twin MC-E build (when arrives from cutters :) )

[tayse8]

First post on here but been reading all your posts with envy for a long time.

MY BUILD:

2 * MCE Cool white LED's on round 20mm pcb (when it arrives from cutters)

1 * Plain tight 26.5mm lens

1* Frosted medium 26.5mm lens

housing is going to be copper tubing with a moddified p3 heatsink stuck on top to fit inside some old lights (sounds messy but will post pics once complete)


Plan is to run each MC-E as 2s2p resulting in 6.4v 700ma on low (7v 1.4A high (if can find driver at which can go from 700ma-1.4A))

now my sticking point....:shakehead

I want to be able to either dim both lights or switch one off when not in use (parrel is best for this right?). to do this I will need 2 drivers one for each MC-E right?? Was thinking of using a bflex as its thermal sensors would come in handy.

WHATS the expert opion on driving 2 MC-E and what combination would you use?

power will come from any number of combinations of 2.5A nimh AA's.

(current rig is 20w spot + 30w flood halogens overvolted at 13.2v + 33batteries hence me changing to LED's :thumbsup

 

[StevelKnievel]

You could run the two MC-Es in series with each one setup 2s2p and drive it with a single maxflex and 10 NiMH AAs in series. The maxflex can put out 1.2A and has thermal protection. It should be over 1200 lumen on high with that setup. Runtime would be around 1.5h on high, which is fine because you'll only need to use the lower settings most of the time.

 

[tayse8]

well still no arrival yet and been doing some more thinking.

Going to use the Bflex driver from Taskled as it has great functions, the rest is the same, its just the layout

each dieeach die each LEDeach LED dual leddual leddual ledmahvflayouttotal mahtotal vf configurationtotal mahtotal vflumen3503.2 2s2p7006.4 2p14006.49127003.5 2s2p14007 2p2800715803503.2 2s2p7006.4 2s14006.49127003.5 2s2p14007 2s14001415803503.2 4s35012.8 2p70012.89127003.5 4s70014 2s7002815803503.2 4P14003.2 2p28003.29127003.5 4P28003.5 2s280071580

whats the best configuration? im thinking each mc-e 2s2p then run in parrel so the volts stay roughly the same. but the amps do jump. this will then run off a 11.1v lion which are quite cheap.

I would prefer the amps to be lower by running them in serries but will the bflex handle going from 1.4a 6.4v to 1.4a 14v? this would then have to be run on a 18.5v lion based on http://www.batteryspace.com/index.asp?PageAction=VIEWCATS&Category=894

what do you guys think are best as some of you must of recieved the mc-e by now?

 

[tayse8]

hmm looks like my cc and paste skills are not great, below is a link to the table of different settings, my new preferred setup is mce 4s then place them in parrel think i will need an 18v lion? which is a tad expensive


http://img253.imageshack.us/my.php?image=lightsml1.jpg

 

[StevelKnievel]

That's why the maxflex is nice. You only need a 7.4v or 11.1v li-ion pack then.

 

[tayse8]

I do see your point with the maxflex, the problem would then be dispersing the heat generated by the maxflex details below, this would be worse with a 7.4v?. I think using a fresh 11.1v lion will be higher than the vf causing problems. not as easy as planned.

Power_output = Vf * Output_current 14*1.2

Power_input = Power_output*eficiency 16.8*0.12

heat diserpation is 2.016 Watts thats more than the 1W recomened, am I correct in thinking that this would not work. housing is in copper endcaps wil copper backing and aluminium heatsink on top.