Thermo Scientific 3920 User manual

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User Manual
Forma Environmental Chamber
Model 3920
Operating and Maintenance Manual 7063920 ev. 12

Thermo Scientific
MANUAL NUMBE 7063920
12 40398 4/20/17 Updated 3920 electrical schematics bpg
11 40639 5/9/16 Added risk assessment information ccs
10 40356/40509/ 3/18/16 Updates to fuses, accessory outlet, electrical schematics ccs
40638/IN-4670
9 40638 1/26/16 Added wall anchor information to pg 1-2 ccs
8 40018 2/10/15 Added drain figure to pg 1-3 ccs
7 28882/IN-4244 9/24/14 Updated drains in assembly drawing 3920-00 ccs
-- 31358/IN-4569 7/24/14 Door light option part number is now 1900604 ccs
6 30415 10/14/13 Added instructions for left hand door access to control panel and recorder install ccs
Preface
Environmental Chamber i

Thermo Scientificii Environmental Chamber
Preface
Contains Parts and Assemblies
Susceptible to Damage by
Electrostatic Discharge (ESD)
CAUTION
Important Read this instruction manual. Failure to read, understand and follow the instructions in this manual
may result in damage to the unit, injury to operating personnel, and poor equipment performance. s
Warning All internal adjustments and maintenance must be performed by qualified service personnel. s
• Use this product only in the way described in the product literature and in this manual. Before
using it, verify that this product is suitable for the intended use.
• Do not modify system components, especially the controller. Use O M exact replacement
equipment or parts. Before use, confirm that the product has not been altered in any way.
• Disconnect the unit from all power sources before cleaning, troubleshooting, or performing
other maintenance on the product or its controls. To disconnect power supply to the incubator,
unplug the supply cord at the back of the incubator. Note that turning the key switch on the
front control panel to the Off position is not sufficient to disconnect power.
Warning The user is responsible for carrying out appropriate decontamination procedures when hazardous
materials are spilled on or inside the incubator. s
Caution If the incubator is not used in the manner specified in this operating manual, the protection provided
by the equipment design may be impaired. s
Material in this manual is for information purposes only. The contents and the product it describes are subject
to change without notice. Thermo Fisher Scientific makes no representations or warranties with respect to this
manual. In no event shall Thermo be held liable for any damages, direct or incidental, arising out of or related
to the use of this manual.
©2011 Thermo Fisher Scientific. All rights reserved.

Thermo Scientific Environmental Chamber iii
Preface
Important operating and/or maintenance instructions. Read the accompanying text carefully.
Potential electrical hazards. Only qualified persons should perform procedures associated with this
symbol.
quipment being maintained or serviced must be turned off and locked off to prevent possible injury.
Asphyxiation Hazard Warning. High concentrations of CO2 and N2 can displace oxygen and cause
asphyxiation!
Lifting Hazard Warning. The incubator weighs more than 200lbs (91kgs). Take adequate safety
measures when moving this device.
W Compliance: Thermo Fisher Scientific has contracted with companies for recycling/disposal in
each U Member State. For further information, send an email to [email protected].
4Always use the proper protective equipment (clothing, gloves, goggles, etc.)
4Always dissipate extreme cold or heat and wear protective clothing.
4Always follow good hygiene practices.
4ach individual is responsible for his or her own safety.

Thermo Scientificiv Environmental Chamber
Preface
Do You Need Information or Assistance on
Thermo Scientific Products?
If you do, please contact us 8:00 a.m. to 6:00 p.m. (Eastern Time) at:
1-740-373-4763 Direct
1-800-438-4851 Toll Free, U.S. and Canada
1-877-213-8051 FAX
http://www.thermofisher.com Internet Worldwide Web Home Page
[e-mail] Tech Support Email Address
Certified Service Web Pagewww.unitylabservices.com
Our staff can provide information on pricing and give you quotations. We canSales Support
take your order and provide delivery information on major equipment items or make
arrangements to have your local sales representative contact you. Our products are listed on the
Internet and we can be contacted through our Internet home page.
Our staff can supply technical information about proper setup, operation orService Support
troubleshooting of your equipment. We can fill your needs for spare or replacement parts or
provide you with on-site service. We can also provide you with a quotation on our Extended
Warranty for your Thermo Scientific products.
Whatever Thermo Scientific products you need or use, we will be happy to discuss your
applications. If you are experiencing technical problems, working together, we will help you
locate the problem and, chances are, correct it yourself...over the telephone without a service
call.
When more extensive service is necessary, we will assist you with direct factory trained
technicians or a qualified service organization for on-the-spot repair. If your service need is
covered by the warranty, we will arrange for the unit to be repaired at our expense and to your
satisfaction.
Regardless of your needs, our professional telephone technicians are available to assist you
Monday through Friday from 8:00 a.m. to 6:00 p.m. Eastern Time. Please contact us by
telephone or fax. If you wish to write, our mailing address is:
Thermo Fisher Scientific (Asheville) LLC
401 Millcreek Road, Box 649
Marietta, OH 45750
International customers, please contact your local Thermo Scientific distributor.

Thermo Scientific Environmental Chamber v
Preface
Warranty Notes
Information You Should Know Before Requesting Warranty Service
•Locate the model and serial numbers. A serial tag is located on the unit itself.
• For equipment service or maintenance, or with technical or special application inquiries, contact Technical
Services at 1-800-438-4851 or 1-740-373-4763 (USA and Canada). Outside the USA, contact your local
distributor.
Repairs NOT Covered Under Warranty
• Calibration of control parameters. Nominal calibrations are performed at the factory; typically ±1°C for
temperature, ±1% for gases, and ±5% for humidity. Our service personnel can provide precise calibrations as
a billable service at your location. Calibration after a warranty repair is covered under the warranty.
• Damage resulting from use of improper quality water, chemicals or cleaning agents detrimental to
equipment materials.
• Service calls for improper installation or operating instructions. Corrections to any of the following
are billable services:
1) electrical service connection
2) tubing connections
3) gas regulators
4) gas tanks
5) unit leveling
6) room ventilation
7) adverse ambient temperature fluctuations
8) any repair external to the unit
• Damage resulting from accident, alteration, misuse, abuse, fire, flood, acts of God, or improper
installation.
• Repairs to parts or systems resulting from unauthorized unit modifications.
• Any labor costs other than that specified during the parts and labor warranty period, which may
include additional warranty on CO2sensors, blower motors, water jackets, etc.

Environmental Chamber viThermo Scientific
Table of Contents
Installation and Set-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Preliminary Cleaning and Disinfecting . . . . . . . . . . . . . . . . . . . . . . .1-2
Installing the Shelves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Installing the Wall Anchors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Attaching the Drain Connections . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Leveling the Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
4-20 Milliamp Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Remote Alarm Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Power Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Set Overtemp Safety Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Set Overtemp Safety Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Set Undertemp Safety Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Prepare (Optional) CoBex Recorder . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Change Chart Paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Change Pen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Honeywell Recorder (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Access Control Panel w/ Left Hand Door Swing . . . . . . . . . . . . . . . .1-7
IR CO2Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
Connect CO2Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
Set CO2Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
CO2Control and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
Accessory Outlet (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9
Door Light (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9
Start-Up and Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Set the Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Air xchange Ventilator Caps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
outine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Section 1
Section 2
Section 3

vii Environmental Chamber Thermo Scientific
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
lectrical Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Repl. Over/ Undertemp Probe & Thermostat . . . . . . . . . . . . . . . . . .4-1
Replace Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Program Temperature Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Remove Software Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Restore Software Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Controller Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Offset Calibration (Temperature) . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Replace Optional Recorder and Probe(s) . . . . . . . . . . . . . . . . . . . . . .4-5
Set the Door Heater Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
CO2Controller Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1
efrigeration Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1
Electrical Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-1
Wiring Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-7
Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
Table of Contents
Section 4
Section 5
Section 6
Section 8
Section 7
Section 9

Environmental Chamber 1-1Thermo Scientific
Section 1 Installation and Set-Up
Figure 1-1. Front View Figure 1-2. Side View
Locate the unit on a firm, level surface in an area of minimum ambient
temperature fluctuation. A minimum of six (6) inches clearance is required
at the top and back of the incubator, plus a minimum three (3) inch
clearance on each side. This space is necessary to allow adequate air flow
around the refrigeration system. At least eight (8) inches of clearance is
required at the top of the incubator for service access.
Location

610105
5/16-18 UNC
STAINLESS STEEL
RIVNUT
3176856
5/16-18 x 1”
HH FULL THREAD
SS CAP SCREW
23036
5/16 INT. TOOTH
LOCKWASHER
Figure 1-3. Wall Anchor Installation
Warning To prevent
tipping, install the wall
anchors and secure the
unit before using. s
1-2 Environmental Chamber Thermo Scientific
Section 1
Installation and Set-Up
Disinfect all interior surfaces with a general-use laboratory disinfectant,
such as quaternary ammonium, to remove any residues which may remain
from production of the incubator. Rinse thoroughly with sterile distilled
water, then 70% ethanol. Dry with a sterile cloth as needed.
Caution Before using any cleaning or decontamination method except
those recommended by the manufacturer, users should check with the
manufacturer that proposed method will not damage the equipment. s
The shelves may be installed at any level in the incubator. Install a shelf
channel on each side. With the tabs pointing up, attach the channel by
locating the rivet into a slotted hole, far end first. Pull the channel toward
the front and slide the front rivet on the channel into the slotted hole and
press down. Make sure that the channels are opposite each other so that
the installed shelf will be level.
Preliminary Cleaning
and Disinfecting
Installing the Shelves
Installing the Wall
Anchors
The unit has two wall anchor studs located in the left and right side of
the cabinet. Use the provided 5/16” bolts to secure the wall anchors to
each side of the cabinet top. Anchors that connect between the cabinet
sides to facility wall are customer supplied.
Note Wall anchors are required to meet UL Tip Test Safety Standards.
Figure 1-4. Shelf Channels

Environmental Chamber 1-3
Thermo Scientific
Section 1
Installation and Set-Up
Place a bubble-type level on a shelf inside the incubator. Adjust the feet as
needed; counterclockwise to lengthen or clockwise to shorten. Level the
unit front-to-back and left-to-right.
The cabinet’s 3/8” MPT drain line connection is located on the rear
(lower left side) of the cabinet (Figure 1-5). A P-trap is included with the
unit and must be installed on the connection.
To install the drain connection:
1. Using Teflon pipe thread tape, tape the threads on the cabinet drain
connection.
2. Using an open end adjustable wrench, install the P-trap onto the
connection. Make sure the trap section is positioned down.
3. Push a piece of 3/8” ID tubing onto the trap and direct the tubing to a
convenient drain. Install a hose clamp on the tubing, if desired. A
condensate evaporator (P/N 1900031) or condensate pump (P/N
184062) may also be used.
To connect the nylon adapter from the front drip trough, do not install a
p-trap. Push a piece of 3/8” ID tubing onto the nylon adapter and direct
the tubing to a convenient drain. Install a hose clamp on the tubing, if
desired.
The environmental chamber is equipped with 4-20mA output for the
remote transmission of temperature or CO2data. A terminal strip is
located on the back of the incubator for convenience. See Figure 1-6 for
terminal pin identification.
Attaching the Drain
Connections
Leveling the Unit
Nylon adapter for
front drip trough. DO NOT TRAP.
Drain connection for evaporator
and floor drain. Requires a P-TRAP.
Figure 1-5. P-trap Installation Location
4-20 Milliamp Output
Figure 1-6. Terminal Strip Connections

Remote alarm connections are also included on the terminal strip (Figure
1-6) providing Normally Open (N.O.) and Normally Closed (N.C.)
contacts. C is the Common terminal. The remote alarm will activate when
either the incubator’s temperature or CO2go out of the set alarm limits.
See the serial tag on the side of the unit or the Specifications section in this
manual for electrical specifications. Refer to the electrical schematics at the
end of this manual.
Caution Connect the incubator to a grounded, dedicated circuit. The
power cord connector is the mains disconnect device for the incubator.
Position the incubator to allow unobstructed access to the power cord so it
can be easily disconnected in an emergency. s
Plug the provided 8 ft. power cord with a N MA 5-20 plug into the
grounded dedicated electrical circuit. A N MA 5-30 plug is provided on
units with the optional door light package.
Preset the controls as follows:
Overtemp Safety Thermostat . . . . . . Fully clockwise
Undertemp Safety . . Thermostat fully counterclockwise
Main Power Switch . . . . . . . . . . . . . . . . . . . . . . .ON
Temperature Controller . . . . . . . . . .Desired setpoint
Door Heater . . . . . . . . . . . . . . . . . .40% (factory set)
Turn the Main Power switch on. The Power indicator and Heat indicator
(if temp setpoint is above ambient temp) will light. Turn the Refrigeration
switch on and the indicator will light.
Allow the chamber temperature to stabilize, then set the overtemp safety
thermostat as follows:
1. Turn the overtemp control knob slowly counterclockwise until the
audible alarm sounds and the overtemp indicator lights.
2. Turn the overtemp control knob clockwise at least 2 degrees. The
alarm should be silenced and the overtemp indicator light should go
out. The overtemp safety thermostat is now set a few degrees above the
control temperature setpoint. When the chamber temperature rises to
the overtemp control point, the alarm system will activate, power to
the heaters will shut off, and the chamber temperature will be
maintained at the overtemp control point.
When an overtemp condition occurs, the cause must be determined and
corrected before normal operation under the main temperature controller
can be resumed.
1-4 Environmental Chamber Thermo Scientific
Start-Up
Section 1
Installation and Set-Up
Set Overtemp Safety
Thermostat
Power Connection
emote Alarm
Contacts

Note When the chamber temperature control setpoint is changed, the
overtemp safety thermostat must be reset to accommodate the change. s
Note The overtemp control is not directly calibrated. The numbers on the
dial are for reference only. s
Allow the chamber temperature to stabilize, then set the undertemp safety
thermostat as follows:
1. Turn the undertemp control knob slowly clockwise until the audible
alarm sounds and the undertemp indicator lights.
2. Turn the undertemp control knob counterclockwise at least 2 degrees
on the scale. The alarm should be silenced and the undertemp
indicator light should go out.
The undertemp safety thermostat is now set a few degrees below the
control temperature setpoint. When the chamber temperature drops to the
undertemp control point, the alarm system will activate, power to the
compressor will shut off, and the chamber temperature will be maintained
at the undertemp control point.
When an undertemp condition occurs, the cause must be determined and
corrected before normal operation under the main temperature controller
can be resumed.
Note When the chamber temperature control setpoint is changed, the
undertemp safety thermostat must be reset to accommodate the change. s
Note The undertemp control is not directly calibrated. The numbers on
the dial are for reference only. s
The seven-day circular
chart recorder is located on
the front of the incubator
cabinet and is protected by
a glass door.
To prepare the recorder for
operation, open the glass
door and snap the
connector onto the 9-volt
battery (Figure 1-8).
Environmental Chamber 1-5Thermo Scientific
Set Overtemp Safety
Thermostat (cont.)
Set Undertemp Safety
Thermostat
Section 1
Installation and Set-Up
Prepare (Optional)
CoBex ecorder
12
3
time line
groove
press to
change
chart
slotted screws
(loosen only)
9-volt battery
Figure 1-8. ecorder Components

If the unit is operating, the green L D lights steady. If the unit is not
turned on, the L D blinks.
If the battery is weak or not connected, the green L D will flash. If power
is lost to the cabinet, the L D will also flash. When replacing the 9-volt
battery, use only an alkaline style battery. Dispose of the old battery
following established environmental practices.
1. Press the #3 Change Chart button (Figure 1-8) and hold it for 1
second until the pen begins to move to the left of the chart.
2. Remove the existing chart by unscrewing the center knob securing it.
3. Install the new chart, positioning it so that the correct time line
coincides with the time line groove on the chart plate.
4. Replace the center knob and screw it tightly against the chart.
1. Using a small flat blade screwdriver, loosen the 2 screws holding the
pen arm and remove the pen and arm as an assembly.
2. Unsnap the plastic hinge securing the pen. Remove and discard the old
pen.
3. Install the new pen by snapping the hinge securely around the pen
arm.
4. Re-install the pen assembly by sliding the pen arm under the screws,
positioning the pen tip in the time line groove. Tighten the screws.
5. Push the Chart Change button and hold it for 1 second until the pen
begins to move back onto the chart.
Note Make sure that the pen is marking on the chart. It may be necessary
to gently lift the pen onto the chart paper. s
The Honeywell, DR 4500 Recorder is a one to four-channel
microprocessor-based, circular chart recorder.
The recorder is capable of recording both temperature and humidity and
printing alphanumeric chart data on blank heat-sensitive chart. Refer to
the Honeywell Configuration Record at the end of Section 4 and the
supplemental Honeywell Recorder manual.
1-6 Environmental Chamber Thermo Scientific
Change Chart Paper
Section 1
Installation and Set-Up
Change Pen
Honeywell ecorder
(Optional)
Set (Optional) CoBex
ecorder (cont.)

1. After disconnecting the unit from power, remove the two screws from
the top and the two screws on the bottom, of the control panel. Retain
them for re-assembly.
2. Pull gently on the right side of the control panel to disengage it from
the tabs. You may need to lift slightly to swing open the panel.
3. Install the recorder to the top of the unit, over the studs. Use the
supplied nuts to secure tightly in place.
4. Locate the white connector in the top housing of the unit. Connect it
to the plug in the base of the recorder.
5. Close and latch the control panel door.
1. After disconnecting the unit from power, disconnect the door plug
from the lower left corner of the control panle. Allow it to hang, still
connected to the door.
2. Remove the two screws from the top and the two screws on the
bottom, of the control panel. Retain them for re-assembly.
2. Pull gently on the right side of the control panel to disengage it from
the tabs. You may need to lift slightly to swing open the panel.
This section applies to units with the IR CO2option only.
For the most economical use, the liquid CO2supply tanks should be
without siphon tubes, so that only CO2gas enters the incubator injection
system. Two tanks may be joined together with a manifold to ensure a
continuous CO2supply.
Note For customer convenience, 12 feet of 1/4" I.D. vinyl tubing with
two 3/8" hose clamps are included in the shipping materials for
connecting the unit to the gas supply.
The CO2source must be regulated at a pressure level of 15 psig, ±5.
Higher pressure levels may damage the CO2control system. The user
should determine the most economical pressure level, between 10 and 20
psig appropriate for the desired CO2percentage in the chamber. Use only
sufficient pressure to maintain recovery time after door openings.
Environmental Chamber 1-7Thermo Scientific
I CO2Option
Section 1
Installation and Set-Up
Connect CO2Source
Connect the ecorder
(continued)
Access Control Panel w/
Left Hand Door Swing

To connect the CO2supply:
1. Insert the copper tubing provided with
the unit as far as it will go into the nut
of the CO2 connection.
2. Turn the nut until it is finger tight.
3. For reference, scribe the nut at the 6:00
position.
4. While holding the fitting body steady with a wrench, tighten the nut
1-1/4 turns until the mark is at the 9:00 position.
5. Securely attach the CO2line to the open end of the copper tubing.
6. Check the tubing connection for leaks.
The Watlow PM6 CO2controller's upper display
shows the actual CO2content inside the
chamber. The lower display shows the CO2
setpoint.
Before setting the CO2Content, allow the
chamber temperature to stabilize. Do not open
door during the stabilization period.
To set the CO2content, press the Up or Down
Arrow keys on the Watlow PM6 Controller.
The sample port is used for checking CO2
percentage in the incubator chamber by an independent test instrument
(such as with a Fyrite, or similar CO2test instrument).
Caution To prevent CO2loss, the sample port must be capped when it is
not in use. s
The CO2alarm is factory set to activate when the chamber CO2content
deviates from configured alarm set points (see configuration record). When
a CO2alarm occurs, the CO2Alarm indicator on the control panel lights
and the audible alarm sounds.
The CO2alarm high and low setpoints are established through the Watlow
PM6 CO2controller (A.LO, and A.HI). Refer to the Configuration
Record included at the end of Section 4.
1-8 Environmental Chamber Thermo Scientific
Set CO2Content
Section 1
Installation and Set-Up
CO2Control and Indicators
sample port
POWER
CO
alarm
2
EZ
WATLOW EZ-ZONE
Figure 1-10. CO2Control and
Indicators
CO inlet2
Figure 1-9. CO2 Inlet
Connect CO2Source
(continued)

The door lighting package provides light to the incubator chamber. The
package consists of eight fluorescent lamps, a twenty-four hour timer, one
Auto/Off/Manual switch to control the
lights On/Off cycles and three switches
to enable up to a total of 8 lamps.
Refer to Figure 1-12 on the following
page. The electrical schematic for this
option is included at the end of this
manual.
Program the timer as follows:
1. Set the lamp control toggle switch
to Auto. This will operate the lights
based on timer settings.
2. Set the Off trippers by pushing
them outward from the center of
the dial to control the desired off-
time. During the Off time, the
Lights Off indicator will light.
3. Set the ON trippers by pushing
them toward the center of the dial
to control the desired On time. The
orange or red band is exposed when
the trippers are on.
Note All lamps are controlled by the timer when the Auto/Off/manual
switch is in the Auto position. By default, lamps 3 and 6 are controlled by
the Auto/Off/ Manual switch. The other three light switches
enable/disable the additional lamps to operate with the Auto/Off/Manual
switch. s
Environmental Chamber 1-9Thermo Scientific
Section 1
Installation and Set-Up
Door Light (Optional)
Figure 1-11. Door Light Timer
The accessory outlet is powered by an independent line cord, thus will be
energized whenever its line cord is connected to a power source. Any
devices using the accessory outlets must be approved to operate in the
environment the cabinet is set to control. Additionally, the outlet is
capable of providing up to 16A at 230V.
Accessory Outlet
(Optional)

1-10 Environmental Chamber Thermo Scientific
Section 1
Installation and Set-Up
Figure 1-12. Door Light Configuration
Door Light (Optional)
continued

Environmental Chamber 2-1Thermo Scientific
Section 2 Start-Up and Operation
Main Power Switch and Indicator Light
The main power switch controls power to the incubator. The main
power indicator lights when the power switch is on and the unit is
receiving power.
Refrigeration Switch and Indicator Light
The refrigeration switch controls power to the refrigeration system. The
refrigeration indicator lights when the refrigeration switch is on and the
compressor is receiving power.
Defrost Switch and Indicator Light
The defrost switch controls power to the defrost system. Setting the
defrost switch to Auto will provide two 15-minute defrost cycles during
a twenty-four hour period. The defrost indicator lights when the defrost
switch is on and the incubator is in a defrost cycle.
Caution The defrost switch must be set to Auto when the temperature
setpoint is 10°C, or below. s
Cool Indicator
The Cool Indicator is illuminated when the refrigeration system is acti-
vated.
Heat Indicator
The Heat Indicator is illuminated when the heater is activated.
sample port
Co2
alarm
EZ
WATLOW EZ-ZONE
Overtemperature
Safety
Undertemperature
Safety
Figure 2-1. Environmental Chamber Control Panel (shown with optional CO2control

2-2 Environmental Chamber Thermo Scientific
Section 2
Start-Up and Operation
Overtemp Safety Control, Indicator Light, and Audible Alarm
The overtemp safety thermostat should be set slightly above the operat-
ing temperature of the incubator. In the event of an overtemp condition,
the overtemp safety thermostat will:
• Activate the audible alarm and the overtemp indicator light.
• Interrupt power to the heaters and maintain the incubator’s cabinet
temperature at the overtemp safety control point.
Note The overtemp control is not directly calibrated. The numbers on the
dial are for reference only. s
If an overtemp condition occurs, the alarm can only be silenced by rais-
ing the overtemp safety thermostat setting. However, the cause of the
problem must be determined and corrected before normal operation
under the main temperature controller is resumed.
Undertemp Safety Control, Indicator Light and Audible Alarm
The undertemp safety thermostat should be set slightly lower than the
operating temperature of the incubator. In the event of an undertemp
condition, the undertemp safety thermostat will:
• Activate the audible alarm and the undertemp indicator light.
• Interrupt power to the refrigeration system and maintain the
incubator’s cabinet temperature at the undertemp safety control
point.
Note The undertemp control is not directly calibrated. The numbers on
the dial are for reference only. s
If an undertemp condition occurs, the alarm can only be silenced by
lowering the undertemp safety thermostat setting. However, the cause of
the problem must be determined and corrected before normal operation
under the main temperature controller is resumed.
The Watlow temperature controller’s upper numerical display shows the
actual temperature inside the incubator chamber. The lower display shows
the operatign temperature setpoint.
Changing the Setpoint
To raise or lower the setpoint, press the Up or Down Arrow.
Temperatures are set in 0.1°C increments.
Set the Operating
Temperature