NEW BRUNSWICK SCIENTIFIC CO28IR, Руководство по эксплуатации

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19
New Brunswick Scientific User’s Manual
The CO
2
inlet fittings are located at the back of the unit near the top ( see Figure 6 ).
They are marked
CO
2
TO CHAMBER
.
You have the option of using one or two tanks. A supply hose with in-line CO
2
f
ilter
(supplied) connects from each fitting to a CO
2
tank and regulator.
If you plan to use only one tank, it does not matter which fitting you connect the
supply hose to. We recommend, if you are not using the second fitting, that you
cover it with the black vinyl cap provided, to prevent the entry of dust or dirt.
If you plan to use two tanks, set the output pressure of one tank to 15 psi and the
other tank to 20 psi. The internal tank switch (
“shuttle valve” in Figure 6 ) will use
up the 20 psi first and then switch over to the 15 psi tank. It does not matter which
tank is attached to which fitting. When the 20 psi tank is empty, its pressure gauge
will indicate 15 psi. At this time, the empty tank can be replaced.
Be sure to use a good quality 0-60 psi output range dual stage pressure regulator on
the CO
2
tank(s). The dual stage regulator will have two pressure gauges. The high
pressure gauge (0-4000 psi) will indicate the pressure within the tank. The low
pressure gauge (0-60 psi) will indicate the output pressure on the supply hose to the
incubator.
Do not use single stage regulators : they will not supply a stable pressure.
Verify that you are using a dual stage regulator; the presence of two gauges on a
regulator is not a guarantee that the regulator is dual stage.
It is normal for the high pressure gauge on your regulator to start out reading 800 to
1000 psi with a full tank. The reading will drop to 500 to 800 psi quickly and will stay
there for most of the time the tank contains CO
2
. At the end of use, the pressure will
drop quickly to zero to indicate that the tank is completely empty. Because pure CO
2
is in a liquid state in the tank, a constant vapor pressure is generated in the tank above
the liquid level. The CO
2
is drawn off the top as a gas. The same vapor pressure is
maintained as long as any liquid is left in the tank; when the last of the liquid has
evaporated into gas, the pressure will drop rapidly as the remaining gas is drawn off.
Only medical grade CO
2
should be used in your incubator. The use of any lower
quality CO
2
may damage your incubator and void your warranty.
CAUTION
!
Always use a dual stage pressure regulator on the CO
2
tank(s).
CAUTION
!
Use only medical grade CO
2
in your incubator.