Pitco SEH50, Техническое обслуживание и развернутые схемы компонентов

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5
L22-238 Rev 0 (08/03)
US
CAN
GB
If the probe is suspect, check its resistance and the oil/air
temperature at which it was taken. Compare these values
on the chart below.
If the probe returns an open circuit or 0 Ohms reading it
should be replaced. If the resistance varies more than 30
Ohms when being checked between 325-375°F the probe
will give a false temperature reading on the computer and
should be calibrated (up to 10°F) or replaced. However,
it will continue to operate at a slightly higher or lower tem-
perature.
Allow the oil to cool and check the probe resistance at a
lower temperature. As can be seen from the chart a greater
variation can be tolerated at a lower temperature.
Heat Demand Contactor:
The heat demand contactor has a 24VAC coil and will
energize when the correct voltage is supplied to the coil.
When energized, the contacts will close, allowing current
to flow through the elements. The coil resistance is 192
ohms out of circuit.
Hi Limit:
The hi - limit switch is a normally closed switch until the
temperature at the hi-limit bulb reaches 425°F ± 20°F.
WARNING!
This test should be performed by a qualified
technician only! Monitor the fryer closely. This
test will cause the oil to heat past the normal
operating temperature and can cause damage to
the machine and its operator if care is not taken.
WARNING!
This test will cause the elements to heat
continuously. Remove test resistor when test is
complete. Leaving the test resistor in the fryer
could cause damage to equipment and/or personal
injury.
To test the hi-limit, use a 2k
Ω
- 5k
Ω
resistor to simulate
a 230°F - 275°F temperature. This will cause the
elements to heat continuously until the hi-limit trips or the
fryer is turned off.
•If the fryer is equipped with a computer or digital
controller , plug the resistor in at connector J41
behind the front panel.
•If the fryer is equipped with a solid state
controller behind the door, plug the resistor in at
connector J43 behind the front panel.
If the switch does not trip between the prescribed
limits it is defective and should be replaced. Once
tripped, the switch cannot be reset until the oil has
cooled to approximately 375°F + 20°F. If the
switch does not reset after oil has cooled it is
defective.
Once the oil has cooled the hi-limit reset button
must be pressed to reset the hi-limit relay on CE
and export units only.
Drain Valve & Return Valve Switches:
These switches are a magnetically operated
proximity switches. When the Drain Valve handle is
moved to the open position, the Actuator will move
away from the switch causing the switch to open.
When the Drain Valve is closed the switch will
close.
Opening the RED return valve handle will close the
proximity switch causing the "pump on" relay to be
energized. The pump will begin to pump. Closing
the return valve handle will de-energize the relay
and the pump will stop pumping. These switches
can also be checked with an Ohm meter. The
normal gap between the Actuator and the Sensor
switch on the valve handle is
1
/
8
" -
1
/
4
" (3 - 6mm).
Transformer:
Transformers are multiple input voltage 24 volt output
voltage and can be checked by reading the input and
output voltages. A quick check for 24VAC can be
done at the relay board behind the computer. The
AC led will be lit if the F1 fuse is good and the board
is receiving 24VAC
Elements:
Each Element has three coils inside it, check all element