Can't find a 10V wall adapter for the life of me...

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Antilogical

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#116366 26-Apr-2013 21:14

Ahh! I'm pulling my hair out over this. I have searched for hours and have yet to find a simple 10V DC wall adapter... that's all I need. One silly wall adapter. I can find 9V & 12V ones, even a 10.5V one, but nothing at exactly 10V. I need one to provide a reference voltage for an LED driver, and the specifications require a 10V source... so that's what I'm looking for. I've tried element14, jaycar, tradeMe, ebay, etc.

I can find dozens of American 10V adapters, but none that fit our stupid plug type. Just...

...nothing. Anyone know where I might be able to pick one up from? Thanks. :)

Regs

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Snowflake

#806127 26-Apr-2013 21:24

does it have to be exactly 10v? will the LEDs just be a little dimmer with 9v, or a little brighter at 12v?

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mjb

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#806128 26-Apr-2013 21:24

What's the power supply of your LED driver?

How much current does the reference input sink?

Build a voltage divider.

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timmmay

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#806142 26-Apr-2013 22:14

Google sicom

Antilogical

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#806150 26-Apr-2013 23:05

Regs: does it have to be exactly 10v? will the LEDs just be a little dimmer with 9v, or a little brighter at 12v?

Can't be sure... the documentation (it's a Meanwell LPF-90D-54) merely mentions it accepts a 10V reference voltage, and with a 10K/100K potentiometer you can adjust the voltage to 1-10V for 10%-100% brightness respectively. I'm sure a 9V wall plug would work just as well but I'm really wanting to push the full 100% brightness here.

I wouldn't really be willing to push it to 12V...

mjb: What's the power supply of your LED driver?

How much current does the reference input sink?

Build a voltage divider.

The dimming wires (DIM+, DIM-) are on the output side of the driver with the LED+ & LED- wires. Input wise it accepts 0.5A @ 230VAC. The dimming wires have to be powered separately however, thus the need for a reference voltage.

I can't be sure how much current is used for the reference, the stores which sell the driver and (American) plugs are rated for 1A-500mA output @ 10V DC.

How do I do that and how would I connect a homemade voltage divider to the mains?

mjb

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#806152 26-Apr-2013 23:19

You don't want to build a voltage divider to connect to mains - it's for DC, not AC.

Reading the spec sheet, you should just be able to use a pot, rather than voltage. It says 'resistor OR 1-10V'.

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Antilogical

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#806157 26-Apr-2013 23:25

mjb: Reading the spec sheet, you should just be able to use a pot, rather than voltage. It says 'resistor OR 1-10V'.

Ahh! I just found this out myself... yes - you're completely right. All the resources I've been reading on the net seemed to indicate that a 10V ref. was required in addition to a 100K potentiometer, but it seems the LPF-90D series has a 10V voltage on the DIM+ wire anyway. The resources I was reading was for the LPF-60D series which is slightly lower spec. Thanks!

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#806224 27-Apr-2013 08:18

MeanWell makes good quality supplies. So all you need is a 100k linear pot (not log). Nice that it supports a pot, voltage, or PWM.

You can never have enough Volvos!