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F. Electrical System
The freezer is factory wired. The installer must provide the proper
power source to the system’s electrical control panel. In some
areas voltage can vary to such an extent that damage to a
compressor can result if built in compressor protection devices fail
to react fast enough. A power line circuit breaker, installed in
accordance with local codes, is recommended for such areas. For
details of the electrical system refer to Figure 2.
G. Hydraulic System
A “HYDRAULICS” switch on the operator control (Figure 3) panel
provides a means of operating the hydraulic system. When the
switch is in the “UP” position, the hydraulic pump motor is
energized, producing the required hydraulic pressure to the
actuator to raise the plates, closing them on the products.
Hydraulic pressure increases until it reaches 600 psig, where the
high- pressure control shuts the pump motor off. When products
are frozen they tend to expand. This expansion can cause
pressure locked in the actuator to increase. When this excess
pressure reaches 650 psig, the system relief valve will prevent the
pressure from exceeding this value while maintaining system
pressure in the actuator.
Internal leakage in the hydraulic system will cause the pressure to
drop if the “HYDRAULICS” switch is in the “OFF” position. This will
cause the plates to fall slowly, thereby losing one surface of contact
with products. The syste m is designed to maintain pressure on the
system to make up for such leakage as long as the “HYDRAULICS”
switch is kept in the “UP” position. Therefore, it is recommended
that the switch be kept in the “UP” position when the freezer is in
operation.
Placing the “HYDRAULICS” switch in the “DOWN” position
energizes the solenoid dump valve, reducing pressure in the
system. The plates will move downward due to gravity.
To hold the plates in a given position, the switch would be placed in
the “OFF” position. When the freezing cycle is complete, placing
the switch in the “DOWN” position causes the plates to open up
and permit unloading of the frozen product. Dexron II oil is used in
the hydraulic system. For details of the hydraulic system refer to
Figure 4.