Welcome
Username or Email:

Password:


Missing Code




[ ]
[ ]
Online
  • Guests: 28
  • Members: 0
  • Newest Member: omjtest
  • Most ever online: 396
    Guests: 396, Members: 0 on 12 Jan : 12:51
Members Birthdays:
All today's birthdays', congrats!
Dax (42)
Mino (49)


Next birthdays
11/29 Sonic (58)
11/29 kamelryttarn (46)
11/30 arnsfelt (45)
Contact
If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.


Special Thanks To:
  • Aaron Holmes
  • Aaron Wheeler
  • Adam Horden
  • Alan Scrimgeour
  • Andre
  • Andrew Haynes
  • Anonymous000
  • asabase
  • Austin Weil
  • barney
  • Barry
  • Bert Hickman
  • Bill Kukowski
  • Blitzorn
  • Brandon Paradelas
  • Bruce Bowling
  • BubeeMike
  • Byong Park
  • Cesiumsponge
  • Chris F.
  • Chris Hooper
  • Corey Worthington
  • Derek Woodroffe
  • Dalus
  • Dan Strother
  • Daniel Davis
  • Daniel Uhrenholt
  • datasheetarchive
  • Dave Billington
  • Dave Marshall
  • David F.
  • Dennis Rogers
  • drelectrix
  • Dr. John Gudenas
  • Dr. Spark
  • E.TexasTesla
  • eastvoltresearch
  • Eirik Taylor
  • Erik Dyakov
  • Erlend^SE
  • Finn Hammer
  • Firebug24k
  • GalliumMan
  • Gary Peterson
  • George Slade
  • GhostNull
  • Gordon Mcknight
  • Graham Armitage
  • Grant
  • GreySoul
  • Henry H
  • IamSmooth
  • In memory of Leo Powning
  • Jacob Cash
  • James Howells
  • James Pawson
  • Jeff Greenfield
  • Jeff Thomas
  • Jesse Frost
  • Jim Mitchell
  • jlr134
  • Joe Mastroianni
  • John Forcina
  • John Oberg
  • John Willcutt
  • Jon Newcomb
  • klugesmith
  • Leslie Wright
  • Lutz Hoffman
  • Mads Barnkob
  • Martin King
  • Mats Karlsson
  • Matt Gibson
  • Matthew Guidry
  • mbd
  • Michael D'Angelo
  • Mikkel
  • mileswaldron
  • mister_rf
  • Neil Foster
  • Nick de Smith
  • Nick Soroka
  • nicklenorp
  • Nik
  • Norman Stanley
  • Patrick Coleman
  • Paul Brodie
  • Paul Jordan
  • Paul Montgomery
  • Ped
  • Peter Krogen
  • Peter Terren
  • PhilGood
  • Richard Feldman
  • Robert Bush
  • Royce Bailey
  • Scott Fusare
  • Scott Newman
  • smiffy
  • Stella
  • Steven Busic
  • Steve Conner
  • Steve Jones
  • Steve Ward
  • Sulaiman
  • Thomas Coyle
  • Thomas A. Wallace
  • Thomas W
  • Timo
  • Torch
  • Ulf Jonsson
  • vasil
  • Vaxian
  • vladi mazzilli
  • wastehl
  • Weston
  • William Kim
  • William N.
  • William Stehl
  • Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Forums
4hv.org :: Forums :: General Science and Electronics
« Previous topic | Next topic »   

Effects of water networks

1 2 3 
Move Thread LAN_403
Ben Solon
Sat Jun 23 2012, 02:33PM Print
Ben Solon Registered Member #3900 Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
I am going to use water cooling for my induction heater. The problem is that this is a multi kW ih, and there are more parts than just the work coil that I want to cool. When I feed the water through both the grounded water block for the igbts and the work coil and maybe a few other components, I see a problem coming up. Has anyone done this and found that then causes live water or shorts? Water is fairly resistive, especially when fed though tubing like this, but I have also read somewhere that it tends to be more capacitive than anything else. Help?
Back to top
Nik
Sat Jun 23 2012, 02:57PM
Nik Registered Member #53 Joined: Thu Feb 09 2006, 04:31AM
Location: Ontario, Canada
Posts: 638
It would lower the heat transfer but you might try coating the inside of your waterblocks with something insulating (like the insulating pads you can put between a heatsink and a live part).
Back to top
Ash Small
Sat Jun 23 2012, 04:15PM
Ash Small Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
Don't take my word for it, but unless you have a lot of impurities in the water I imagine it won't be a problem.

Electricity takes the path of least resistance, so will tend to flow through your conductors (the metal parts) rather than the water.

As an example, consider a high resistance 'bleed resistor' accross a capacitor. It has very little effect on the circuit during normal operation.

Back to top
Ben Solon
Sat Jun 23 2012, 04:17PM
Ben Solon Registered Member #3900 Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
I'll try that if nothing else works, but that seems like it would dramatically reduce the effectiveness of water cooling. As long as there isn't more than a couple mA flowing through the water, I don't really care about voltage- I can just ground the hell out of everything. I know that the most basic water cooling uses the capacitor terminals as the input and output for water flow, so if it was a HUGE problem, then people would be shorting a couple amps through their water supply, but I just don't know enough about how it behaves.
Back to top
Alex M
Sat Jun 23 2012, 05:24PM
Alex M Registered Member #3943 Joined: Sun Jun 12 2011, 05:24PM
Location: The Shire, UK
Posts: 552
How about some of that liquid that is used in liquid cooled computers? That is made just for this purpose.

Another thing is if you are in a hard water area like me then regular tap water will cause lime-scale to appear, a bit of a pain when you have to replace the kettle every few months lol.

But yes the stuff they use for computer water cooling is what I would suggest.
Back to top
Steve Conner
Sat Jun 23 2012, 05:39PM
Steve Conner Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
It won't pass enough current to blow anything up. If there is a net DC component, you'll get electrolytic corrosion that will plug your cooling pipes with gunge after a while. But if the current is purely AC that's not a problem.
Back to top
Ben Solon
Sat Jun 23 2012, 06:14PM
Ben Solon Registered Member #3900 Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
So the tank itself won't have any issues, it can't hold dc current if it tried. I don't know exactly how I will wire it yet, but piping water from any circuit to any other circuit will be fine as long as there is another path? I will try to keep any dc component out of the system, an I could put in a filter to trap any junk form the water electrolysis. I don't want to use coolant though, cause I need to pump a lot of fluid, and in the extreme cases I will just hook a hose up to it to eliminate the radiator. I dont mind putting some kind of substance in the piping to each component- most of it wil be rubber or plastic anyways. But inside each cooling junction there has to be minimal thermal resistance.
Back to top
radiotech
Sat Jun 23 2012, 09:28PM
radiotech Registered Member #2463 Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546
Is the cooling water closed loop or just drained to a sewer?
Back to top
Proud Mary
Sat Jun 23 2012, 10:08PM
Proud Mary Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Freshly distilled water has a pH of about 7, and a resistance around 18MΩ cm.

After a few hours exposure to the air, in an open system, the water takes on CO2, forming carbonic acid. The pH of the water will fall to ~5.75, and the resistance fall to ~1MΩ cm.

Where atmospheric CO2 is abundant, the pH may fall to as low as 4.5, with correspondingly reduced resistance.

Moral of the story: where the dielectric properties of cooling water are important, only use freshly distilled water in an air-free closed system.
Back to top
Ash Small
Sun Jun 24 2012, 12:33AM
Ash Small Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245
Putting in 'extra' piping between the heatsinks, for example, will greatly increase the 'already high' resistance, if you really want to minimize any effects.

Any 'DC component' will possibly, over a long period, lead to 'electrolytic corrosion', see here:

Link2

but you probably don't need to worry about these things. (I'm just posting this as 'additional information').
Back to top
1 2 3 

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob

Go to:

Powered by e107 Forum System
 
Legal Information
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.