KeyPad service manual
Rev.1.1
16
1.7 Controller General Description
The following figure shows a general block diagram of the KeyPad controller and
all the interaction between components. Each part will be explained in detail in a
different section of the document.
ANALOG to DIGITAL
CONVERSION
POWER MODULE
HEATER CIRCUIT
CPU Module
KEYPAD
+ 5V
(to all circuit)
AC
To Heater (Ext.)
CNTRL
DATA
RTD SENSOR
Signal_
Out
Selector
LCD Display
DATA
Figure 5:
General KeyPad block diagram
The KeyPad controller system is composed of a keypad to enter information
regarding set point temperature and controlling time to a CPU, which controls the
Digi
PREP
block (Jr, MS, HP or HT). A diagnostic test procedure is available and
will be discussed in CPU diagnostic section.
