Cascade Sciences CVO-10, Руководство по установке и эксплуатации

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OPERATION
Heating Control
The oven temperature controller stores an operator-selected constant temperature setpoint. When
powered, the oven heats the chamber shelves to the setpoint. The controller board is wired to a
solid-state temperature probe located in the chamber on the rear wall. When the controller detects
that the shelf temperature has dropped below the temperature setpoint, it pulses power to the
heating elements.
The controller employs proportional-integral-derivative analytical feedback-loop functions when
measuring and controlling the shelving temperature. PID-controlled heating pulse intensities and
lengths are proportional to the difference between the measured shelf temperature and the current
setpoint. The frequency of pulses is derived from the rate of change in that difference. The integral
function slows the rate of pulses when the temperature nears the setpoint to avoid overshooting.
These ovens rely on natural heat radiation for cooling. The oven can achieve a low-end operating
temperature of the ambient room temperature plus the oven waste heat.
Warm Up
Allowing the oven to heat up with atmosphere in the chamber can result in a significant temperature
drop when heated atmosphere is evacuated from the chamber. To achieve the best temperature
stability and uniformity, allow the oven to heat up under vacuum prior to loading product. This heat
soaks the oven body and insulation masses. Only pre-heat the oven if it this is compatible with your
application and safe practices.
The Over Temperature Limit System
The oven is equipped a heating cutoff system that automatically cuts off electricity to the oven
heating elements when the shelving temperature exceeds 392°F (200°C). This is intended to help
prevent runaway heating in the event of a hardware failure.