Thermo Forma 3950, Руководство по эксплуатации и техническому обслуживанию

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i. Connecting the CO
2
Gas Supply
High concentrations of CO
2
gas can cause
asphyxiation.
OSHA Standards specify that employee exposure
to carbon dioxide in any 8-hour shift of a 40-
hour work week shall not exceed the 8-hour time
weighted average of 5000 PPM (0.5% CO
2
). The
short-term exposure limit for 15 minutes or less is
30,000 ppm (3% CO
2
). Carbon dioxide monitors
are recommended for confined areas where con-
centrations of carbon dioxide gas can accumu-
late.
This incubator is designed for CO
2
gas only.
Connecting a flammable or toxic gas could result
in a hazardous condition.
Gases other than CO
2
should not be connected to
this equipment. CO
2
gas cylinders have a UN1013
label on the cylinder and are equipped with a
CGA 320 outlet valve. Check the gas cylinder for
the proper identification labels. The CO
2
gas sup-
ply being connected to the incubator should be
industrial grade, 99.5% pure. Do not use CO
2
gas
cylinders equipped with siphon tubes. A siphon
tube is used to extract liquid CO
2
from the cylin-
der, which can damage the pressure regulator.
Consult with your gas supplier to ensure that the
CO
2
cylinder does not contain a siphon tube. Gas
cylinders should also be secured to a wall or
other stationary object to prevent them from tip-
ping.
A two-stage CO
2
pressure regulator is required to
be installed on the outlet valve of the gas cylinder.
Input pressure to the incubator must be main-
tained at 15 psig (103.4 kPa) for proper perform-
ance of the CO
2
control system. A single stage
CO
2
pressure regulator will not maintain 15 psig
(103.4 kPa) to the incubator as the pressure in
the CO
2
cylinder decreases; therefore, a two-stage
regulator is recommended.
If higher purity CO
2
is desired inside the incuba-
tor (greater than 99.5% pure), the pressure regu-
lator should be constructed with a stainless steel
diaphragm, along with specifying the purity of the
CO
2
from the gas supplier. Follow the manufac-
turer’s instructions to ensure proper and safe
installation of the pressure regulator on the gas
cylinder.
Consult your facility safety officer to ensure that
the equipment is installed in accordance with the
codes and regulations that are applicable in your
area.
The CO
2
gas supply being connected should be industrial
grade 99.5% pure and should not contain siphon tubes. Install a
two-stage pressure regulator at the cylinder outlet. The high
pressure gauge at the tank should have 0-2000 psig range. The
low pressure gauge, at the incubator inlet, should have a 0-30
psig range. Input pressure to the incubator must be maintained
at 15 psig (103.4 kPa).
Each tank should be connected to one incubator
only.
The incubator has serrated fittings on the back of the cabi-
net to connect the gas supply. Refer to Figure 1-2. The fitting is
labeled CO
2
Inlet #1 Tank. Make sure that the connections are
secured with clamps. Check all fittings for leaks.
For units having the CO
2
Gas Guard option, refer to
Section 6.2.
1.4 Incubator Start-Up
With the incubator properly installed, connected to power,
the humidity reservoir filled and the unit connected to a gas
supply, system setpoints can be entered. The following set-
points can be entered in Set Mode: Temperature,
Overtemperature and CO
2
. To enter Set Mode, press the Mode
key until the Set indicator lights. Press the right and/or left
arrow keys until the proper parameter appears in the message
display center. See Chart 1-1 for more detail.
a. Setting the Operating Temperature
This incubator has an operating temperature range of
10.0°C to 60.0°C, depending on ambient temperature. It is
shipped from the factory with a temperature setpoint of 10.0°
C. At this setting, all heaters are turned off. To change the
operating temperature setpoint:
1. Press the Mode key until the Set indicator lights.
2. Press the right arrow until “Temp XX.X” is displayed in
the message center.
3. Press up/down until the desired temperature setpoint is
displayed.
4. Press Enter to save the setpoint.
5. Press the Mode key until the Run indicator lights for
Run mode or press the right/left arrow keys to go to
next/previous parameter.
Any equipment placed inside chamber must be
rated for unit operating temperature and humidity.
Model 3950/3951 ____________________________________________________________________Installation and Start-Up
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