Vulcan-Hart C24EO3 Electric Steamer User Manual


 
C24EO SERIES STEAMER - ELECTRICAL OPERATION
SEQUENCE OF OPERATION
Schematic diagram AI2851 will be used to explain
the electrical sequence of operation.
Timed Cooking Mode
1. Conditions.
A. Steamer connected to correct voltage and
is properly grounded.
B. Power switch (1S) off.
1) Relay K3 energized. K3 N.C.
contacts open.
C. High limit thermostat closed.
D. Hold thermostat closed.
E. Low water thermostat closed.
F. Temperature control is setup properly and
is ready to use.
G. Door closed (door switch closed).
H. Timer off.
I. Cooking compartment filled to the water
level mark and below hold temperature of
175°F (+/- 5°F).
J. Drain valve is closed (drain lever pushed
in).
2. Press momentary start switch (1S).
A. Limiting contactor (1CON) coil energized
thru high limit thermostat (1TAS).
1) Line voltage is supplied to one side of
heating elements.
B. Relay K2 coil energized thru low water
thermostat (2TAS).
1) K2-1 N.O. contacts close.
a. Power switch circuit is latched.
2) K2-2 N.C. contacts open.
a. Low water light (1LT) and buzzer
are de-energized.
C. ON indicator light (2LT, amber) comes on.
D. Relay K1 coil energized thru door switch
and hold thermostat (3TAS).
1) K1-3 N.O. contacts close and
regulating contactor (2CON) coil is
energized.
a. Line voltage is supplied to other
side of heating elements.
Elements heat.
2) K1-2 N.C. contacts open.
3) K1-1 N.C. contacts open (prevents
timer from being energized during pre-
heat).
3. Steamer reaches 175°F.
A. Hold thermostat opens and relay K1 coil is
de-energized.
1) K1-3 N.O. contacts close and remove
line voltage to heating element
assembly.
2) K1-1 and K1-2 N.C. contacts return to
close condition.
NOTE: Steamer will maintain hold temperature
until a cook time is dialed on timer, door is
opened, or power switch is turned off.
4. Set cook timer to desired time.
NOTE: Timer motor will not run when hold
thermostat (3TAS) is below 175°F.
A. Timer contacts close, timer motor is
energized and timing down begins.
NOTE: Additional time can be set or the cook
timer can be turned off throughout the cooking
cycle. If turned to off, steamer reverts to hold
temperature.
B. Cook light (3LT, red) comes on.
C. Temperature controller energized and
evaluates input from thermocouple.
1) If temperature is below set point,
temperature controller internal N.O.
contacts close and energize
regulating contactor (2CON) coil thru
K1-2 N.C. contacts.
a. Line voltage is supplied to other
side of heating elements.
Elements heat.
5. Temperature reaches set point and the
temperature control’s internal N.O. contacts
open.
A. Regulating contactor (2CON) coil de-
energized and power is removed from
heating elements.
6. Steamer cycles on the temperature control until
cook time expires.
7. Time expires on cook timer.
A. Timer contacts 11 & 13 open, timer motor
is de-energized and timing stops.
B. Timer contacts 11 & 14 close.
1) Buzzer energized thru K2 N.O.
contacts and sounds.
NOTE: The buzzer continues to sound until
timer dial is set to off position or additional
time is set.
C. Timer contacts 21 & 23 open, cook light
(3LT, red) goes out and temperature
controller is de-energized.
F25386 (June 2010)
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