Using fluorescent lamps with motion sensors and photo-cells
- Thread starter jeff1166
- Start date
- Status
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
There are some motion sensors and photocells that are designed to work on fans or fluorescent lights. I could not tell you the technical why but there must be something with the ballasts or motors that causes havoc on the sensors.
K8MHZ
Senior Member
- Occupation
- Electrician
I have been using motion / photo sensors with CFL's for years with no problems.
weressl
Esteemed Member
Some of those devices operate a SS power switching device which does not operate well with ballasts or CFL's.
If there is a short duration occupancy, such as bathrooms, the fluorescents will be switched far more frequently than the optimal burning duration of 8 hours and will depreciate their life significantly. So you saving on energy but paying in replacement lamop cost.
Perfect example and application why the incandescent lamps should be kept in service and not outlawed.
hockeyoligist2
Senior Member
- Location
- close to greenville sc
Some of those devices operate a SS power switching device which does not operate well with ballasts or CFL's.
If there is a short duration occupancy, such as bathrooms, the fluorescents will be switched far more frequently than the optimal burning duration of 8 hours and will depreciate their life significantly. So you saving on energy but paying in replacement lamop cost.
Perfect example and application why the incandescent lamps should be kept in service and not outlawed.
I agree weressl!
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
100521-1835 EST
I will distinguish between two broad classes of controlling devices as -- two wire and three wire. Two wire and three wire devices are my definitions and devices of these categories may have more wires than the classification.
A two wire device is connected in series with the load and has no other source of energy to power the device than series leakage current thru the controlling device and the load. Most inexpensive phase shift dimmers fall in this category. Probably all CFLs have as an input a bridge rectifier and filter capacitor. When the lamp is off very little leakage current flows in most of these devices. Thus, not enough energy to power the controlling element. This type of device may have a EGC that does nothing but ground the conductive parts, and might look like a three wire device, but functionally is not.
A three wire device has two wires that are connected to the source hot and neutral wires and thus has a source of power and phase information independent of whether or not a load is connected to the output and the type of load. And a third wire wire that is the controlled output. An actual unit may look like a four or five wire unit. One extra being the EGC, and a second being switched full voltage output.
There are additional problems that determine whether or not a particular controlling device can work with a particular load.
.
I will distinguish between two broad classes of controlling devices as -- two wire and three wire. Two wire and three wire devices are my definitions and devices of these categories may have more wires than the classification.
A two wire device is connected in series with the load and has no other source of energy to power the device than series leakage current thru the controlling device and the load. Most inexpensive phase shift dimmers fall in this category. Probably all CFLs have as an input a bridge rectifier and filter capacitor. When the lamp is off very little leakage current flows in most of these devices. Thus, not enough energy to power the controlling element. This type of device may have a EGC that does nothing but ground the conductive parts, and might look like a three wire device, but functionally is not.
A three wire device has two wires that are connected to the source hot and neutral wires and thus has a source of power and phase information independent of whether or not a load is connected to the output and the type of load. And a third wire wire that is the controlled output. An actual unit may look like a four or five wire unit. One extra being the EGC, and a second being switched full voltage output.
There are additional problems that determine whether or not a particular controlling device can work with a particular load.
.
Bigrig
Member
- Location
- Dayton, OH
That is why programmed start ballasts are available. For situations where occupancy sensors are used to control fluorescent ballasts they will prevent the lamp life loss you are talking about.
mcelweec@gmail.com
CMAC1
- Location
- NYC
- Occupation
- Electrician
also some motion sensors have minimum operating loads.
chevyx92
Senior Member
- Location
- VA BCH, VA
Me too..............
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