Stupid fan wiring...

[mike31154]

Originally Posted by Myka

As long as I know which wires do what, I'll be fine. The only reason this isn't completed yet is because B&E isn't open on the weekends. I can't believe how hard it is to find a simple 12VDC power supply these days!

You don't have a Can Tire or Wal Merde in Saskatoon? $s to donuts they'll have a 12 volt wall wart. They will probably also have a cheap digital multi-meter for sale. A useful tool for figuring out polarity, i.e. which wires do what. You're not really going to hurt anything with 12 volts DC if you get the polarity wrong, especially with the 9 volt battery scenario. If you reverse the polarity, the fan will either run in reverse or not at all. LEDs as well, they are essentially diodes, so correct polarity, they'll conduct (light up), reverse polarity, they won't. You'd have to apply a very high voltage to cook them in reverse polarity.

[Myka]

Originally Posted by mike31154

You don't have a Can Tire or Wal Merde in Saskatoon? $s to donuts they'll have a 12 volt wall wart. They will probably also have a cheap digital multi-meter for sale. A useful tool for figuring out polarity, i.e. which wires do what. You're not really going to hurt anything with 12 volts DC if you get the polarity wrong, especially with the 9 volt battery scenario. If you reverse the polarity, the fan will either run in reverse or not at all. LEDs as well, they are essentially diodes, so correct polarity, they'll conduct (light up), reverse polarity, they won't. You'd have to apply a very high voltage to cook them in reverse polarity.

Neither Crappy Tire nor Wally's had a 12VDC power supply. So you owe me donuts!!

[GoFish]

First thing that comes to mind when looking for 12vdc power supply would be "surplus" section in princess auto. Looks like you have one in Saskatoon
Sorry havent read the rest of the thread or if this will help.

[Myka]

Originally Posted by Vancity

First thing that comes to mind when looking for 12vdc power supply would be "surplus" section in princess auto. Looks like you have one in Saskatoon
Sorry havent read the rest of the thread or if this will help.

I tried there too. They had one 12VDC, but it was 3A with alligator clips on it.

I'll get to B&E sometime this week.

[mike31154]

12 volt 3 amp with alligator clips! That would work great. Just because you only need 1400 mA, doesn't mean a 3 amp power supply can't be used. It will only supply what the fan draws, no more. Better to have a larger supply working at 15-20% than a smaller one at 90%.

[MKLKT]

Just as an FYI, I'm pretty sure the yellow wire is strictly RPM/monitoring, doesn't actually control anything. I remember having red/black molex fans with fan control.

[Myka]

Originally Posted by mike31154

12 volt 3 amp with alligator clips! That would work great. Just because you only need 1400 mA, doesn't mean a 3 amp power supply can't be used. It will only supply what the fan draws, no more. Better to have a larger supply working at 15-20% than a smaller one at 90%.

Oh really? I didn't realize it would only draw what it needed. I got one from B&E that is 1500 mA.

Originally Posted by MKLKT

Just as an FYI, I'm pretty sure the yellow wire is strictly RPM/monitoring, doesn't actually control anything. I remember having red/black molex fans with fan control.

I am going to have to experiment because the wires are not colored, they have clear coating on all of them.

One of these days I'll have enough time to get back to this project as well as actually getting the tank running!