- Jul 11, 2001
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I bought a pair of Cooler Master MegaFlow 200 - Sleeve Bearing 200mm Silent Fans in order to cool down my small (~80 square feet) bedroom in warm weather (evenings it's typically 10-12 degrees warmer in the bedroom than the outside temperature when I go to bed, in general in the low to mid-70's, sometimes higher). I made a screen for the window and a fiberboard panel that fits over the screen with cutouts for the two fans. I have the fans mounted so they draw cooler outside-air into the room. I think it's possible that it will be more efficient if I have one of those fans exhausting, don't know, but at least initially they will both draw air in. I'll have a switch next to my bed to turn them on/off.
I'm planning how I power these fans. They come with molex plugs and a molex to hook up to a PSU. I plan to have the fans in parallel and probably powered by one or two wall warts I have. Both of these wall warts are rated 12vdc, 500ma output.
The fans are rated 12vdc, current 0.16A, (Max 0.28 A), power consumption 3.36 W. I figure that one of these wall warts should do the job, but I know it's getting close to the spec, so I'm not sure and I don't know if it's a fire hazard or at least a strain on the wall wart.
I get different readings when I measure output with a digital multimeter:
wall wart 1 (on unit says input 12w): 17.13 vdc reading with multimeter, no load
wall wart 2 (on unit says input 12w, 0.1A): 19.40 vdc reading with multimeter, no load
Should I use wall wart 2? Is it probably "stronger" than wall wart 1? Or should I use one for each fan (more complex hookup), or get another power supply entirely?
I suppose it's possible to have the wall warts hooked up in parallel in the same way that the fans are so the supply would be 12vdc but the current draw would be across both wall warts giving a combined DC draw capacity of 500ma + 500ma = 1A. The total electricity usage would, I figure, be about the same. What do you think?
I'm planning how I power these fans. They come with molex plugs and a molex to hook up to a PSU. I plan to have the fans in parallel and probably powered by one or two wall warts I have. Both of these wall warts are rated 12vdc, 500ma output.
The fans are rated 12vdc, current 0.16A, (Max 0.28 A), power consumption 3.36 W. I figure that one of these wall warts should do the job, but I know it's getting close to the spec, so I'm not sure and I don't know if it's a fire hazard or at least a strain on the wall wart.
I get different readings when I measure output with a digital multimeter:
wall wart 1 (on unit says input 12w): 17.13 vdc reading with multimeter, no load
wall wart 2 (on unit says input 12w, 0.1A): 19.40 vdc reading with multimeter, no load
Should I use wall wart 2? Is it probably "stronger" than wall wart 1? Or should I use one for each fan (more complex hookup), or get another power supply entirely?
I suppose it's possible to have the wall warts hooked up in parallel in the same way that the fans are so the supply would be 12vdc but the current draw would be across both wall warts giving a combined DC draw capacity of 500ma + 500ma = 1A. The total electricity usage would, I figure, be about the same. What do you think?
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