[Amps] Can distilled water be used for a dummy load ??

[Dr. David Kirkby]

On 11/29/11 02:05 PM, Jim Thomson wrote:
> My  hb 50 ohm dummy load  consists of  4 x 200 ohm globars in parallel  [type SP, glass bodied
> and suitable for oil immersion].   Each resistor is 1" diam x 12"  long. [275 W CCS in air]
>   Each resistor  resides inside it's own  2.875" OD x sched 40  Aluminum tube.
>   All 4 x thick walled  AL tubes are heliarc welded.
>
> I heard some place that instead of xfmr oil, that  distilled water can be used instead?
> The same glass bodied type SP  resistors, [50 ohm, high wattage]  are used in  water cooled loads,
> the type that  has the garden hose on one end, etc.

IIRC the dielectric constant of water is about 80, so it is very high compared 
to most other materials, so there is certainly the potential to increase 
capacitances quite a bit, but depending on the sizes and spacing of conductors, 
as well as frequency, that might not be an issue.

I'd certainly add corrosion inhibitor. The inhibitors for central heating 
systems might be a good choice, as you don't need a lot of them, so I don't 
think it would significantly reduce the specific heat capacity of the liquid.

Never tried it. I'd personally be a bit reluctant, but I can conceded there are 
cost savings and spillage is less of an issue. My Bird load has a silicon oil, 
but that stuff is expensive.

Dave