Sequence Of Operation; Cooking Control, Solid State Or Computer - Vulcan-Hart ERO15 Service Manual

SEQUENCE OF OPERATION

Refer to schematic diagram 8810 for Cooking
Control and Filtering System operation.

Cooking Control, Solid State or Computer

FRY CYCLE - LIQUID SHORTENING
If using solid shortening, the control should be
programmed to use the solid shortening MELT
CYCLE . During the MELT CYCLE, the control will
cycle the heat on/off in short intervals. This will
gradually heat and liquify the shortening until it
reaches a temperature of 135 / F. Melt cycle default
times are:
• Liquid L = 4 sec on, 11 sec off (default)
• Solid S = 2 sec on, 13 sec off
• No melt 0 = 100% on.
On solid state controls only, CY (cycle) will be
displayed before shortening letter designation and
zero represents none (no melt).
The control then resumes normal operation as
described in this sequence.
1. Conditions.
A. Fryer connected to correct supply voltage
and is properly grounded. Separate
connections are required for each section
of the battery.
B. Fryer connected to a separate 120VAC
source for the pump motor and
transformer. Required for all filtering
system fryer batteries.
1) 120/24VAC transformer energized.
C. Internal fryer circuit breakers ON.
NOTE: 208 and 240VAC models at 24 KW
only.
D. Power switch off.
E. Shortening at proper level in fry tank and
below last set point temperature used.
F. Cooking control is setup properly and
ready to use.
G. Manual drain valve closed (drain valve
interlock switch N.O. is closed).
H. Tilt switch contacts closed (N.O. - held
closed with heating elements lowered).
I. High limit thermostat closed.
2. Turn power switch on.
A. Supply voltage energizes:
1) 1CON and 3CON thru high limit
thermostat and tilt switch.
ER SERIES ELECTRIC FRYERS - ELECTRICAL OPERATION
2)
3. Cooking control powered at pin C2-1 (24VAC)
and is jumpered to pin 6 (heat status). The
control initializes and performs a diagnostic self
check.
NOTE: If the control passes self check, then
the outputs are energized and operation
sequence continues. If control does not pass
self test, the control will display the appropriate
message for the problem, disable the keypad
and the electronic alarm will sound
continuously. Refer to SOLID STATE or
COMPUTER CONTROL under
TROUBLESHOOTING.
A. Cooking control evaluates the input from:
Heat status at pin C2-6; Drain valve
interlock at pin C2-5; And temperature
probe at pins C2-3 and C2-4 (high & low).
B. If the inputs to the control are valid and
the shortening temperature is below set
point, the heat demand output (24VDC) at
pin C2-8 is then activated and power is
applied to P3 (heat demand control, Triac
energized) on the control interface board.
1)
4. Shortening reaches set temperature.
A. Cooking control de-activates the heat
demand output (24VDC) at pin C2-8 and
power is removed from P3 (heat demand
control, Triac de-energized) on the control
interface board. With power removed from
P3, the heat output at P6 (heat demand
Triac) is also removed.
1)
5. Cooking control cycles heat output on
shortening temperature until power switch is
turned off, heating elements are raised or a
high limit condition occurs.
NOTE: Steps 5A and 5B discuss open high limits.
For additional information on cooking control error
messages, refer to SOLID STATE or COMPUTER
CONTROL under TROUBLESHOOTING.
Page 27 of 48
R2 power relay coil and R2-2 N.O.
contacts close.
Heat output (24VAC) at P6 (heat
demand Triac) is activated on the
control interface board. R1 heat relay
coil energized and R1-2 N.O.
contacts close.
a. 2CON and 4CON are energized
and heating elements are
powered.
2CON and 4CON are de-energized
and power is removed from heating
elements.
F35613 ( September 2003)