Why wont this adapter power my fan?
- Thread starter jawilson20
- Start date
Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:
samc
Well-Known Member
Are you sure the adapter is putting out power? Do you have a meter to test it? And do you know for sure the fan works?
OP
OP
jawilson20
Well-Known Member
No to both questions. This is so frustrating!
noggins
Well-Known Member
you gotta plug it in
HAH! I dunno, more than likely one of the items is bad, it's a pretty simple connection and no reason it shouldn't work as long as both items are good, the adapter is probably more likely to go bad than the fan as there are a lot more components involved.
HAH! I dunno, more than likely one of the items is bad, it's a pretty simple connection and no reason it shouldn't work as long as both items are good, the adapter is probably more likely to go bad than the fan as there are a lot more components involved.
OP
OP
jawilson20
Well-Known Member
But the voltage/amps of each device are correct?
noggins
Well-Known Member
yep, 12v is what you want, and .5 amps is enough for a .16 amp fan. Did you buy both items new?
OP
OP
jawilson20
Well-Known Member
Yeah I did. I read somewhere that the fan is polarity specific, I am wondering if I initially hooked it up backwards.
noggins
Well-Known Member
polarity specific should just mean if you hook it up one way, the fan will spin one direction, and switch directions when hooked up differently.
Not sure if this is correct but the fan might "spin" with a 9v battery, at least you can check if the fan goes and concentrate on the adapter.
Got any 12 V lamps (car lights, etc.) and you can check the adapter.
Got any 12 V lamps (car lights, etc.) and you can check the adapter.
OP
OP
jawilson20
Well-Known Member
So the 9v battery does power the fan. However, it is only in one direction. When the red wire is attached to the positive it works. When I reverse the connection, nothing.
I am wondering it I somehow fried the ac adapter by attaching it backwards initially. If so, how do you identify the positive wire on the AC adapter?
I am wondering it I somehow fried the ac adapter by attaching it backwards initially. If so, how do you identify the positive wire on the AC adapter?
OP
OP
jawilson20
Well-Known Member
If I need to buy another adapter, is the 12v 500ma the best option? Or should I look at other power options?
I doubt you would have fried the adaptor. Is the adaptor 12VDC output? It does not specify in the photo. If its AC, It may not work. You can bare the adaptor output wires and short them briefly you should see a little spark if its working...a meter would be better.
OP
OP
jawilson20
Well-Known Member
It is a 12vdc ac to dc power adapter.
- Joined
- Nov 6, 2007
- Messages
- 62,016
- Reaction score
- 6,922
sounds like your supply is no good. I'd say take it back, but would check it with a meter first.You can pick up a cheap one at the Shack.
OP
OP
jawilson20
Well-Known Member
Looks like that is what I got to do. Should be fun returning a adapter with the end cut off.
- Joined
- Nov 6, 2007
- Messages
- 62,016
- Reaction score
- 6,922
They're not going to except it. Sorry. If this is the only project you're likeyl to ever do, you'd be better off saving the money on the new stuff and just buying a stir plate with lifetime guarantee over at stirstarters.com for $42
OP
OP
jawilson20
Well-Known Member
This is for a draft tower fan.
- Joined
- Nov 6, 2007
- Messages
- 62,016
- Reaction score
- 6,922
Oh, my mistake. Next power adapter, touch the fan leads to the output before cutting the adapter. The adapter package should say if the outside of the post of the inside is ground or positive.
jawilson20 said:
Unlikely. I identify the wire simply by testing it out, and it's worked every time for me with several adapters. If I connect them backwards to the switch, I just change them around.
jawilson20 said:
It depends on the specs of the fan you're using, in particular amperage/wattage, and in some cases, start-up amperage. Unless it's a powerful fan though, there probably won't be an issue. I use a really good computer fan that would start up and die every few seconds with even a 1000ma (12W) adapter, and so I actually ended up using a 2-piece laptop power supply! But that's overkill.
OP
OP
jawilson20
Well-Known Member
Just an FYI to everyone. The issue was the fact that the fan was polarity specific. By hooking it up backwards initially I fried the AC adapter. Now it is rocking and rolling with a new adapter. Thanks everyone for help in the troubleshooting.
that's strange. I've hooked an adapter up to a fan backwards, and the only thing that happened was that the fan didn't spin. Flip the wires and all was well.
OP
OP
jawilson20
Well-Known Member
Who knows. I bought a new adapter and a multimeter. Used the multimeter to identifty the positive wire and the connected the positive wires and it worked. Don't want to take my chances switching it to test my theory!
Hang Glider
Beer Drinker
also, on those wall warts, the wires are usually marked in some way - a light grey dotted line on one side of the wire indicates ground, usually.
I'm with Walker - mine never fried the adapter - just changed the wires around and all is well.
but yeah, some of those fans won't spin backwards (polarity specific)
I'm with Walker - mine never fried the adapter - just changed the wires around and all is well.
but yeah, some of those fans won't spin backwards (polarity specific)
MOST computer fans won't spin backwards. I have all sorts of them, and none of them will. I've also switched the wires around on them, with both a wall wart and even a 90W (or more accurately, 54W/4.5A when set to 12V) sectional laptop adapter, without frying anything. And there's absolutely no reason it should fry anything.
Of course, I'm careful to always make sure both wires stay isolated. It's possible a few errant strands could have touched and shorted the thing though...
The packaging for my wall-wort did indicate which wire was which, with a marking on the adapter at the end of the wire. After cutting the tip off though, I still ended up getting it wrong but it was no big deal because I knew that connecting the wires backwards wouldn't be an issue. My laptop adapter wasn't labeled though, and rather than having the wires side by side, it was one inside the other, separated by a nylon sleeve (the outer cable being a bunch of wire strands braided as a hollow cylinder around the nylon sleeve.) That configuration made it a lot more difficult to split the wires and keep them isolated, but I managed. I figured the outer wire would logically be neutral, but I got that wrong as well, so it also was originally connected backwards. Again, no issue.
Of course, I'm careful to always make sure both wires stay isolated. It's possible a few errant strands could have touched and shorted the thing though...
The packaging for my wall-wort did indicate which wire was which, with a marking on the adapter at the end of the wire. After cutting the tip off though, I still ended up getting it wrong but it was no big deal because I knew that connecting the wires backwards wouldn't be an issue. My laptop adapter wasn't labeled though, and rather than having the wires side by side, it was one inside the other, separated by a nylon sleeve (the outer cable being a bunch of wire strands braided as a hollow cylinder around the nylon sleeve.) That configuration made it a lot more difficult to split the wires and keep them isolated, but I managed. I figured the outer wire would logically be neutral, but I got that wrong as well, so it also was originally connected backwards. Again, no issue.
Yeah my bet would be on the original adapter was DOA (can't see hooking it up backwards killing it, all they really are is a stepdown transformer and 4 diodes), bit stink you found after you chopped the plug off 
Glad it is up and running though
Glad it is up and running though
rollinred
Well-Known Member
Yeah, your transformer/adapter was bad from the start.
The fan can not fry the adapter, only the other way around if say you hooked up a 24v to a 12v fan.
The fan can not fry the adapter, only the other way around if say you hooked up a 24v to a 12v fan.
Why not just get a 120V fan?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330519584575&ssPageName=STRK:MEWNX:IT
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330519584575&ssPageName=STRK:MEWNX:IT
another thing to look out for... i have seen a lot of wall transformers with non-serviceable fuses inside them (non-serviceable because the plastic case is sealed). I'm not saying that adapter had a fuse, but its possible that if it did, and you shorted the wires a tall, then it was boned.
It can be a hassle to have to throw out the adapter because of that, but blowing a fuse is better than melting wires (and the associated fires that could happen), and if they made the fuse serviceable, it would bump up the cost.
just my thoughts.
--edit--
also, it says int he manual for that thing:
If this adapter is not compatible with the voltage and
current requirements of your portable device, it can result
in PERMANENT DAMAGE to the device
so, even without a built in fuse, if you short it, its done.
It can be a hassle to have to throw out the adapter because of that, but blowing a fuse is better than melting wires (and the associated fires that could happen), and if they made the fuse serviceable, it would bump up the cost.
just my thoughts.
--edit--
also, it says int he manual for that thing:
If this adapter is not compatible with the voltage and
current requirements of your portable device, it can result
in PERMANENT DAMAGE to the device
so, even without a built in fuse, if you short it, its done.
mattmauriello said:
Yeah, in a post a while back, I figured it was a short. Especially if you're hooking up the stranded cables directly to the switch (which typically have the contacts extremely close together) it's pretty easy to have some stray wires touching each other once the cables are stripped, if you're not careful.
