Diy Led Rig

[StandbySetting]

I found a 24V 750mA PSU tonight so all is good, thanks for all of your help, I really appreciate it

 

[StandbySetting]

The driver came today, and it was advertised at 700mA, but on the packet it says 688mA I'm just hoping that this is enough current to power the LED's, or will they just run at less power?

 

[SuperColey1]

That will be fine. Mine are 650. If you run at lowre than Max then the LEDs will last longer still. There is of course a point where they rapidly go from being very bright to very dim but 688 you nor the plants will notice a difference other than they will last longer

Andy

 

[StandbySetting]

Thanks Andy, the unit should be built some time next week, I just need to pick up thermal pads and a transformer.

 

[StandbySetting]

One thing I'm still not sure on is the transformer I need, here's on on ebay:

http/www.ebay.co.uk/itm/AC-100-240V-Converter-Adapter-DC-24V-1A-Power-Supply-UK-/220820854326?pt=UK_ConsumerElectronics_PowerAdaptors_SM&hash=item3369f2d636#ht_1816wt_905

Everything looks fine, but it's just the power output that worries me, do I need to consider this, the power output of this transformer is 24W, Will the LED's draw what they need? Or do I need to consider the Power output of the adapter when buying one?

Ignore the above post, I've just remembered a Physics calculation I learned as part of AS Physics, P=VI so the wattage of the adapter = Voltage x Current, 24V*1A = 24W lol.

 

[SuperColey1]

You've lost me on the above physics blarb.

All I can say is 24V minus 1.5 for the driver = 22.5V which leaves 3.75W for each of the 6 LEDs (minus resistance from the wires and other parts) which is exactly in the boundaries.

Maybe I'm wrong but that looks perfect maths to me

Andy

 

[StandbySetting]

Thanks Andy, one final question however, I know that positive always goes to negative, but am I right in thinking that the positive terminal on the driver goes to the positive side of the LED? And then the negative to negative? I'd hate to go and blow the lot so thought I'd ask before hand.

Here's a diagram of the circuit as it stands:

Soldered up:

 

[SuperColey1]

If I remember rightly you are right + fromt the driver to + on the first led, then it out of - to the + on next led etc.

I can't take a look at mine because the star is sandwiched between the heatsink and lense holder. I dabbed superglue on the edges of the lense holders just to make doubly secure. lol

Andy

 

[StandbySetting]

OK, thank you, I just have to build the housing and wait for the PSU now, on the driver input it says VIN and GND, I presume that the GND (ground) is what I use as the negative terminal and VIN as the positive?

 

[SuperColey1]

OK, thank you, I just have to build the housing and wait for the PSU now, on the driver input it says VIN and GND, I presume that the GND (ground) is what I use as the negative terminal and VIN as the positive?

no idea mine just had the + and - me thinks. the spare one was for dimming

Andy

 

[StandbySetting]

Ok, I'll have to email the seller, thanks.

 

[Ps3Steveo]

Just so you know for power supplies and cooling you could look into security system power supplies, some are so cheap, come with built in thermostats can be switchable 12/24v, have dials for upping and lowering amps and some even use adjustable thermostats so you can use them for cooling the unit and the lighting, I have an all singing all dancing 1 amp psu sitting in my shed I paid £12 for. If your good with electrical equipment you could break it down and pretty much use all of it to build a lighting unit other than the mounting and L.E.D's.

I may have to start building and selling these they're that easy.

 

[StandbySetting]

Thanks PS3Steveo, I'll have to look into them, I have ordered a PSU from Hong Kong, a 24V 1A transformer, if it's no good I'll look into one of those.

 

[Ps3Steveo]

No worries if you have any questions let me know, been doing electronics and electrics for 12 years.

 

[Aqua Tom]

You have wired the LED's in series, which is fine & will work well. I would personaly wired them in parallel simply because if one LED blows or you get a bad joint then none of the lamps in a Series circuit will work (think old fashiond xmas lights).

In parallel this doesnt happen & only the faulty LED will not work, this helps faultfinding no end.

Tom.