Electronic Key Pad Timer Units; Mechanical Dial Timer Unit; Shutdown, Steam Generator Blowdown,And Float Cylinder Rinse - Cleveland steamcraft 21-CET-8 Service Manual

Page 68 Model 21 -CET-8 Service Manual

Shutdown, Steam Generator Blowdown,and Float Cylinder Rinse

Electronic Key Pad Timer Units

Use of the Key Pad Timer is explained in Chapter 3. Once a steaming time is set, and
START/STOP is pressed, the timed cooking cycle starts.
1. Contacts in the control panel close to energize the condenser solenoid and heater
contactor.
2. The compartment thermal switch stays open until the compartment heats up to
operating temperature (190°F). While the thermal switch is open, countdown is
delayed. The timer display alternates between PAUS and the set time.
3. When the compartment reaches operating temperature, the thermal switch closes
and the timer begins to count down. The panel displays the time remaining in the
cooking cycle,
4. Whenever the cooking compartment temperature drops below 190°F, the
compartment thermal switch opens. This stops timer countdown and the panel
alternately displays PAUS and the remaining time. When the compartment
returns to operating temperature, countdown continues.
5. When the timer counts down to 00:00, as indicated on the panel display, the timer
opens its contacts to deenergize the heater contactor and condenser solenoid.
The buzzer sounds until the operator presses the START/STOP key.

Mechanical Dial Timer Unit

When the TIMED/MANUAL switch is set to the TIMED position, the 3-second timer
and buzzer circuits are energized. The buzzer energizes through the TIMED/MANUAL
switch, timer control contacts L1-T3, and 3-second timer. After 3 seconds the 3 -
second timer contacts open, silencing the buzzer.
Use of the dial timer is explained in Chapter 3 . Once a steaming time is set, the timed
cooking cycle starts.
1. Turning the timer dial to any position other than 0 closes contacts L1-T1, energizing
the condenser solenoid and beater contactor. Timer control contacts L1-T3 open
to reset the 3-second timer.
2. When the time set on the dial elapses, the timer control points to 0. Contacts L1-T1
open to deenergize the heater contactor and condenser solenoid. Timer contacts
L1-T3 dose to set the 3 -second timer in operation and cause the buzzer to sound.
Typically, when the SteamCraft 3.1 is shut down at the end of a shift, only the
ON/OFF switch is set to OFF. The main power switch remains ON. During such a
shutdown, the steam generator blowdown and float rinse cycle run automatically.
Figure 5-3 compares water flow through the system for normal fill to water flow during
the blowdown and rinse cycles.
Printed 12/90