Filling the Portable Tank
The preferred gas for pressure chamber use is welding grade nitrogen
(N2) which is an inert gas and does not react with the plant
sample.
This
has been the standard since the early 1960s. If you do not already have
nitrogen,
a large "Supply Tank" can normally be bought or rented from a welding
or gas supply store at minimal cost.
* IMPORTANT - if you have a Model 610 (with an
internal tank) - click here to use
different
instructions. This process is slightly different.
Filling the Portable Tank is easy but care must be taken while
trans-filling
high pressure nitrogen. You need the following 4 items in order
to
make
a successful fill of the Portable Tank.
1. Portable Tank
2. Supply Tank (Large filling tank)
3. 6 Foot Filling Hose
4. Supply Tank Adaptor

Supply Tank (left) - Portable Tank (right)
6 Foot Filling Hose - Supply Tank Adaptor (center)
Next, you will need to connect the two
tanks together using the Supply
Tank Adaptor and the 6-Foot Filling Hose.

Connect the CGA-580 fitting (screw end) of the 6-Foot Filling Hose into
the
Portable Tank
Tighten Hand Nut.

Screw the Supply Tank Adaptor into the Supply Tank
.

Connect Supply Tank Adaptor and 6-Foot Filling Hose
You will need to pull back on the coupler on the Supply Tank Adaptor
to get a proper connection
Pull gently on hose to ensure properly connected

The tanks should now look like this.



Ensure that the following valves are all shut before proceeding
Supply Tank Valve, Portable Tank Valve and the Pressure Relief Valve
Now you are ready to start filling

Start by opening up the Supply Tank Valve completely

This will allow gas to flow to the Portable Tank and pressure will
register
on the gauge

++++ IMPORTANT ++++
***** BARELY OPEN THE VALVE *****
JUST CRACK IT OPEN
Allow the nitrogen to slowly fill the Portable
Tank
You will hear the nitrogen as it fills the tank. You should take
about 1-2 minutes to fill the tank. As the pressure equalizes,
continue
to open up the valve a little bit more. Continue this process
until
the pressure has equalized completely. If you open the valve up
to
quickly and let too much gas into the tank - the valve will become
HEATED
and could have problems or fail. This is due to the gas
compressing
into
the empty tank.
When the pressure has equalized, seal the Portable Tank first, then
seal the Supply Tank. The Pressure Relief Valve will allow you to
let the
pressure escape from the hose. Now you can disconnect your hose
from
the Supply Tank Adaptor and connect it to your Pressure Chamber.
You
are now ready to take measurements.
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