soon I will have to start creating prototypes.. My question is, what kind of power is usually output by the ceiling light source? The product I'm working on will most likely be run through that source. I need the voltage, amps and any other information I can possibly get to be honest. Thanks in advance!

CountyHurler

The wattage of the bulbs give you the power used...

also Power = Voltage x Current if you need to work the current.

For example,


For a 100 watt lightbulb plugged into a 240v mains

P=VxI
I = 100/240 = 0.42A

adrian92

As County Hurley said the power drawn will depend on what load is connected (e.g 60 Watt, 100 W etc.).

The lower the resistance (bigger wattage) of the item connected to the ceiling light the larger the current drewn (and hence the power drawn from the lighting circuit).

A lighting outlet will have (as a general guideline) an available power in the order of hundreds of watts (as opposed to the kilowatt range). Connecting electrical loads in the kilowatt range is not an option for a lighting circuit.

(Individual light fittings may limit the power connected to prevent the fitting from getting too hot from the heat dissipated from the light bulb)


In summary - the ceiling light power output depends what you connect - but do not connect an item that is going to overload the circuit (hence no more than some hundreds of watts)

ted1

LimMurf wrote: »

Hello to anyone reading this, I'm currently in my final year of Product Design in DIT in the conceptual stage but soon I will have to start creating prototypes.. My question is, what kind of power is usually output by the ceiling light source? The product I'm working on will most likely be run through that source. I need the voltage, amps and any other information I can possibly get to be honest. Thanks in advance!

It's mains AC, usually without an earth. As stated above the power is restricted by cable sizzle and breaker.

Might what ever your using require an RCB which lighting circuits don't have

brightspark

:eek:


You don't know what the normal voltage at a ceiling light is (230VAC) and you are going to make a prototype!

As regards Amps? Are you asking how much current you can draw from a lighting circuit, how much current you can draw from the ceiling rose, or how much current you can draw from the actual lamp holder?
Or is the question how much current is typically drawn by a lamp? What size lamp? A 100w filament type or a 3w LED?

Mains voltage is too dangerous to mess around with, get someone competent (at least a qualified electrical engineer, not another student) to assist you.

Don't rely on the advice given here, it varies from extremely competent to unbelievably dangerous.

Can you reconsider your product? Perhaps something battery powered?

It's understandable that you may not want to disclose details of your product publicly here, but that makes any advice given even less accurate.

BE VERY CAREFUL. badly designed circuits can start fires, such as those reportedly caused by cheap phone chargers, and mains voltages can kill!
Lighting circuits also rarely have earth leakage circuit breakers, so there is a greater chance of a fatal shock current.

aido79

LimMurf wrote: »

Hello to anyone reading this, I'm currently in my final year of Product Design in DIT in the conceptual stage but soon I will have to start creating prototypes.. My question is, what kind of power is usually output by the ceiling light source? The product I'm working on will most likely be run through that source. I need the voltage, amps and any other information I can possibly get to be honest. Thanks in advance!

The voltage will be 230 volts regardless of what is plugged into it. The amps will depend on what current prototype draws from the source. I'm guessing you don't really understand the relationship between voltage(volts), current(amps) and power(watts)?

LimMurf

Hi, thanks for your help with this everyone.. The story is, I was talking to one of my lecturers with regards to my product development and he was telling me to look into the electricity supply from the ceiling. He was saying that he was pretty sure the power supply was very different at a ceiling light source to that of a mains power source. I was looking for information online with regards to this and couldn't find anything so I thought boards would be my best bet! Don't worry, I don't intend on installing any sort of prototype into the ceiling at any stage but I just need to know pretty much every element of the design and how it will work. My lecturer also mentioned that ceiling power sources are very sensitive to any inconsistencies and will easily trip the system, can you guys confirm?

Just to give you a bit of information on the product I am designing, it is a lighting product based around sleep and light cycles and how it effects melatonin production. The purpose of the product is to increase the efficiency of sleep using a combination of light frequency control and olfaction sensory triggers. Olfaction being sense of smell. At the moments, I intend to include an oil atomizer for permeating scents into the air and RGB LED's. Do you think these elements would be safe to use in a ceiling lamp..? Again, I will not be testing this until it is 100% safe, I just need some more informed opinion.

Thanks for all of your time in replying

P.s. Sorry for my lack of knowledge and terminology

braddun

use a big cable to wire it


the more amps the better


don't forget about volt drops

2011

LimMurf wrote: »

He was saying that he was pretty sure the power supply was very different at a ceiling light source to that of a mains power source.

In Ireland the supply at lighting points and socket outlets is 230V at 50Hz, so both are at mains voltage. However the type of protective devices used and the cable sizes differ.

I don't intend on installing any sort of prototype into the ceiling at any stage but I just need to know pretty much every element of the design and how it will work.

We have some very helpful and experienced posters on this forum that I am sure will assist.
However it is worth pointing out that the vast majority of electricians and many of the engineers that post on this forum studied in DIT in Kevin Street.
Seeing as though you are also a student in DIT at present it may be an idea for you to discuss your project with one of the lectures in the electrical department.
A few minutes face to face discussion could be extremely beneficial.

My lecturer also mentioned that ceiling power sources are very sensitive to any inconsistencies and will easily trip the system, can you guys confirm?

With all due respect to your lecturer these sort of remarks are misleading and only lead to confusion. Can you explain what is meant by "inconsistencies".

Just to give you a bit of information on the product I am designing, it is a lighting product based around sleep and light cycles and how it effects melatonin production.

Hence the reason that you would prefer to mount it on the ceiling I assume? Do you want this unit switched on & off by the light switch?

The purpose of the product is to increase the efficiency of sleep using a combination of light frequency control and olfaction sensory triggers.

By frequency control do you mean that you intend to vary the electrical frequency? i.e. the frequency of the voltage flowing through part of your product?

Olfaction being sense of smell. At the moments, I intend to include an oil atomizer for permeating scents into the air and RGB LED's. Do you think these elements would be safe to use in a ceiling lamp..?

This could be done safely, it depends on your design.

Again, I will not be testing this until it is 100% safe, I just need some more informed opinion.

A number of electrical tests should be carried out to determine that the product is safe. These tests should be documented to show due diligence.

When using mains voltage you should consider the dangers of mains voltage electricity.
They fall under two main categories:

1) Shock risk
2) Fire risk

The risks of electrical shock can be significantly mitigated if the product is double insulated. This also means that if the wiring of the installation does not have an earth cable (this often happens) this product can still be installed as double insulted devices do not need an earth. However if this option is impractical / impossible it is not a show stopper, many light fittings are not double insulated.

What sort of electrical load will your product represent (inn terms of watts or amps) ? Is their a heating element within your product? How does the oil atomiser work? Internally what voltage does this device work at?

BTW LEDs use very little power.

Bruthal

With regard to frequency, the op might be referring to the colour of the light.

2011

Bruthal wrote: »

With regard to frequency, the op might be referring to the colour of the light.

Agreed.
There are a lot of gaps in the above, just trying to build a picture hence my clatter of questions

moonlighting

there is a program you can download for free http://www.dial.de/DIAL/en/dialux-international-download.html
its for testing lighting simulations. so say you put in a 100watt bulb of certain manufacture in centre of room this program generates the lux levels and stuff so you can see how well lit up the room would be.

LimMurf

That's exactly what I'm talking about! From 450nm to about 710nm based on the effect on melatonin supression!

LimMurf

Yes control via the main switch is my ultimate goal as I need this product to become the primary light if it is to work properly. Possibly a backup battery to keep the arduino running a small bit of code.. Do you think that would be possible? Arduino runs on 5v

I don't know a lot of the technical specifications as I haven't begun the engineering process, I'm still in the conceptual stage but just trying to get information to better inform my design!

Atomisers don't use heat but use air and pressure to turn the oil into vapour! It would also only run for no more than 7 minutes at a time! Trying to find more information online about the atomiser vaporiser but there isn't much there..

Thanks for all of your help! And everyone else's help too!