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OPERATION
Heating Control
The oven controller monitors the chamber shelving temperature using a thermocouple temperature
probe extending into the chamber from the back wall. In a vacuum environment, the probe senses
the temperature of the shelf placed immediately above it. Placement of a shelf in close proximity to,
but not in contact with the probe, is crucial for accurate measurement of the shelving temperature in
the vacuum chamber.
The unit uses Proportional – Integral – Derivative (PID) control to avoid significantly overshooting the
setpoint. The rate of heating will slow as the chamber temperature approaches the target temperature. If
the chamber temperature is above the setpoint, the unit uses minimum heating to control the rate of
cooling and avoid dipping below the setpoint.
PID loops also optimize heating rates to compensate for the temperature environment around the
unit. If the unit is operating in a cool room, the controller will increase the length of the heating
pulses. Likewise, when operating in a warm room the unit uses shorter pulses. If the ambient
temperature conditions change significantly, there may be minor over or undershoots as the unit
adapts.
The oven relies on natural heat radiation for cooling. It can achieve a low-end operating temperature
of the ambient room temperature plus the oven waste heat.
Warm Up
Only pre-heat the oven if this is compatible with your application and safe practices. 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. 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.
Heating Cutoff System
The oven is equipped with a thermal cutoff system that automatically cuts off electricity to the oven heating
elements when the shelving temperature exceeds 392°F (200°C). This safeguards the oven in the event of
a failure of the main temperature control circuitry or main temperature sensor probe. The cutoff system will
reset when the chamber temperature drops below its cutoff setting.
Summary of Contents for CVO-2
Page 1: ...Installation Operation Manual CVO 2 Benchtop Vacuum Ovens...
Page 6: ...6 P a g e cascadesciences com Tel 503 847 9047 TABLE OF CONTENTS...
Page 8: ...8 P a g e cascadesciences com Tel 503 847 9047 CERTIFICATIONS...
Page 12: ...12 P a g e cascadesciences com Tel 503 847 9047 SPECIFICATIONS...
Page 20: ...20 P a g e cascadesciences com Tel 503 847 9047 RECEIVING...
Page 30: ...30 P a g e cascadesciences com Tel 503 847 9047 INSTALLATION...
Page 32: ...32 P a g e cascadesciences com Tel 503 847 9047 SYMBOLS...
Page 50: ...50 P a g e cascadesciences com Tel 503 847 9047 MAINTENANCE...
Page 52: ......
