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QW-ms305D setting constant current?

Martaine2005

May 12, 2015
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Hi all, my son’s friend has bought two qw ms305d psu’s amongst other test gear. They are new. He had a problem not being able to set constant current. My son said “my dad will know”!!. I agreed to go there yesterday (Sunday). Well, I d/l the manual in chinglish. I watched several YT vids. I can’t do it!. Manual says to dial in between 3 and 5 volts then short the output leads while dialing in the required current.
I couldn’t get voltage to display without turning the current knob slightly. Then I set the V to 4v. I shorted the output leads and the current led displays. I tried to set the CC but nothing. Display stays at 0.00.
I sheepishly told him to buy better equipment and that I would ask you gents on here. My comment was more embarrassment as I know he can’t afford it being in university with my son. Have you guys got any ideas?.
I almost gave him my old Maplin psu, but thought better of it

Thanks Martin
 

Audioguru

Sep 24, 2016
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Sep 24, 2016
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Look on You Tube for a test of its current regulation NOT WORKING. The test person contacted the seller Who KNEW ABOUT IT NOT WORKING and gave a refund. Cheeep Chinese Junk!
 

Arouse1973

Adam
Dec 18, 2013
5,178
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Dec 18, 2013
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Hi Martin, it's been a while, hope you are well. Got any pics of these PSUs. Ads
 

Martaine2005

May 12, 2015
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Hey Ads, been emailing you for decades it seems..
Yes am well thanks.
I will ask my son to get some pics on his phone. I will try emailing you aagain later. I am back in the UK now. Keep well and hopefully speak soon.

Martin
 

Arouse1973

Adam
Dec 18, 2013
5,178
Joined
Dec 18, 2013
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5,178
Hey Ads, been emailing you for decades it seems..
Yes am well thanks.
I will ask my son to get some pics on his phone. I will try emailing you aagain later. I am back in the UK now. Keep well and hopefully speak soon.

Martin
Hi mate, not been getting any emails. PM me your email and I will respond. Ads
 

Martaine2005

May 12, 2015
4,932
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Quick update here.
I have had another look at these as seller has not responded.
My findings are interesting. Shorting leads for CC null etc.
I turned the heat up and shorted at 9v. A little spark and CC was set. I tried again at 13v, same result.
Seems these SMPS do work albeit differently to the manual. I have warned my sons friend to unplug them when not in use.
Both were accurate with regard to voltage. I only had a hand held DMM with me.

Martin
 
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