Ovens are basic instruments in any biological and industrial laboratory. They allow a T range between ambient T and 250-300°C, while incubators can reach a max T of around +70°C.
Thermostatting. In the ovens, thermostatting can be obtained with different methods of air circulation: natural convection, forced and guided circulation. WS series ovens are with guided circulation, AC, TO, KWAV models are with forced circulation.
Analyses at temperatures between ambient T and 300°C are carried out in biotechnological research, in the food, pharmaceutical and cosmetic industry, or in all fields that require an extremely precise temperature control, an excellent repeatability and the documentation of analysis processes.
When choosing the ovens, it is important to know the requested T control type, whether or not freely programmable T profiles are necessary, or if a heating system for predetermined T and times is sufficient. In addition, each line includes table or floor instruments and appliances of small, medium and large dimensions.
WS series consists of universal ovens, with guided circulation and digital control; they are of medium-small volume (from 9 to 200 L) and represent an ideal solution for different thermostatting requirements within a T range from +30°C to +250°C.
WS ovens can be used for drying or heating, for product ageing tests and for quality control analyses. Suitable for GLP (Good Laboratory Practice).
TO series (Thermostatic Oven), with forced air convection, also consists of universal ovens, of medium-large volume (from 100 to 1000 L), with structure entirely in stainless steel, and controls and options that make it a high level line. Especially suitable for GLP (Good Laboratory Practice).TO ovens can be used for drying or heating, for product ageing tests, for quality control analyses or for sterilizing.
Sterilization refers to any process that completely kills all micro-organisms, spores included; a material is considered sterile if the sterility safety level is < 0-6; different systems are available according to laboratory or hospital equipment to be sterilized, among which the main types are X-rays, saturated steam in autoclave and dry sterilization in ovens.
AC series (Auto Cycle), with forced air convection, consists of sterilizing ovens, with automatic cycle control. They are of medium-large volume (from 100 to 1000 L), with structure entirely in stainless steel, and controls and options that make them high level ovens. Especially suitable for GLP (Good Laboratory Practice). Like TO series, they guarantee precise operating T stability and and highly homogeneous heat distribution (high T uniformity). Steam can be rapidly eliminated through an exhaust vent.
T data recording can be conducted in combination with the electronic video graphic recorder (with the possibility to print the cycle) and RS8-RS communication interface.
AC series standard version is equipped with a programmer, in which the operator can programme and memorize multiple sterilization cycles, through the Auto Cycle function, that ensures seamless cycle execution for the exact time and temperature values as set by the user: in case of variation of process value from set point value, due to any reason causing malfunction, the device repeats the cycle entirely, continuously displaying process value.
AC series (Auto Cycle) is also available in the double door version, with door interlock device, in order to prevent one of the two doors from opening when the other one is being opened; this ensures complete separation between the sterile environment and the technical area.
KW exclusively has microprocessor electronic digital controls, with RTD PT 100 probe, class A. They allow quick heating and a precise internal T control, even when dealing with numerous and/or large samples, and are suitable for processes that require automatic execution of T programmes.
KW does not deal with mechanical thermostatting, which would allow savings, but implies wide fluctuations (thermal instability) and longer heating times.
T control and conformity to GMP, GLP in ovens
Today, most laboratories are accredited or under certification process. Due to this, there is an always greater demand for valid controls based on GLP. KW offers calibration certificates, documents for installation qualification (IQ) and operating qualification (OQ) and authorization support in situ for all RedLine models.
In order to ensure an accurate T measurement, it is necessary to make use of a perfectly calibrated system. Only a calibrated (and calibratable) system will be able to ensure that the electrical signal coming from the probe shows a correct and repeatable temperature value on the basis of the last calibration values.
All KW ovens, sterilizers, desiccators and dryer cabinets are suitable for the performance of activities linked to implementation of "Good Laboratory Practice", for accreditation and periodical calibration of the instrument.
KW ovens are currently provided with PID (proportional, integral, derivative) electronic thermoregulators with LED digital indicator, obtaining maximum T stability and maximum safety against excessive fluctuations, overshoot, etc. and password against a accidental manipulation, making it impossible to modify PID parameters. These parameters therefore have a considerable impact on the quality of thermoregulation and have been optimized for each oven model and memorized in EPROM.
T stability and uniformity
Thermal stability is obtained with PID control and with low thermal power density heating devices and with thermal power regulation by means of SSR (solid state relay); TO and AC series use the Economy Switch, in order to obtain three different heating levels, according to the desired thermostatting temperature (set point) for maximum stability of the controlled parameter and minimum energy consumption.
Thermal uniformity in ovens is guaranteed by bilateral circulation of thermostatted air, following a particular aeraulic system, created through a specific architecture of the internal chamber. Furthermore, a continuous regulation system for the adopted centrifugal fan speed is available upon request. They also allow shorter heating and recovery times compared to guided convection, maximum uniformity even at full load, and considerable time saving.
Memorization of thermal cycles
When requested, in the most advanced models TO/AC, it is possible to memorize severaltemperature-time pairs, for the creation of thermal cycles. The electronic instrumentation used is highly versatile with a ramp/stasis function able to ensure high performance.
Designed to offer high control performance, these instruments represent the complete solution for a large variety of applications, such as the control of sterilization,
desiccation, depyrogenization, drying cycles, applications that require a precise control of heating and process protection alarms.
The configuration software simplifies instrument programming, parameter adjustment and programme editing.
The complete configuration of the instrument can be saved and downloaded onto the instrument itself providing a quick and reliable way to maintain settings.
There are 90 simple programmes, each of them containing:
- 99 segments - 14 time-based events.
Events on break => it is possible to associate to each segment the ON or OFF condition of one or more programmed outputs such as event on break. It is possible to set several wait-bands.
Ramp function Tracking =>if process variable is outside the programmed wait-band, ramp execution is stopped. The programme starts again when process variable is back into the wait-band.
Guaranteed Soak function => during a stasis segment of programme, the material is kept at the set temperature for the entire programme. If process variable is outside the programmed wait-band, stasis period is interrupted.
Stasis period starts again when process variable is back into wait-band. Each segment can have different wait-bands.
Safety standards adopted are of the highest level and are meant for both product and operator. All RedLine standard models are equipped with an overtemperature device, with probe and regulation independent from the adopted control system, with visual indication panel, in conformity with DIN 12280 standards, class 3.1.
Upon request, a dual safety system (for TO and AC series) is also available: an additional digital electronic safety system, that intervenes on the set T, while continuing to adjust it when the alarm is going off.
Documentation attached to each oven can be provided upon request with the document of individual calibration carried out during manufacturing, using SIT approved instruments.
Flexibility of use
Application versatility, together with a wide range of accessories, is meant to satisfy present and future needs.In brief, it is possible to programme: thermostat controls in continuous, thermostat controls in continuous starting from a time indication (auto-start), thermostat controls during given periods of time (auto-stop), possibility of multiple step programmes (different T and times in succession, Multi Cycle), possibility to repeat temperature/times and programmes cycles (Auto Cycle).
Tubular support for table models; pivoting wheel kit with brake for floor models; daily or weekly timer with on and off switch programming; internal-external hole for control probe access; adjustable opening valve, for elimination of steam (for TO and AC series); cartridge sterile filter (only for AC series); multi-ramp temperature programmer; RS8 serial interface; min/max T alarm devices (only for WS,TO,AC series); electronic digital video graphic T recorder; RTD Pt00 additional probe, complete with connection cable with external system for T acquisition and recording and other parameters/events, such as T-GUARD and SensiNet®, or similar systems; probe complete with -0 mA converter, mounted on DIN bar for connection to external recording system; second electronic digital regulator, for regulation and safety against overtemperature, with possibility of digital setting, RTD Pt 100 Ohm input, completely independent from the main control system, prearranged for possible activation of alarm device;
KW Engineering special executions, etc.
Reliability and lifespan
Internal chamber in AISI 304 stainless steel (or AISI 316), for all series, glossy barium construction and same for shelves, in perforated sheet steel, or stainless steel wire. For maximum resistance to corrosion.
Internal chamber with rounded edges for easy cleaning and maximum hygiene.
External cabinet is in painted sheet steel. (WS), or brushed AISI 304 stainless steel (TO,AC,KW _ AV); key lock handle for maximum operating security.
Low energy consumption, with excellent insulation with natural mineral fibres and/or equivalent and with PID regulation and Economy Switch.
Heating system with armoured or finned tubular heating elements with low thermal power.
Air exchange (optional): adjustable through a cursor placed on the control panel that regulates a throttle valve located on the exhaust. In addition to the ovens described above, KW manufactures
Dryer, desiccator cabinets
These appliances are suitable for multiple applications, in agrifood and industrial laboratories as well. Their technical, structural and functional characteristics are very similar to those of TO and AC series ovens.Sterile preserving cabinets.
They allow preservation of sterile material by means of germicidal irradiation lamps. The access door's frame is in aluminium and the panels are in smoke grey glass (for operator's safety) and is equipped with sealing gaskets.