long strings

i13

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That's one that I don't know about.

Try asking the seller if it can handle higher voltages; it wouldn't surprise me if it could but you'd still be taking a risk. There are plenty of controllers that can although you might have to buy one within Australia to get it in time for the season.

It might depend on what part of the board gives up first but if the mosfets can handle it then you have the option of example 2 here. I'm not 100% sure about whether this will damage your controller but I'd expect that only the mosfets would handle the higher voltage.
http://auschristmaslighting.com/wiki/Controller_Setups_and_Settings

I'd be interested to know the result as this controller could be a good find.
 

strangesparks

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Thanks for all the help.


I've asked the question of the supplier, he's said they would test it with a higher voltage and get back to me asap... still waiting.
I've gone ahead and ordered a 36V supply anyway, because I will need one unless anyone can give me a simple circuit to boost 24VDC into 32VDC?


next noob question... even if I can push the higher Voltage through the DMX board, I will only have on/off control anyway?
Thinking behind this is that these Lights are dimmed via Pulse width modulation and the DMX system is just too slow to do this? or will they dim to some extent via straight voltage dimming?


Thanks
 

AAH

I love blinky lights :)
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Without knowing the actual board in question I would hazard to guess that they use the traditional PWM dimming method used on pretty well all DC dimmer boards. The dmx packets feed the board with a 0-255 brightness level and the board converts that to a PWM output at 100's to 1000's Hz at a variable on/off ratio.
 

i13

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36V might be too high depending on how much the supply voltage can be wound down. You can use diodes to compensate for a higher voltage so it isn't an enormous mistake; you'll just have a slightly higher power consumption and need more diodes lined up. The reason I suggested asking about higher voltages is the 27 channel controller is a common example that can handle up to 35V even though it is labelled as 12-24V.

Answering your question, it is the other way around. If you can power the lights through the controller then yes you can dim them. If you can't power them through the controller and decide to use relays then no you can't dim them.
 

strangesparks

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Great, I am now assuming/hoping that this board is following the convention with pwm.

This board came with instructions for 5v lights, with a 5V and 12V for the board. the negatives are joined but the 5V +ve bypasses the board to the common on the string.
My question is if this might work for the higher Voltage?
 

strangesparks

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i13 said:
That's one that I don't know about.

Try asking the seller if it can handle higher voltages; it wouldn't surprise me if it could but you'd still be taking a risk. There are plenty of controllers that can although you might have to buy one within Australia to get it in time for the season.

It might depend on what part of the board gives up first but if the mosfets can handle it then you have the option of example 2 here. I'm not 100% sure about whether this will damage your controller but I'd expect that only the mosfets would handle the higher voltage.
http://auschristmaslighting.com/wiki/Controller_Setups_and_Settings

I'd be interested to know the result as this controller could be a good find.


I think I'm going to go for 'option 2', which is what I was alluding to in my previous post. From what I can see the Mosfets can take up to 60V so no problems there. There is the risk in the voltage straying into the rest of the board, but I'll just have to take that risk. I've got a DC-DC voltage booster on order, its left china so "should" be here in time for the initial switch on.


Sorry, I'm just thinking out loud here, but feel free to correct my thinking.
 

i13

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Thanks for posting about your success. Check the current draw so the LEDs don't get damaged. For each channel it should be 10mA multiplied by the number of series sections in it. These are the thick sections between the points at which the light set has only three wires plus the end which often only has three wires.
 
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