- #36
sophiecentaur
Science Advisor
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The best value of cooling effect from ice would probably involve local cooling of the driver's body with partially insulated ice packs inside the driver's clothing.
OmCheeto said:The sun decided to burst out early today.
Currently collecting preliminary data.
jim hardy said:two tons of refrigeration,
a ton of refrigeration being able to make a ton of ice in a day
which is 83.3 pounds in an hour
It's been my rule to never to pay more than $20 for equipment for an experiment, unless I've done the maths first.iduhfuse said:Update: Canada Post is going on strike and therefore my rad is being delayed. Son of a gun! It might be a while until you hear from me next but don't worry. There will be pics and all. Also, cig lighter is 15amps. That's easily enough to power my pump 3A + 2, 0.5A fans. Total 4 amp draw lol.
Seriously?Planobilly said:No pun intended
Seriously.Planobilly said:Win, loose, or draw, it is always fun!
You think water shorted the fans? *Cries*Tom.G said:Methinks the H2O entered the prime air mover. (At least that's better than the brown stuff entering the air conditioning system.))
iduhfuse said:Fans 7-12V rated at 0.5 Amps
I checked system running at 12.36 volts (car off) with multimeter. The fans are Corsair SP 120 High performance. Also can you send me a link for a flywheel diode?...i'm seeing diagrams. I have no idea what that looks like lol. OOPS ****Another thing I forgot to mention. I did remove the pump from the circuit and tested each fan individually. They both did not work.jim hardy said:Got a datasheet for those fans ? Any notes in it about mounting plane ? Are they brushed or electronic ?
12 V ? Car runs 14, surely they're not that tender.
However - inductance of water pump could be generating a turn-off transient...reverse polarity spike when you flip the switch off
one of those cheap bicolor LED voltage testers would probably show, look for a green flash at turnoff
http://www.walmart.ca/en/ip/auto-voltage-tester/6000119380174try a flywheel diode ?
old jim
iduhfuse said:Also can you send me a link for a flywheel diode?...i'm seeing diagrams. I have no idea what that looks like lol.
Damn, I understood about a 1/4 of that hahaha. I will wait tomorrow until fans are completely dry. Who knows, maybe water did get into them (I'm hoping not) the rad wasn't even condensating yet but oh well. If the fans are shot, there goes $40...any other alternatives to push air through the rad?rbelli1 said:Don't bother with the 1N4001 diodes. Get 1N4007. They are 1000V and usually the same price as the 50V ones. If you ever need the higher voltage then you already have them. Get a bunch. Almost anywhere something just specifies a diode without any more information they will work.
For series diodes you will get better performance with Schottky diodes. It probably doesn't doesn't matter in this application but the lower forward voltage is useful for higher currents and applications where the voltage drop could be problematic. Don't use them for half wave rectification. The reverse leakage current is bad for polarized capacitors. And a bigger capacitor doesn't help. Or at least so I've been told !
BoB
sorry - heat of the chaseTom.G said:I see you beat me to it Jim.
Tom.G said:What say, Jim?
If there were 50V or 100V spikes etc... would that not blow my 8A fuse I wired into the circuit.Tom.G said:I just realized that 50V spikes are common in car electrical systems, and I wouldn't be suprised to see an occassional 100V spike. If those fans are the common 12V units sold for computers, they are brushless DC. The IC in them seems to be a Hall detector and commutator all in a 3-pin TO-92 package. Those would definitely need surge suppression/filtering on the power leads. The question is, what would be the most appropriate? Perhaps back-to-back 16V 5W zeners with a low amp fuse on the incoming power? What say, Jim?
@iduhfuse If the fans are dead, don't trash them. A post mortem would be helpful. Specifically, If there is an IC or transistor in them, let us know the part number and other markings on it. That way we can look for a data sheet and find out what their voltage rating is.
I like the idea of this, but if I'm understanding this correctly...the idea is my fans would not be getting power? However, when the pump is out of the circuit they don't function. So, in addition to this possibility I think I have another problem elsewhere...Only data I got on the fans are that they are 12V at 0.25 Amps.jim hardy said:Don't forget that inductive kick reverses polarity.
When the switch opens
instead of current being pushed through the pump motor by the battery
the pump motor now tries to suck current through the switch, which of course it can't, and the only place it can get it from is backward out of the fans.
A motor's inductance can make a lot of voltage trying to do that.A flywheel diode let's the motor suck current , harmlessly circulating it around through the diode, with only one diode drop (-0.6V) which won't hurt anything.
View attachment 103197
https://www.westfloridacomponents.com/blog/what-is-back-emf-and-what-does-it-do/
old jim
All I could find on the fans here: http://www.corsair.com/en/air-series-sp120-high-performance-edition-high-static-pressure-120mm-fanTom.G said:I just realized that 50V spikes are common in car electrical systems, and I wouldn't be suprised to see an occassional 100V spike. If those fans are the common 12V units sold for computers, they are brushless DC. The IC in them seems to be a Hall detector and commutator all in a 3-pin TO-92 package. Those would definitely need surge suppression/filtering on the power leads. The question is, what would be the most appropriate? Perhaps back-to-back 16V 5W zeners with a low amp fuse on the incoming power? What say, Jim?
@iduhfuse If the fans are dead, don't trash them. A post mortem would be helpful. Specifically, If there is an IC or transistor in them, let us know the part number and other markings on it. That way we can look for a data sheet and find out what their voltage rating is.
iduhfuse said:I like the idea of this, but if I'm understanding this correctly...the idea is my fans would not be getting power?
Hi Jim, yes you're correct. I still need to make a 3 inch hole saw cut to vent in air otherwise negative pressure builds in the cooler.jim hardy said:Looking at post #46
it is not clear to me how air will circulate through your radiator... Both fans point same way ? They can't pull air out that didn't get in someplace...
What did i miss ?
old jim
Or you could physically reverse the direction of one of the fans.iduhfuse said:Hi Jim, yes you're correct. I still need to make a 3 inch hole saw cut to vent in air otherwise negative pressure builds in the cooler.
Jesus Christ, at that point I'd buy a new car with AC lolOmCheeto said: