Cryogenic temperatures without liquid nitrogen
Air-cooled refrigeration systems are engineered to maintain design temperatures of -150°C (Model ULT-7150-9 ) or -140°C (Model ULT-10140-9) in warm ambient conditions: For Model ULT-7150-9, +30°C (+86°F); for Model ULT-10140-9, +32°C (+90°F).
Comparison of temperature distribution in a liquid nitrogen freezer (vapor phase) and mechanically refrigerated cryogenic freezer (i.e., Revco™ Ultima II Model ULT10140-9). Graph represents temperatures (°C) at relative locations within the chamber. Data suggests that 100% of the Ultima II storage space maintains uniform storage temperatures safely below -130°C, while temperature in LN2 vapor system is dependent on storage location.
Safer and more convenient than LN2, Revco™ Ultima II cryogenic freezers are designed for long-term storage of biologicals at uniform temperatures of -140°C and -150°C, safely below the -130°C glass transition temperature of water. They include all features, control and performance attributes of the Ultima II Series freezers, plus many important advantages not available when using LN2:
- Stable cryogenic temperature of -140°C and -150°C without LN2 as a cooling medium
- Patented, single compressor, orbital refrigeration system
- Top-to-bottom temperature uniformity dramatically improved when compared to LN2 vapor
- Lower operating costs than LN2 freezers of similar capacity
- 100% of interior space is usable, with stored samples maintained below critical temperature
- Ample interior volume with capacity of up to 21,600 samples in Model ULT-10140 and up to 14,400 samples in Model ULT-7150 (2 ml vials in boxes)
- Uses standard Revco® inventory racks and fiberboard boxes; see Accessories
The refrigeration system involves an exclusive mixed refrigerant (CFC-free ) autocascade with a single, orbital refrigeration compressor, air-cooled. Downfeed evaporator for most efficient refrigerant flow, and high-capacity air-cooled condenser with dual condenser fans, aerodynamically shaped fan blades. The washable condenser filter keeps fins free of dust to maintain peak cooling efficiency; no tools required for removal.
Exclusive IntrLogic™ microprocessor control system with touchpad data entry and digital display of all functions. Independent operating temperature and high/low limit alarm functions with factory-set defaults for quick start-up, all setpoints adjustable in 1°C increments. Setpoint security system has a key-operated switch for main power and alarm.
Ultima II IntrLogic™ microprocessor control monitor all functions for safe, dependable and economical operation; shown with optional LN2 backup system.
The electrical system has an automatic voltage boost that compensates for low voltage and brownout conditions; on-board power monitoring with digital readout of incoming line voltage; and built-in surge suppressor to minimize effect of voltage spikes from incoming electrical service.
A.I.M. (Automatic Incident Monitor) identifies any temperature deviation beyond alarm setpoints, with rapid flash for current event, slow flash if event was self corrected; A.I.M. archives most deviated temperature. An adjustable safety alarm with automatic, continuous charge battery backup provides full function in case of power failure. Power failure or temperature deviation triggers audible and visual warning . Digital batter indicator displays battery capacity; flashing low battery indicator advises when to replace battery. Touchpad alarm test function physically warms internal probe to simulate alarm condition. RS-232 data port with system software package. Exterior alarm contacts for connection to remote monitoring system.
Monitoring System indicates a variety of out-of-range conditions:
- Lifeguard compressor protection monitors performance and automatically adjusts to internal and external conditions, extending compressor life
- Extreme ambient alert warns if room temperature may affect performance
- Voltage boost indicator advises of low source voltage below safe parameters and indicates voltage boost system is activated
- Surge suppressor indicator advises to check intercept fuse
- Clean filter indicator light advises when to remove and wash condenser filter
Chest Cabinet has a low-profile design for easier access to inventory. The heavy duty counterbalanced lid has an integrated keyed lid lock for security. Double seal lid gaskets minimize frost buildup, and independent sub-lids provide additional protection. Minimum 5" (127 mm) foamed-in-place urethane insulation, closed-cell, CFC-free, protects product against high ambient conditions. The heavy-gauge steel cabinet has a high-impact powder paint finish. Rounded interior corners and recessed heavy duty swivel casters facilitate cleaning. Access port, 1" (25.4 mm) diameter, with cap.
Optional inventory components including racks, boxes and dividers can be ordered separately or as full-load inventory systems, as can optional temperature recorders, LN2/C02 back-up systems, inventory components, validation testing, calibration certificates and associated product. Contact Krackeler Scientific Customer Service for more information.
* No plug provided; requires hardwire connection by customer
All dimensions and specifications subject to change without notice. External dimensions include allowances for cabinet door, hinges, latches, handles, and control panel protrusions.