Watlow MINICHEF 2000 - Manual (Page 60)

G l o s s a r y
H a r d w a r e & S o f t w a r e S e t u p G u i d e Wa t l o w M I N I C H E F 2 0 0 0 ■ 5 9
Manual control A way of operating foodservice equipment that requires end-users to
select and use manual setting keys.
Manual Setting keys Keys that allow end-users to manually set time, temperature,
etc., individually.
Menu Set of cooking instructions that can be programmed into the M INI C HEF for end-
user convenience. A menu can include times, temperatures, fan speeds, etc.
Menu Select key A key that allows end-users to access and select from a list of pre-
programmed menus.
On/off control On/off control switches the output either full on or full off, depending
on the input, set point and hysteresis values. The hysteresis value creates a buffer zone
that increases the time interval that the output is off or on. With hysteresis set to 1º the
process value would stay closer to the set point, but the output would switch on and off
more frequently, causing “chattering.”
Operation Mode The end-user mode that occurs after power-up. It allows end-users to
cook foods using pre-set keys and menus. Operation Mode is the M
INI C HEF 2000 default
mode.
PID Uses derivative (rate) control to minimize the overshoot in a Proportional-Integral
controlled system. Derivate (rate) adjusts the output based on the rate of change in the
temperature or process value.
Program Mode The level of programming in which the automatic menus are set.
Programmed menu keys Keys programmed to allow users to choose pre-set cooking
instructions.
Proportional control Some processes need to maintain a temperature or process
value closer to the set point than on/off control can provide. Proportional control pro-
vides closer control by adjusting the output when the temperature or process value is
within a proportional band. When the value is in the band, the controller adjusts the
output based on how close the process value is to the set point: the closer to set point
the lower the output. This is similar to backing off on the gas pedal of a car as you
approach the speed limit. It keeps the temperature or process value from swinging as
widely as it would with simple on/off control. However, when a system stabilizes, the
temperature or process value tends to “droop” short of the set point.
Rate Anticipatory action that is based on the rate of temperature change, and compen-
sates to minimize overshoot and undershoot. See derivative.
Reset Control action that automaticaly eliminates offset, or droop, between set point
and actual process temperature. Inverse of Integral.
Rotisserie Oven An oven that slowly cooks meat on a rotating spit, and allows cook-
ing of single or staggered batches of food.
Shelf Timing Oven An oven with one temperature setting and a timer that permits
individual cooking times to be set for different shelves.
Timer Can accompany any type of food equipment to help time food cooking cycles and
alert users to perform related tasks.