Isothermal Airless Oven Heater System (Split) - Siemens Maxum II Manual

3.4

Isothermal Airless Oven Heater System (Split)

The Maxum II airless oven is used to provide a very stable isothermal oven temperature without
the need to supply oven air to the analyzer. This allows for excellent chromatographic results
while reducing utility costs. The interior of the airless oven is surrounded with heavy aluminum
walls that are embedded with two cartridge heating elements and temperature sensors. The
walls radiate heat to the oven air. The airless oven comes configured as two fully independent
ovens with separate oven doors (refer to figure 3-4). Note: If only one airless oven compartment
is required, then the second compartment is left unequipped without the aluminum walls and
heating elements.
Figure 3-4
The primary explosion safety system within the Isothermal Airless Oven is the heating and
temperature control system. As mentioned above, the oven is heated using two heating
elements embedded in explosion-proof channels within the aluminum walls. The temperature
of these heating elements is detected and limited by two RTD probe sensors that are also
embedded within the aluminum walls adjacent to the heating elements. These probes are
controlled by temperature control circuitry on the Power Entry Control Module (or Detector
Personality Module) and are set below the applicable T-rating such that exposed surfaces will
not exceed the maximum allowable temperature. The locations of the temperature probes and
heating elements are shown in Figure 3-5.
Explosion Protection Safety Standards
Manual, August 2017, A5E02220442001 Rev 8
Airless Oven
3.4 Isothermal Airless Oven Heater System (Split)
Safety Systems - Oven
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