Ventilation ideas for canopy build?

[ozorowsky]

That looks like it's only a digital thermometer with no fan control features...

There are temperature sensitive fan controllers available, this one for example just plugs strait into the fan (you could clip off the female connector and just use the red and black wires, yellow is just a "sense" wire used to measure the RPM of the fan).

Alternatively you could splash a little more cash and get a device designed for a 5.25" expansion bay like this (DVD drive sized slot), which has temp sensors, LCD display, and most importantly custom settings for temperature. I'd be hesitant with this device though as once again there's not a lot said about the operation of it, ideally you'd be able to get hold of it and have a play with it and see if it suits your needs.

Does it need to be automatic? You could get a device like this which has manual control dials for you to adjust the speed as you see fit. Comes with 4 external temp probes (you could put two of these in with your lights, two in the exhaust stream) so you can monitor the temps and adjust as you see fit.

This solution can most likely be a "set and forget" solution. PC fan controllers are usually designed to deal with the variable heat load produced as your use of the PC changes. Your lights will likely come on in the morning, go off in the evening, and stay exactly the same in between those two events. As long as the fans are running I don't see that you'd need automatic speed adjusting. If you have a timer set for your lights, I'd just stick the fans on the same timer so they come on and turn off with the lights.

If it were me, I'd try the fans at full speed first and see if the noise bothered me at all. They'll be running pretty much unimpeded (air impedance and turbulence is pretty much the primary cause of annoying fan noise) in that large hood, if they do bother you then I'd look at reducing the speed. You may find that running them at half speed still provides ample cooling power.

HTH

You got me. This is what I'm doing; going to run a wire between the 4 fans and clip each fan to that wire kind of like a christmas tree in case one of the fans dies/burns out the others dont go out as well.

The main wire I'm going to run to the timer that turns my lighting fans on when the halides turn on.

What I'd like to do for fun/learning sake/another project is to have the timer go to a thermostat of sorts that I can then plug the fans into, so that temperature dependant all the fans will speed up/slow down by themselves.

 

[The Editor]

You'd have to wire them in parallel otherwise voltage wouldn't be split equally.

If it were me I'd just put a splitter plug on the outlet of the timer, plug your lights in to one, then I'd wire up the fans like this using the fan controller listed at the top:

That way if one fan dies the rest still run fine, and all the fans will automatically be run at the same voltage. Should be easy enough to rig up.


EDIT:

Gotta be careful though, the top fan controller I linked has maximum current draw of 0.5A but the fans you have draw 0.3A each. You'd need to either find a meatier fan controller than can take over 1.2A or get a couple of controllers...

EDIT 2:

In fact the fan controller circuit looks like a very simple circuit... If I could remember my old systems and control classes I might be able to knock you up a circuit diagram for it. Alas I don't, but I am confident someone on these forums would know how to rig up a thermistor and power transistor to give you the desired effect... You could order the components and a breadboard on line and put it together yourself in a project box, use variable resistors to custom tune the temp range/fan speeds....

EDIT 3 (I'm on a roll!):

Alternatively (again) you could cancel/retuurn the fans you've bought already, and get some like this, they have temp control circuits build directly into the fan and have an external temp probe. Would do away completely with the controller between the voltage converter and the fans. Auto adjusts fan speed over the range temp range 22*C - 42*C:

Fan Speed (RPM): 750 (22C) - 1500 (42C)

Just a thought, I'll stop editing my posts now....

 

[ozorowsky]

You'd have to wire them in parallel otherwise voltage wouldn't be split equally.

If it were me I'd just put a splitter plug on the outlet of the timer, plug your lights in to one, then I'd wire up the fans like this using the fan controller listed at the top:

That way if one fan dies the rest still run fine, and all the fans will automatically be run at the same voltage. Should be easy enough to rig up.


EDIT:

Gotta be careful though, the top fan controller I linked has maximum current draw of 0.5A but the fans you have draw 0.3A each. You'd need to either find a meatier fan controller than can take over 1.2A or get a couple of controllers...

EDIT 2:

In fact the fan controller circuit looks like a very simple circuit... If I could remember my old systems and control classes I might be able to knock you up a circuit diagram for it. Alas I don't, but I am confident someone on these forums would know how to rig up a thermistor and power transistor to give you the desired effect... You could order the components and a breadboard on line and put it together yourself in a project box, use variable resistors to custom tune the temp range/fan speeds....

EDIT 3 (I'm on a roll!):

Alternatively (again) you could cancel/retuurn the fans you've bought already, and get some like this, they have temp control circuits build directly into the fan and have an external temp probe. Would do away completely with the controller between the voltage converter and the fans. Auto adjusts fan speed over the range temp range 22*C - 42*C:

Fan Speed (RPM): 750 (22C) - 1500 (42C)

Just a thought, I'll stop editing my posts now....

I emailed this guy but REALLY like this fan controller you found My FIance laughed at me, I told her its my first step to making my fish electronic

CPU VGA HDD Speed Fan LCD Temperature Controller for PC | eBay

I would hope that can handle the amperage.

 

[The Editor]

Sweet, I hope it works out for you both the electronic fish and marriage.

^very strange sentence^


There are literally hundreds of variations of that sort of thing on eBay, searching "fan controller temperature" gave me most of the ones I linked to...

This is the start, then it's electronic pH meters controlling CO2 injection... Then it's ATOs built into the sump... Then it's timed auto PWC's... Then it's an auto feeder stocked up a month at a time... Then it's not as if you're even keeping the fish any more, they become completely autonomous...

Then there's a power cut and you sh*t bricks....

 

[ozorowsky]

Then there's a power cut and you sh*t bricks....

LOL thats why I got a battery backup and a float valve so that nothing backs up back into the sump in case the pump dies on me.