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Patch
12th February 2006, 08:54
Any of you smart electrical chaps know how to measure the electrical resistance of water. I need to have it reach 0.3 ohms.

Your thoughts and ideas would be greatly appreciated.

Cheers

idb
12th February 2006, 09:10
Any of you smart electrical chaps know how to measure the electrical resistance of water. I need to have it reach 0.3 ohms.

Your thoughts and ideas would be greatly appreciated.

Cheers
I'd suggest that a 500 volt tester would be best (usually know as a Megger). Any electrician should have access to one.
Suspend the test leads in the water at opposite ends of the container and test away.
If my memory of high school science is correct, adding salt should lower the resistance of the water.

Patch
12th February 2006, 09:21
I have a Caltek Digital Multimeter, set it on the lowest ohm setting, dropped the leads each side of the container, added baking soda but the reading didn't change.

Any idea as to how much soda or salt to use? and do I have the meter set right? :wacko:

jonbuoy
12th February 2006, 09:30
I don't think you'll get it to read 0.3 ohms. A few Kohms if you chuck lots of salt into some hot water - 0.3s pretty low - depends on how close your leads are too.

idb
12th February 2006, 09:36
I have a Caltek Digital Multimeter, set it on the lowest ohm setting, dropped the leads each side of the container, added baking soda but the reading didn't change.

Any idea as to how much soda or salt to use? and do I have the meter set right? :wacko:
I don't think a multimeter will do it, it only operates at a few volts.
You need more power!
As for if you can actually reach 0.3 ohms in water or not, I can't say.

FlyingDutchMan
12th February 2006, 11:02
Any of you smart electrical chaps know how to measure the electrical resistance of water. I need to have it reach 0.3 ohms.

Your thoughts and ideas would be greatly appreciated.

Cheers

I think that 0.3 Ohms would be near impossible. But to maximise your chances of getting a reading like that, use two large metal sheets very close together in the water. Then throw in salt/battery acid/copper sulphate, etc. Be careful with the chemical concotion tho.