They can be connected in either single-phase or
NOTE: Before starting any service work on
The deep fat fryer must not be fused, but
electric galley equipment, ensure the equipment power
connected to an external circuit breaker equipped
supply is secured and properly tagged out.
with a shunt trip element. The shunt trip element is
Refer to the manufacturers' technical manuals for
connected to the (backup) upper limit thermostat. The
instructions concerning the servicing of the electric
backup thermostat functions when the normal
galley equipment installed aboard your ship. These
manuals also include the methods you should use to
thermostat does not operate properly. When the
remove and replace various heating units, thermostats,
temperature rises to 460F, the backup thermostat will
switches, contractors, and other components of electric
operate and trip the external circuit breaker to
disconnect the deep fat fryer from the power source.
Galley equipment is normally trouble-free. The
most frequent trouble with electric ranges, ovens, and
The heating unit is an enclosed type of element and
deep fat fryers is burnt contacts. As the operating
is immersed directly into the fat to ensure maximum
temperature is met on the thermostat, the contactor will
efficiency. The heating unit is hinged to the back of the
open under a heavy load, causing its contact(s) to arc
fryer for ease of cleaning or for changing the liquid fat.
and burn. Another common problem is corroded
connections due to prolonged exposure to heat and
The pilot light is energized at all times to indicate
grease. You should make a concentrated effort to follow
that power is available to the deep fat fryer. The power
the prescribed planned maintenance, and when
on light is only energized when the heating unit is
necessary, perform corrective maintenance.
energized and the unit is heating the liquid fat.
The controls are located inside the deep fat fryer
enclosure. Figure 5-50 is a simplified wiring diagram
The information in the preceding paragraphs is very
basic. There is no standard for the type of galley
of the Mk 721 deep fat fryer.
Figure 5-50.--Wiring diagram of the Mk 721 deep fat fryer.