Residental Emergency Lighting

Oh and i find it very funny that in Ontario as a junior Electrical Eng. I will start out approximatly 45K salary but as an electrician, I pull in 100K+ without overtime.

Thats okay. I also find it "something" that an electrician can make $100K a year without over time with apparently little basic understanding of electricity and how it works in practical application.

You want to run LED lights for 30 -90 minutes without an external connection to any power source to keep the battery charged or the wireless receiver system powered up.

I would like to run LED lighting within a light for approximatly 30-90 minutes off a battery.

I am looking at a transmitter to be placed on the line side of the switch or a stronger transmitter at the electrical panel which will keep the LEDs from turning on. Once the power goes out, the battery (fully charged) will begin to conduct and illimuniate the LED board. When city power is restored, the transmitter will once again begin to transmit a simple and unique pulse modulated signal which will cause a Open in the emergency lighting circuit , causing the LED lights to turn off and the battery will again be charged everytime the lights are on.

Does this make sense? I wonder if my logic flawed?

Did i say something that caused you to believe that I have little basic understanding of electricity and how it works in practical applications?

The easiest way is to use a 3 wire system (Switched Phase, Constant Phase, Neutral) where 'Switched Phase' is the normally switched phase from the light switch (controlling the light), and 'Constant Phase' is a separate wire that is connected directly to the phase circuit to monitor for the presence of voltage (hence control and recharge the emergency lightning in the event of a power failure).

As you have mentioned, yes you can do this electronically by replacing the hard wired 'Constant Phase' wire with a small radio transmitter and receiver (ie- a wireless version of the 'constant Phase' wire). This is more expensive than the three wire control system but has the advantage of being able to retrofit emergency lighting into an existing home without having to rewire the light. As for the logic, the transmitter just transmits an off signal to the receiver in the emergency light fitting, loss of supply causes the transmitter to stop and the emergency light comes on.

There is probably a simple product on the market (wireless switch) that you could use for this purpose, such as in the following link for example.

http://www.x10.com/automation/index.html#wireless_remotes

Also try a Google search of "wireless home automation"

The concept is intriguing and seems sound. I think it will boil down to economies of scale, with simple radio receiver/relays to control the LEDs. I guess the radio part would be similar to garage door openers, with a similar distance range. They might not even need coding, because any nearby systems would be doing the same thing also; but they would benefit from an assigned frequency so that other types of devices wouldn't trigger them.

I would guess that the installed cost would need to get down to about US$10-20 per unit to make this sell well. One of the challenges will be to come up with a format that adapts easily to all sorts of light fixtures.

Thanks guys for the wonderful information and input. My business goal on this if it has one is to eventually be able with a new home undercontruction.... or to retrofit and changing all the lights........

Thanks guys

One way to do this would involve using a resistor across the switch contact to provide small leakage current (present even when the switch is off).

Power off & signal current > 0 means switched off.

Power off & signal current = 0 means power failure.

Naturally you'd need to comply with all relevant local elec & safety standards.

I am not an electrician but I did use Statscan to try to give my employees fair pay based on others in the industry. I am retired and have sold my business so don't apply for a job. For your information, Statscan 2010 reports average wages (Toronto) for a journeyman electrician as $54,000 per year but that 10% will earn about $75,000 per year and another 10% will earn only $30,000 per year.

An average wage for a supervising P.Eng is reported at $74,000 per year. Supervising I assume means several years of experience. My son is a supervising (46 technicians and technologists) computer software engineer but he will not disclose his salary. Your entry level as an engineer sounds about right but you really are overestimating an employee electrician. If the going rate for electrical contractors is $60.00/ hour, a self employed and very busy contractor could earn over $100,000/year but all his expenses would have to come out (tools Van, other employee, compensation insurance, travel, etc) . FYI

You don't really need to connect your transmitter to the line side of the switch; any local socket outlet will suffice. Plug the transmitter into the socket (turned on of course). The transmitter might be powerful enough to cover the house (local radio regs permitting).

However I have deep distrust of all things wireless. I have 2 options;

(a) monitor the switch line for induced mains frequency signals; it basically operates as an antenna and if power is flowing in the home it should pick up some signal. Of course if not the power is dead.

(b) measure the voltage between neutral & earth. Earth does not normally carry current but neutral does. The difference is due to current flowing (anywhere in the house). Of course this will drop to zero if the power is off.

Do both the above to reduce errors in operation. The electronics are simple. Then no radio waves required.