shelolab SLFHP522-H, Инструкция по установке и эксплуатации

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OPERATION
T
HEORY OF
O
PERATIONS
Heating
The oven temperature controller stores an end-user selected constant temperature setpoint. When
powered, the oven heats the chamber atmosphere to the setpoint. The controller board is wired to a solid-
state temperature probe located in the chamber on the right wall. When the controller detects that the
chamber temperature has dropped below the temperature setpoint, it pulses power to the heating
element.
The oven uses Proportional – Integral – Derivative (PID) control to avoid significantly overshooting the
setpoint. This means the rate of heating slows as the chamber temperature approaches the target
temperature. If the chamber temperature is above the setpoint, the oven uses minimum heating to control
the rate of cooling and avoid dipping below the setpoint.
Additionally, the PID loops optimize heating rates for the temperature environment around the oven. If the
oven is operating in a cool room, it will increase the length of heating pulses to compensate. Likewise,
when operating in a warm room the oven uses shorter pulses. If the ambient temperature conditions
change significantly, there may be minor over or undershoots as the oven adapts.
The oven relies on natural heat radiation for cooling. The oven can achieve a low-end operating
temperature of the ambient room temperature plus the internal waste heat of the oven.
Heating Options
The oven can either heat to and run at a constant temperature setpoint or execute a programmable
multistep temperature recipe with ramp up, heat soak, and ramp down intervals.
Air Circulation
The oven continually circulates air internally while powered to maintain temperature uniformity and stability
in the oven chamber and to speed drying rates. Air is forced through vent holes on the right side of the
chamber, blows across the shelf space, and is then pulled into a duct that makes up the left chamber wall.
From there, the air is drawn upward into a heating duct by the action of the blower fan. The oven is
intended to be run as a closed air-cycle system.