Jenn-Air WW27430 Oven User Manual


 
SECTION 1. COMPONENT DESCRIPTION
COMPONENTS
Meat Probe: Senses the internal tempera-
ture of products during a baking function.
The meat probe is an NTC, or negative
temperature coefficient, which means the
resistance value decreases as the tempera-
ture increases. See meat probe chart below
for resistance values.
MEAT PROBE
Type: Calibration:
NTC Thermistor 9938 ohms (150°F.)
PROBE RESISTANCE VS. TEMR TABLE
Degrees E Resistance
122 18963 ohms
150 9938 ohms
156.2 8846 ohms
165.2 7456 ohms
210.1 3886 ohms
Membrane Switch: The means to make a
switch contact, thus instructing the elec-
tronic control system to perform a desired
function. The membrane switch is a simple
set of two contact surfaces containing
conductive material, one on the back layer
of MYLAR and the other on the front layer
of MYLAR. There is also a center section of
non-conductive MYLAR material that has a
hole punched out of it at each switch con-
tact position. The thickness of this spacer
MYLAR determines the push force required
to close the contacts between the front
contact strip and the rear contact strip.
Typically, the push force required to close a
contact is 12 to 18 ounces.
Electronic Control: A programmable soft-
ware component that controls oven, clock,
timer and various other functions. The
control maintains oven temperatures in
either bake, broil, or clean. It is adjustable to
maintain correct temperature offsets. It is
also programmed with self-monitoring
circuitry, which determines if a potential
unsafe condition is present, shuts the sys-
tem down and displays the appropriate fault
code. Fault codes are covered in product
specifications sections 3 and 4.
Touch Sensor Technology: With this new
technology a positive charge and negative
charge is present around each pad. This
creates an electrostatic field that emanates
around, below, and through the glass front.
When the consumer touches a key pad, this
disturbs the electrostatic field and draws
capacitance energy. This input is read by
the module, which in turn signals the con-
troller to respond, and the desired function
is performed. In order for a function to be
performed, a conductive material must
bridge the gap between the negative charge
present at each pad.
Display Board: Displays time-of-day clock,
oven temperatures, and any other function
programmed into the electronic control
system. The display board also acts as the
input means from the membrane switch
and sends those commands to the power
relay board to process, implement, and
monitor.
Power Relay Board: Contains the intelli-
gence in the electronic control system and
controls all oven functions, clock, timer, ,and
various other consumer programmable
inputs. The PRB has a relay mounted to it
for each function it provides.
Oven Sensor: A device to monitor internal
oven temperature. The sensor has a PTC or
positive temperature coefficient, or a resis-
tance value that increases with temperature.
Allows the electronic control to maintain a
temperature setting through means of
resistance matching with the control-se-
lected temperature. Example: The oven
control is set at 350°F, the oven sensor
resistance at room temperature is approxi-
mately 1060 ohms. As the oven heats, the
16009721 COMPONENT DESCRIPTION 1-1
_1999 Maytag Appliances Sales Company