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 Post subject: VRM test procedure
PostPosted: Sat Nov 10, 2018 9:04 pm 
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Joined: Wed Sep 19, 2018 12:47 pm
Posts: 21
I was getting frustrated today. I had convinced myself that my VRM install had gone wrong somehow.

Mr Cohrs suggested that I try this test procedure. A 9 volt battery. Alligator clip jumper from the battery negative to a ground lug, and get your negative multimeter probe stuck in this same alligator clip. Then put another jumper from battery positive to the B+ in on the VRM.
Put your positive multimeter probe on the VRM's B+ out tab.
Twist the dial on your VRM.

I got about 5.9 volts with the VRM twisted up to max, and down to zero turning the VRM the other way.

One caution: it doesn't start responding normally right away. I think something in the mosfet must need to build up a charge because initially, there's no response at all. Then for a while the voltage change is delayed - you turn up the VRM, and the voltage readout on your multimeter just ssllooowwwllyy starts to increase. After a few times through, it responds immediately.

Thanks Mr Cohrs for this cool test procedure.
I had driven myself crazy imagining there was a problem, then I couldn't figure out my imaginary problem :roll:
This quick test demonstrated that the problem was just in my head, not in the VRM.

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 Post subject: Re: VRM test procedure
PostPosted: Thu Dec 13, 2018 10:46 pm 
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Joined: Wed Sep 12, 2018 5:17 pm
Posts: 374
Location: Shawnee, OK
This was an immense help when I finally installed VRM in my first Trinity build (Tweed). Thanks for posting it!

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 Post subject: Re: VRM test procedure
PostPosted: Fri Dec 14, 2018 10:03 am 
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Joined: Sun Mar 13, 2005 4:10 pm
Posts: 7519
Location: Canada
Weve incorparated it into the manual now! Thanks for being the guinea pig!

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Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps


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 Post subject: Re: VRM test procedure
PostPosted: Fri Dec 14, 2018 1:51 pm 
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Joined: Wed Sep 12, 2018 5:17 pm
Posts: 374
Location: Shawnee, OK
When I was testing my VRM install, I was getting readings that were all over the place on the multimeter. Then I remembered this thread! Got me past the fear of having done something wrong on the install.

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"The only problem with being retired is you never get a day off"


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