Photocell motor

[htmlfreak]

Recently the motor that I used in conjunction with the photocell broke...it was a cooling fan from a laptop. Can the photocell only activate really small motors? (as in require a very small amount of voltage). What other motors have you used in the photocell step?

[Xenarian]

I'll get back to you on this one, but I'm experimenting with photoresistors today, in conjunction with motors.

I really hate how in the rules they said "photocell", as opposed to "photoresistor". Upon reading it, I immediately thought they meant "photovoltaic cell", as in "solar panel". Then I read later in a rules clarification that they really meant photoresistor. How annoying, I spent two weeks trying to make a photovoltaic cell work.

Anybody else have any ideas?

[they might be boned]

We have been having difficulty getting our photocell to even power the motor. If anyone has any advice, it would be much appreciated.

[pjsetnicker]

Hi Guys

Take a look here:
http://soinc.org/official_rules_clarif_2009

Basically: there was a rules clarification that basically states the light has to activate a switch (using a solar cells) that powers the motor. Meaning batteries can be used and this process becomes a lot easier than trying to power the motor with the light itself....

Hope this helps. If you check the Science Olympiad Wiki page you'll see that there's a picture of the circuit you'll more than likely want to use.

[Xenarian]

Sounds good...
Must you use a photovoltaic cell (as in solar cell), though?
Would it be legal to use a photoresistor instead?

I was thinking that one could use the photovoltaic cell to power a relay, and close another circuit. Legal?

[Sir_L_Jenkins]

Actually, you must use a photoresistor, turns out a while back they pulled a 180 and decided that photovoltaic cells such as solar cells are illegal =P

[cypressfalls Robert]

if you connect photocells to a relay you can power bigger motors as well

[Balsa Man]

Everything in this thread has been covered in depth on the Photocell Bonus thread.....-
-what is and is not considered as a "photocell
-use of relays
-how to hook it all up and make it work.

Using a relay allows you to use pretty much whatever motor you want to. We're using a 12v computer cooling fan- (triggered by the photocell unit - )12v/20w bulb, photoresistor, 9v blue Radioshack relay) All powered by a 9.6v cordless drill battery. Works like a charm......
Box ran at 60.04 sec at Regionals yesterday.....

[htmlfreak]

Everything in this thread has been covered in depth on the Photocell Bonus thread.....-
-what is and is not considered as a "photocell
-use of relays
-how to hook it all up and make it work.

Using a relay allows you to use pretty much whatever motor you want to. We're using a 12v computer cooling fan- (triggered by the photocell unit - )12v/20w bulb, photoresistor, 9v blue Radioshack relay) All powered by a 9.6v cordless drill battery. Works like a charm......
Box ran at 60.04 sec at Regionals yesterday.....

Wow 60.04 sec? that's incredible. did you medal?

[Balsa Man]

did you medal?

Oh, yeah; 1st. The other box (our Team 1) was 4th with the touch. We'd have been 1st and second. Both boxes were running within a couple tenths over 60 on Friday night....