Conductivity ammonia

[virk]

Hello!

Who of you knows the conductivity of liquid ammonia (mS/cm)? I don't find anything on the web...It's (I am) unbelievable.

I need it for the decision whether a certain level switch can be used.

Kind regards

 

[hacksaw]

the anhydrous form is a dielectric

 

[smckennz]

Sensitivity to Static Charge:
Liquefied ammonia will not accumulate static charge, since the electrical conductivity is high.



Electrical Conductivity:
1.3 X 10(7) pS/m (- 79 deg C ) (32); 3 X 10(9) pS/m (commercial) (-35 deg C) (31)



Minimum Ignition Energy:
680 millijoules (32)

The googled info above is from

http://www.intox.org/databank/documents/chemical/ammonia/cie48.htm

I am not familiar with the firm however so you will need confirmation, and probably a few more data points.



Cheers

Steve

 

[hacksaw]

in Langes hand book the resistivity of anhydrous ammonia at -79 oC is 1.3(10-7) ohm-1/cm (this aggres with above).

Its dielectric constant is 22.4.


if I have my unit conversions correct,

at -79 oC the resistivity is 0.76 (10^7) ohm-cm
at -36 oC the resistivity is 0.33(10^5) ohm-cm

this is a pretty high resistivity. as soon as it picks up water, it will plumet.

 

[nbucska]

VIRK:
30+yrs in engineering convinced me that not every problem
deserves a solution -- often it is better to design around
it.

I would use permanent magnet activated Reed-switch,
e.g. in the middle of a long heatshrink tube.( The magnet
would be mounted on a float)



<nbucska@pcperipherals.com>

 

[hacksaw]

no disagreement about advice regarding avoidance of certain instrument types in this service, but that is not the question

 

[nbucska]

Not every question deserves answer, either...

<nbucska@pcperipherals.com>

 

[hacksaw]

agreed, truer words have not been spoken...

 

[virk]

Thank you all.

The measuring method (conductivity) does not seem to be suitable. We haven chosen for liquiphant (stem fork) method.

Kind regards

Virk