Thermo Forma 3950, Руководство по эксплуатации и техническому обслуживанию

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To access the analog board:
1. Turn off the incubator and unplug it from the power out-
let.
2. Remove the top of the incubator.
3. Locate the Analog Output board.
4. Strip the ends of the conductor and wire it to the appro-
priate terminals of connectors J2 on the analog board.
Refer to Figure 6-4.
5. Route the wires through the auxiliary hole located on the
back of the unit. See Figure 6-3 and Figure 6-5.
6. When wiring is completed, replace the unit top and
return the unit to service.
6.2 CO
2
Gas Guard (1900000)
CO
2
can be lethal in high concentrations. Refer to
the warnings in Section 1.4.i of this manual.
The 3950 Series incubators can be equipped with a built-in
Gas Guard system that will operate with a CO
2
gas supply. The
Gas Guard uses two pressure switches to continuously monitor
the pressures of two independent CO
2
supplies and automatical-
ly switches from one supply to the other when the supply pres-
sure drops below 10 psig (0. 690 bar). Do not use the Gas
Guard with multiple incubators.
The CO
2
gas supplies must be equipped with two-stage
pressure regulators with gauges. The high pressure gauge at the
tank should have a 0-2000 psig range and the low pressure
gauge should have a 0-30 psig range. The gas supply to the
incubator must be maintained at 15 psig (1.034 bar). Gas pres-
sures below 15 psig will cause nuisance alarms to occur on
incubators equipped with the built-in Gas Guard.
a. Connecting the CO
2
Gas Supplies
The CO
2
inlets for the Gas Guard are located on the rear of
the unit. Using 1/4” ID tubing, connect one of the CO
2
supply
tanks to the fitting labeled CO
2
Inlet #1 Tank. Connect the sec-
ond CO
2
supply tank to the fitting labeled CO
2
Inlet #2 Tank.
Install 3/8” hose clamps to secure the 1/4” ID tubing to the fit-
tings. (Refer to Figure 6-6.)
b. Activating the Gas Guard
The built-in Gas Guard is not turned on when shipped from
the factory. The tank selected (Tank Sel) has been specified as
Tank 1. Refer to Section 3 Configuration, to activate the Gas
Guard or change the Tank Sel from #1 to #2. If the Gas Guard
system is not used, the incubator will function normally by sup-
plying CO
2
from the supply tank connected to Inlet #1.
c. Operation of the CO
2
Gas Guard
With the Gas Guard in operation, the incubator will use the
gas supplied by the tank connected to Inlet #1 until the pressure
drops below 10 psig (0.690 bars). At this time, the Gas Guard
automatically switches to the gas supplied through CO
2
Inlet
#2.
In addition, the incubator automatically changes the Tank
Sel in Configuration Mode from 1 to 2 to indicate that the incu-
bator is now using gas supplied through Inlet # 2. If the gas
supply to Inlet #1 is replenished, the incubator will continue to
operate using the gas supplied through Inlet #2 unless the oper-
ator changes the Tank Sel from #2 to #1 through Configuration
Mode. Refer to Section 3, Configuration.
Model 3950/3951 __________________________________________________________________________Factory Options
6 - 2
TE
M
P
J3
J2
TE
M
P
CO
2
CO
2
RH CO
M
+ -
+
-
+ -
For ma Sc i en t
Fuse 1 amp ( .5 amp 3951)
Fuse 2.5 amp (1.5 amp 3951)
Analog Board
CO
Filter
2
RS 485 Connection
Alarm Contacts
Blower Motor
CO Sensor
2
CO
Valve
2
Micro Board
Power Supply
Figure 6-4
Figure 6-5
RS 485
ALARM CONTACTS
30V MAX / 1A MAX
#2
Co Inject
15 p.s.i. Regulated
(103.4 kPa)
2
#1
CO Inject
15 p.s.i. Regulated
(103.4 kPa)
2
AUXILIARY HOLE
FOR CABLES
Figure 6-6