Range
- Not Controlled
- Ambient to 95% RH as limited by 40º C dew point
- 20% to 95% RH as limited by 3º C and 40º C dew
points
- Special: Chemical desiccant drier system
4.0 INSTRUMENTS AND CONTROL SYSTEMS
(A) Control Logic
All control relay type logic shall be accomplished using low
voltage (24 volts) plug in relays. Defrost functions shall
be controlled by a solid state programmable microprocessor.
(B) Control Panel Enclosure:
All operating controls, instrumentation, functional switches, and
control systems shall be located at a single control panel center
mounted at operator eye level. All operating modes and functions
shall be clearly indicated by pilot lights and legibly identified
by permanently engraved legends. The functional switches and all
operational control settings shall be mounted in a recessed area of
the enclosure behind a lockable, hinged, transparent cover to
protect against accidental mishaps and unauthorized tampering. The
recessed control panel section of the enclosed shall be hinged for
easy opening by authorized maintenance personnel. Once this panel
is swung open and the top section of the control center is removed,
all enclosed control circuit devices shall be readily exposed for
simple maintenance purposes. Control Panel must be stamped with UL
approval.
(C) Main Temperature Control:
Shall be an all solid state, microprocessor-based, proportional,
electronic controller, which utilizes a precision, platinum
resistance thermometer (RTD) for sensing. Automatic reset and rate
functions shall be incorporated to compensate for error due to load
variations. Operating temperatures shall be easily adjustable by
up-down keypad type indicator buttons. The value shall be displayed
by a digital panel meter; actual temperature shall be displayed on
a large, bright digital read out. The system shall be capable of
setting and reading temperatures to readable accuracy of (0.1 C)
one-tenth of a degree Celsius.
(D) Alarms:
1.Temperature Safety Limit Alarms: In addition to the main
temperature control system described above, an over and under
temperature alarm system shall also be provided on the control
panel. This alarm system shall be completely independent of the
main controller and shall activate in the event the room
temperature becomes out of tolerance in either direction. The
system shall contain separate high and low alarm set-point and the
digital indicator shall be read directly in degrees Celsius with
.01 increments. The alarm system shall be adjustable over the full
range of the room. If an alarm is activated, an audible alarm will
sound and a "High Temp" or "Low Temp" indicator
will be illuminated. The alarm will sound until acknowledged by the
operator by depressing a reset button. If the high alarm is
activated, power to the room heaters will automatically be cut off
from the conditioned space. The Low Alarm will deactivate the
cooling valves.
2. Remote Contacts: Isolated contacts shall be available for
connection to building alarm monitor (BAS) equipment to give remote
signal in the event of either high or low alarm actuation.
3. Power Failure Alarm: A rechargeable battery operated power
failure alarm shall be included that will give both audible and
visual signals in the event power is cut off from the environmental
room.
4. Inside "Panic" Alarm: Shall be provided which will
consist of a red "mushroom head" type push-button located
inside the room near the door. When pressed, this button shall
sound an alarm outside the environmental room.
(E) Chamber High Temperature Safety:
In addition to the High Temperature Limit Alarm, a separate
temperature switch shall be provided as an
Over-Temperature-Cutout to protect the Environmental Room from
thermal damage. This device shall be
adjustable but always set for a maximum value of 55 C. If actuated
the circulation fans, lights, and all heaters
will be electrically deactivated.
(F) Humidity Controller:
When relative humidity control is specified, a completely solid
state, proportional, electronic humidity controller will be
supplied. Automatic reset and rate functions shall be incorporated
to compensate for errors due to load variations. The relative
humidity control point shall be set by a keypad with a digital
indicator, and both the humidity set point and the actual relative
humidity shall be displayed on a bright, digital panel meter,
separate from the readout used for temperature. The system shall be
capable of setting and reading relative humidity to one-tenth of a
percent RH. Sensor shall be a variable capacitance transducer.
Accurate to + 1%
(G) Profile Programmer (Optional)
When specified, the control system shall include a microprocessor
based set point vs. time profile programmer.
(H) Recorder:
A synchronous motor driven circular chart recorder shall be
provided to continuously indicate control conditions within the
room.
The Recorder shall be microprocessor based and programmable to
achieve the proper parameter ranges and time bases. Recorder shall
be Honeywell 10" diameter Model DR4300.
(I) Computer Interface: When specified, digital computer
communication interfaces shall be provided to enable user to
monitor and record process variables. RS-232 or 485 format is
available
5.0 CONDITIONING PLENUMS
(A) Ceiling Conditioning Plenum:
Room air shall be completely conditioned in a ceiling mounted
plenum to maximize floor space. The multiple parallel fans shall be
driven with high efficiency PSC type motors easily serviced from
inside the Room. The fans shall recirculate the room air
continuously to ensure temperature uniformity. Air circulation
shall be highly uniform in the working space to ensure temperature
uniformity. The ceiling plenum shall contain heaters, copper tube
with aluminum fin evaporator coils and humidification apparatus, as
required, and condensate drain pan.
Ceiling material shall be easily removable Acrylic egg crate and
shall be constructed of high grade, non-corrosive material.
(B) Electric Heater (optional):
Shall be non-corrosive, low-watt density, finned elements, which
operate in the black region of the optical spectrum.
(C) Steam Humidifier (optional):
The addition of water vapor shall be made into the conditioning
plenum and not directly into the room area. Water vapor shall be
provided with a low pressure Steam Generating type humidifier with
built in safety protection, automatic water level control valve,
and a safety overflow. The system shall be self-cleaning, with
microprocessor control. The low-pressure vapor generator shall be
manufactured from corrosion free materials.
This system shall be connected to the customer supplied
Deminerialized or RO water supply.
(D) Dehumidification (optional):
Moisture removal shall be accomplished by means of a specially
designed, direct expansion refrigeration coil located in the
conditioning plenum. The coil shall be designed for effective
latent heat removal with a minimum removal of sensible heat. The
dehumidification system shall be non-freezing and shall therefore
produce a low humidity condition limited by dew point of 3 C.
(E) Chemical Drier (sub-freezing Dew Point Capability,
optional):
When ultra low humidity ranges are required necessitating a
sub-freezing dew point condition, a chemical dehumidifier shall be
provided. Chemical dryer shall be a continuous, dry desiccant,
fully automatic absorption, capacity of the refrigeration system
shall be increased to adequately neutralize the sensible heat load
imposed by the chemical dryer over the entire environmental
range.
(F) Vapor Barrier (optional):
When specified, all seams of humidity controlled rooms, when
assembled, shall be sealed against air and moisture entry with a
silicone silastic sealing compound. The sealant shall be flexible
when cured to allow for thermal expansion and contraction over the
entire environmental range.
6.0 FORCED AIR VENTILATION SYSTEM
A forced air exchange ventilation system shall be provided, when
required, for various applications consisting
of an independent exhaust blower and adjustable intake filter
port. The intake filter port shall be easily replaced.
The amount of air exchange shall be:
15 CFM 25CFM Other _____________ of indoor ambient air conditioned
air.
7.0 CONSTRUCTION
(A) Walk-in rooms shall be prefabricated, all metal clad,
sectionals constructed and designed for easy, accurate field
assembly with provisions to facilitate disassembly for relocation
and to add extra panels to increase size.
(B) Panel Construction: Panels shall be made in 11½",
23", and 46" widths and be interchangeable for fast and
easy assembly. They shall consist of interior and exterior metal
pans precisely formed with metal dies and checked with gauges for
uniformity.
Between the double walls shall be 4" of foamed-in-place
urethane insulation, which will provide great strength and
rigidity. No wood, plastic, or metal framing shall be used, thus
avoiding wall heat transfer loss and thermal gradients. Panel edges
must have tongue and groove interfaces to assure a tight joint. A
flexible vinyl gasket shall be fitted on the interior and exterior
of each panel along each tongue edge to provide sealing at each
joint. Panels shall be UL approved.
(C) Panel Locking Devices: All panels shall lock together from the
interior by self-contained cam-lock fasteners. A single hex wrench
tool shall be the only tool required for erection. Batten strips,
pressure clips, or other fastening hardware shall not be an
acceptable means of covering joints or required in joining panel
sections.
(D) Insulation: Four (4") of foamed-in-place rigid urethane
with a thermal conductivity factor "K" of not more than
0.12 BTU/ Hr/ Sq. ft. shall be between the double walls. The rated
"U" factor shall be 0.03 ("U" factor determined
by dividing "K" value by nominal wall thickness
-4"). Insulation shall have an "R" value of not less
than 33. Foamed-in-place urethane shall be used to add strength and
rigidity to the metal
(E) Walls: Note: The process of foaming provides the most positive
adhesion of insulation to metal pans available on the market. The
process of applying metal to board urethane under pressure with
glue is not satisfactory and can result in eventual delamination of
metal from insulation under high temperature and humidity.
Foamed-in-place urethane construction results in a lightweight
room, when completed, and decreases erection costs and final
building weight load. Urethane used in this specification shall UL
fire test approved and when specified shall have a low flame spread
rating of 25 or less.
Only non-CFC blowing agents shall be used to foam these
panels.
7.1 Doors:
(A) The door shall be in-fitting, flush mounted, constructed as
described in 7.0 above. Door swing shall be right hand, left hand,
as required for installation convenience. The door openings will
be
36" x 78" 48" x 84" Special
:_______________________________
(B) Gasket:
The door gasket shall be thermo-plastic with magnetic steel core.
Gasket shall be on both sides and the top of door. An adjustable
rubber wiper gasket shall be on the bottom of the door. The
magnetic force of the gasket shall form a positive
air-tight seal.
(C) Hardware:
The door hardware shall be heavy-duty with high luster finish. The
hinges shall be of the self-closing type with durable stainless
steel pins and self-closing nylon cams. The door handle and latch
assembly shall be of the automatic closing type. A safety release
mechanism shall be provided on the inside of the room preventing
personnel from being lock from the outside. Keyed lock cylinders
and padlock latches shall be incorporated with the door latch and
handle assembly.
(D) Heated Gasket:
A heater shall be built into the perimeter of the jamb to prevent
the door from accumulating ice and freezing temperature. (Rooms
operating below 0 C.)
(E) Window:
A multi-layer, heated thermal pane window shall be mounted in the
door with a minimum viewing area of:
12" x 12" 14" x 14" 14" x 23"
Special________________
7.2 Floors:
(A) Standard:
The floor shall have the same construction as described in 7.0. In
addition, it shall be rated for 600lbs/sq.ft distributed load. The
interior floor surface shall be heavy gauge galvanized steel.
When Specified a Non-Skid Coating is applied to cover the floor
area
(B) Building Floor:
The modular room wall panels shall be provided with sealing strips
to interface with an insulated building slab or a flat floor area.
The system shall allow for properly sealing between the existing
insulated floor and room walls preventing air infiltration and
environmental losses.
(C) Floor Coverings:
Interior floor shall be totally covered with removable, open tread
design, 1/8" thick, PVC rubber matting. Open diamond design
permits easy cleaning with floor mat in place
7.3 ROOM SURFACE FINISH:
(A) Standard: Interior and exterior walls unless otherwise
specified shall be manufactured with a hard durable white baked
enamel coating on galvanized steel surfaces. Interior floor surface
shall be natural 14 gauge galvanized steel.
(B) Special Finishes:
1) Interior and exterior walls when specified
shall be manufactured with .040" thick embossed aluminum
surfaces with natural finish. Interior floor surface shall be
natural 14 gauge galvanized steel.
2) All interior and exterior walls (exposed
surfaces only) shall be .040" aluminum faced with a hard,
durable factory applied painted finish. The color shall be white or
gray with a painted finish of either epoxy or acrylic enamel.
Closure Panels of matching material will be provided to fill in
between customer's building and Environmental Room.
8.0 LIGHTING
(A) Lighting systems shall utilize cool white fluorescent lamps.
Lamps and ballasts shall be enclosed in low vapor proof fixtures.
The fixtures shall be UL approved. Light fixtures shall be flush
mounted and provided in sufficient quantity for minimum intensities
of 70 foot-candles measured 40" above the floor.
(B) Low temperature electronic ballasts shall be provided for
cold rooms operating below 10 C. Lights shall be installed to
provide uniform distribution of light.
(C) Incandescent, vapor proof lights shall be provide for freezers
operating below 0 C
(D) Light Cycle Timer: An optional 24 hour on/ off cycle timer
shall be provided on the control panel for cycling interior
lighting.
9.0 REFRIGERATION SYSTEMS
(A) The refrigeration system shall be specifically designed,
engineered, manufactured and of adequate capacities to achieve and
maintain the individual room temperature requirements and
performance and shall be balanced in operation with the
conditioning system. The system shall be factory assembled and
tested by Thermmax. It shall also include high/ low-pressure
controls, receiver, sight glass, moisture indicator, replaceable
dryer, thermal expansion valve, and all necessary equipment to
achieve the performance specified.
(B) Compressor: The system compressor shall be a semi-hermetic,
heavy-duty, industrial unit with solid state motor protection
and oil pressure safety control. The compressor shall contain, in
addition, an oil sight glass, a lubrication protection cut-out and
integral suction and discharge service valves.
(C) Condensing Unit: The system shall be furnished with an air
cooled condenser. Fans shall be slow speed, low noise with
metal guard protection.
(D) Water-cooled Condenser: When specified, a water-cooled
condenser shall be utilized in lieu of the air cold system. The
unit
shall be designed to operate on city water of approximately 75 F
inlet temperature and is to include a water saving pressure
regulation valve. The unit shall be designed for tower cooled
building water operating with inlet temperatures of between
60 F and 85 F approximately and temperature rise of 10 F or less.
A three way regulator shall be employed for constant
compressor head pressure regulation.
Control: The refrigeration system shall contain full capacity
control to operate continuously regardless of control system
demand. System shall incorporate a bypass to maintain specified
temperature ranges. Cooling shall be proportionately controlled by
means of the electronic temperature controller modulating liquid
refrigerant feed to the conditioning coil.
(E) Redundant Refrigeration System: When specified a backup 100%
redundant refrigeration including all refrigeration components
shall be used. The two systems will alternate on a periodic
basis with an adjustable cycle time to assure that both
systems are exercised and tested to be functional. On a failure,
the passive system will automatically come on line to maintain Room
temperature. A failure mode alarm will also be activated and the
backup system will now run continuously until the fault is
cleared. The Redundant system control shall be achieved by
means of a programmable microprocessor .
Defrost System: When room temperatures operate continuously
below 4 C, an automatic hot gas or electric defrost system shall be
provided. Defrost cycles shall be controlled by a 24 hour timer
adjustable to determine the number of defrosts per day, and the
duration of each defrost. On freezer rooms operating at -20 C or
below an electric defrost system shall be used.
Outside Condensing Unit: When limited space or other
requirements dictate, the condensing unit shall be remotely located
outside the building. The unit shall be weather protected with an
easy access hinged enclosure, properly vented for adequate air
movement. The system shall also contain head pressure control and
crankcase heaters for proper winterized operation. A NEMA 4
electrical enclosure with disconnect and internal contactor box
shall be located on the housing
10.0 SHELVING
Freestanding wire rod shelving units shall be supplied in the
amount specified. Shelving material shall be chrome plated or
stainless steel and shall be manufactured to high quality standards
to be free of burrs, sharp edges, and protrusions. Each shelf shall
be adjustable in the freestanding rack.
Wall mounted shelving shall be supplied in the amount specified.
Shelving material shall be chrome plated or stainless steel and
shall be manufactured to high quality standards to be free of
burrs, sharp edges, and protrusions.
11.0 ACCESS PORTS
For water, drain line, air or gas lines shall be provided in the
size and quantity specified:
1" 2" 3" 4"
12.0 ELECTRICAL OUTLETS
(A) Vapor-proof, duplex, 115volt, 20 amp GFI receptacles shall
be installed on the inside wall 45" above floor. Each
receptacle shall be wired to a terminal box on top of the room for
connection by others.
(B) Other special:
________________________________________________
13.0 DRAWINGS and MANUALS
Roughing-in approval drawings shall be supplied prior to the
commencement of manufacture; these drawings must be verified and
approved by the customer to assure clearances, utilities, and other
interfaces.
Instructions and Maintenance Manual: A complete comprehensive
instruction and maintenance manual shall be provided with each
room. The manual shall include sequential operating instructions,
routine preventative maintenance instructions, and complete
schematics.
Warranty: A warranty certificate shall be included in the manual
of each supplied room.
14.0 INSTALLATION (Options)
(A) Factory supervision only of installation with labor to be
supplied by others. Thermmax Scientific shall furnish technical
supervision for installation. The purchaser as required will supply
the field labor. Thermmax Scientific's field technical
representative shall supervise the installation of the rooms,
instruct personnel in the proper operation and preventative
maintenance, and shall field check the equipment on start-up.
(B) Complete Installation: Thermmax shall deliver and erect the
environmental room factory supplied equipment and
will have the following responsibilities:
1) Delivery of rooms to their final destination.
2) Assemble rooms complete in place.
3) Interconnect all refrigeration piping and electrical wiring,
which are an integral part of the room assemblies.
4) Start-up and field-test the room operation.
NOTE: Thermmax will not in any way be responsible for
altering existing building walls, conditions or utility
services.
It will be the customer's responsibility to provide the
following on a timely basis:
1) Make the area completely ready for proper and efficient
installation of the room(s). The site location floor must be made
flat and level. The site area must be made clear of all partitions,
piping, obstructions and loose articles preventing the ready
erection and assembly of the environmental room(s) and support
equipment.
2) Furnish the specified electrical service to the local vicinity
of the room, including a fused disconnect. Final connection will be
made by the customer at the Thermmax designated terminal
connection.
3) Provide floor drains and or condensate removal pump system to
remove room drainage.
4) Provide water supply and return line, if required, and make
final connections.
5) Provide any other special utilities and service
connections.
6) Provide all building wall, roof, or floor penetrations.
15.0 VALIDATION
The temperature accuracy and uniformity inside the completed
room shall be measured using 16 thermocouple probes. The probes
shall be placed throughout the internal workspace at strategic
locations no closer than 12 inches from any surface. The probes
shall be calibrated in a 0.1 C water bath using an NT traceable
thermometer. Test data shall be recorded on a Digital Data
Acquisition Recorder system and turned over to operating
personnel.
16.0 Factory Acceptance Test Plan
Thermmax will perform a factory test and inspection on all major
components to assure basic quality, conformance
of design and functional operation.
Each Control Console will be bench tested using a simulator panel
to test all logic functions, control systems function,
and alarm operations.
Each Condensing Unit and Air Unit will be pressure tested for
leaks and checked for design conformance.
When required the customer may elect to be present for factory
checkout.
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