Recent content by astroastro

Bicit- I would take a serious read of Bridgelux's application note 'AN30: Effective Thermal Management of Bridgelux Vero LED Arrays' prior to attempting to run 2.2A thru that module. It will get very, very hot at these current levels. Ensure you use the correct type of power supply for...

600d refers to the thickness of the cloth material used to make the tent. A tent made from 300d material is very thin material and will be on the cheapest of the cheap Chinese made tents. A 600d tent is made with a thicker, much more durable material. The 'd' stands for 'denier'- I...

Snaps is right- the arcing is occurring across the switch contacts- not the coils. This occurs when the relay is turned off- there is current flowing in the circuit- when the switch contacts suddenly open (the relay is turned off) the current still wants to flow and will continue to flow...

wth- I feel for you- I had similar problems. Looked thru the specs of all the environmental controllers like the Autopilot and the CAP and the Sentry, but was unable to locate one that was reasonably priced or even do what I needed it to do. Had to design my own. Used thermostatic...

Gonna- not sure if what you have there is going to run at 80% efficiency as you expect. The source current of the FET is going to be carrying all the overhead volatage from the LED strings (supply voltage of 14 or 26V - string Vf x FET source current). You are going to be running this...

I think the black stuff is a not so good attempt at a conformal coat for the PCB- it is supposed to be there for the protection of the PCB. As to what is causing the failure you mention- I have no idea. It would seem as thought the starter is establishing an arc, but there is...

Gonna- with a few extra parts your schematic would technically work, but it is a very inefficient design in terms power efficiency and part utilization. Just an opinion- what you need to do is get a dedicated voltage clamped, constant current LED driver. This is the correct way to drive...

Gonna- I think you are going to need at least 100W of LED power, and probably more, like maybe 150 - 200W for this space. At these levels of light power, you are going to consume a lot of power using a constant voltage power supply as you have shown, vs a constant current power supply...

The most important thing to remember, one that seems to confuse many people, is that it is not the distance that reduces illumination, it is the growth of the spread of the light over this distance, that reduces the ilumination. If you look closely- you will notice that that the same...

ten thirty- good to hear from you. A crow bar circuit would probably be overly expensive and would not accomplish what we want to happen- the LED series string to continue operation with a failed LED in the string. The neat thing about the zener is that, with the exception on NOT...

OK- I have been subscribed to this thread for some time and read new entries every day- I usually keep pretty quiet but I just got to comment on this one- the technical disinformation peddled by these LED companies has to stop somewhere. These 'protection tubes' are NOT resistors- a...

I calculate (roughly) about 138W of actual LED power from the Rhino, based upon their claimed 172W of total power draw (total power minus power supply inefficiencies). So they are running their 3W Osram LED's at about 2W each. For $799.-, this is about $5.78/ Watt, this is a pretty...

Edger9- you are wrong in that raising the temperature of a given space will, in fact, lower the relative humidity. Water vapor 'displaces' the other constituent elements of atmospheric air- warmer air has a higher capacity to hold water vapor because the other elements of the air will be...

It is not possible to lower the Vf (forward voltage, or 'input voltage') of an LED by varying the input voltage. Forward voltage is a function of the materials and process used to fabricate the diode junction (LED die). Forward voltage of an LED at the current state of manufacturing is an...

The term 'Inverter' is synonomous with the term 'Variable Frequency AC Drive'. The AC unit in question uses a 3 phase AC motor, and the efficiency gains as quoted in the advertising come as a result of the ability to run the motor at variable speeds, just fast enough as necessary to do the...