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Might be XP-E or XP-C. Can't tell for sure from that picture.

Wondering if anyone can identify these LED's I'm thinking there Cree but not sure.

I would rather not spend any more money on a pwm dimmer if possible.

put my meter across the pot and it read from 0-200vac across the range.  think I might have to stay with the LED/LDR

when I pwm the led over the 0 -100% range, I can only get about a 60% range on the LDR, by changing the resistor on the led it changes the range from 0-60 through to 40-100% can you think of a way to over come this?  Thanks heaps

BTW the incubator is for chicken eggs if any one was wondering.

maybe look for a mains incandescent dimmer that accepts either a PWM or 0-10v control signal... they're usually sold for commercial lighting setups, where you have a big room of lights controlled with a touch pad.

or dig a little deeper into the dimmer you were modifying ... if it's using a POT to control the dim, most likely it's reading some sort of DC control voltage, which you could replicate with your PIC (PWM into a RC network to convert digital to analog)

Hi

I'm making an incubator for my sister,  and being an incubator it must be held within 1 degree of 38degrees less the better. the idea for the circuit will slowly adjust the duty cycle of the PWM to keep a constant temperature. and I have some questions about different ways of going about it.

Firstly here are some details:

PICAXE 18x for the main brain which has 1 PWM output at a minimum of 4kHz
2 x 60W 230v light bulbs as the heat source

First try I opened a mains light dimmer and replaced the dimming pot with an LDR which had an led coupled to it and taped up, and yes it did work, but it was anything but predictable, like it might be 80% and an our later at 10%.

Second try I didn't think it through properly and tried using a zero crossing SSR with a max switching speed of 50Hz and at 4kHz well you can guess!

I have no idea if this has any merit or is even possible, but to rectify 230ac to get about 330Vdc then connect the lamps in series and switching it with a mosfet??? would I be able to just use a rectifier or would I have to smooth it somewhat for the mosfet?

and another thought which I haven't really thought much about yet is to use a /100 on the output PWM to make it 40Hz, but that would stuff everything up wouldn't it? or would it?

any help for pointing me it the right direction would be very appreciated!
Thanks 

I guess I'll have to stick with 12v input LED bulb to make it more practical.
There were 30w 1800lm with 1.5ma
I can probaby use 4 of those...

4000 lm typical with 100 watts power input? 40lm/watt is awful!  But 40lm per $1 is pretty good. Alternately you could purchase 26x 160lm rebels at a cost of about $125, add a 48v power supply and two simple linear drivers , run two series strings (44v each) with a draw of roughly 1.4a off the psu.

Driving the 100w beast using a 12VDC to 120VAC "inverter" you have more options:
(list order: easiest and most expensive to hardest and least expensive)
Easiest way to drive it would be to buy their AC driver and call it done!
Less easy, buy a 36V 4a power supply, a few 100+ watt halogen light bulbs (as series resistors) and you're done.
Less easy still, build your own "offline" switcher, Supertex HV9910.

To generate 100w at 36v you'll need to take in roughly eight to ten amps at 12-14v - that's a pretty beefy boost converter!

This is the bad boy I want to mount on the car..

http://www.lck-led.com/p478/Extreme-Bright-100W-High-Power-Led---White,-30-36v,-3.2A,-6000lm/product_info.html
Is this even possible?? I'm trying to use this as flood lights..

HV9910(b?) might be up to the challenge... possibly other switching controllers that use an external switch.  You might have to get creative in sensing the led current however, or aim for a constant voltage?

Is there way to power the 100W High Power Led (30-36v input, 3.2A) from 12v car power??