Thanks, that would be brilliant!
I have found a large, 120mm sleeve bearing fan, which runs on 12V and draws only 0.22 Amps in air. It is made glass reinforced and has a very good life span (obviously in a computer and underwater I would expect failure a lot sooner).
http://www.rapidonline.com/productinfo. ... ef=37-0667
Looks good to me, going to be ordering one very soon, AND it is extremely cheap for a thruster!
Computer Fans
Re: Computer Fans
pscg,
what type of computer fan was that? all of the one I've seen have visible pcbs in the hub for the speed control with absolutely no sealing.
I'd also be worried about getting more than an amp through the tiny wires that computer fans usually have attached to them.
what type of computer fan was that? all of the one I've seen have visible pcbs in the hub for the speed control with absolutely no sealing.
I'd also be worried about getting more than an amp through the tiny wires that computer fans usually have attached to them.
Re: Computer Fans
It seems like a normal computer fan, no fancy stuff. Not sure about the ratings but i think that is 12VDC - 0.34A (I destroyed the label while trying to open the shielded cap for the fan bearing. Fan diameter is 100mm.
I tried it many times underwater (although in fresh water) and it doesn't seems that has any problem with that. Electronics board is shielded (haven't seen any other computer fan with that "option", mmm.....). Also, the cables are capable of 2 or 3A. For the "normal" computer fans, it looks very simple to shield it. I have not made it yet but i'm sure that it can be done.
@AHarris: The only problem that computer fans have is that the ESC board rotates them in only one direction. For a ROV, it takes 3 blidge pumps to control it at every direction (up, down, left, right). So, you will need at least 6 computer fans to control it in the three dimensions (2 for each dimension). This is the reason that in my ROV (currently in work bench - awaiting LED's and 2 12VDC - 0.5A motors with brushes) i could not use computer fans - space problems. It is difficult but not impossible.
I tried it many times underwater (although in fresh water) and it doesn't seems that has any problem with that. Electronics board is shielded (haven't seen any other computer fan with that "option", mmm.....). Also, the cables are capable of 2 or 3A. For the "normal" computer fans, it looks very simple to shield it. I have not made it yet but i'm sure that it can be done.
@AHarris: The only problem that computer fans have is that the ESC board rotates them in only one direction. For a ROV, it takes 3 blidge pumps to control it at every direction (up, down, left, right). So, you will need at least 6 computer fans to control it in the three dimensions (2 for each dimension). This is the reason that in my ROV (currently in work bench - awaiting LED's and 2 12VDC - 0.5A motors with brushes) i could not use computer fans - space problems. It is difficult but not impossible.
Re: Computer Fans
A good point there, I shall look into it further and do some space and power calculations.
Thanks again for all the answers guys!
Thanks again for all the answers guys!
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Alaska Rov Systems
- Posts: 69
- Joined: Dec 6th, 2010, 6:24 pm
Re: Computer Fans
Just to let you guys know, computer fans will work in fresh water only, if you wanted to run it in seawater it would have to be water tight or it would immediately short out. Plus I am not sure about the rusting factor. I will have to experiment and research it. So far i took a 12 volt 0.25 amp computer fan and ran it successfully in fresh water on 22 volts DC at 500 ma. it ran because the amperage did not go over the limit of the motor.
Alex
Alaska ROV Systems
Alex
Alaska ROV Systems