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Thread ID: 70260	2006-06-27 03:41:00	What can give 12V at 11.6amps for cheap?	Feelers (10034)	PC World Chat

Post ID	Timestamp	Content	User
466592	2006-06-28 04:33:00	Do you know if the motor is a brush one? Its starting current could be fairly high, and a linear (transfomer + rectifier) will handle that happily . A switchmode might hiccup on it, if it's very large . Unfortunately, a 150W transformer isn't cheap . By the way, a car size lead-acid battery can't provide 10A for 4 hours . The amp-hour rating is at the 20hrs rate . The time available at higher currents is not a linear function . I think the modern rating gives the number of minutes a battery will supply 25A before it reaches its voltage end-point (10 . 5 or 11V) . Taking the battery lower than that will be harmful or fatal to the battery . I still think a mains operated blower is the answer . The ratings on a computer PSU are a guide . The supply will shut down if too much power is pulled, but that is based on the total of all supplies . If you've got a 360W (say, just to make the arithmetic simple) supply, which has a 10A rating on the 12V output, you could probably pull 36A from that supply, if it's the only supply loaded, before the overload protection would operate . The diodes, and the transformer winding would be hot . You might even get some spontaneous unsoldering in the supply . The diodes could pop . Modern power diodes are amazingly tough, but they still don't like excessively high temperatures . But it should handle 10A continuously, if it's the only loaded supply . You might need to have a load on the 5V . . . that's the regulated one, and some say the 5V output is "1 . . x A", meaning that there is a minumum load on it for proper regulation .	Graham L (2)
466593	2006-06-28 05:22:00	i sugest go to an auto sparky, borrow his amp meter and hook the fan up to it and a battery . see what it draws at startup and running . Actually, if he's gonna do that, it would be very important to set the blower up as it's going to run . Amps draw will vary a lot if he's just letting it run on a bench or in a housing . Make sure that the air available to it will be the same as it will in running form too . . and the exhaust area is the same or the amps will be all over the place .	SurferJoe46 (51)
466594	2006-06-28 06:40:00	Well the chances are the motor is 140W, although I will get get it tested to make sure . So whats this about bursting into flames? For example . . . . . would this work? . trademe . co . nz/Computers/Components/Cases-power-supplies/Power-supplies/auction-61467779 . htm" target="_blank">www . trademe . co . nz I know a 350W power supply is 350W total, but I am going on the premise that 12V at say 15Amps from one of the cables would be ok? Could I wire both VDC1 and VDC2 together?	Feelers (10034)
466595	2006-06-29 02:50:00	The 12V, 17A supply of that PSU should be OK. You might need to hang a 5 ohm, 10W, resistor across the 5V supply for stability. The 17A should be a "continuous" rating and the supply will be well withing its rating. That's certainly a better approach than paralleling independent supplys.	Graham L (2)
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