Blodgett MT3255 Series, Руководство по обслуживанию и ремонту

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OPERATION
3---16
NOTE: The switch is located in the front con-
trol compartment. It protects the other
components from hi ambient heat.
If this switch is cold, it should be closed send-
ing power to the single solenoid gas valve (17).
4. When power is applied to the coils of both mo-
tor contactors (3) the contacts close sending
power to the four convection fans (5) located
in the back of the oven.
5. The oven has six cooling fans (18). Two on the
front control panel keep the panel below 140
_
F
(60
_
C). The fan’s airflow is from left to right for
flow through ventilation. The other four, in the
rear of the oven, keep the convection fans from
overheating. The cooling fans start when the
motor contactor powers up and closes be-
tween terminals #13 and #14. Power goes to
the N.C. terminal of a SPDT thermal switch
(19). The switch toggles if the temperature
passing its face exceeds the rating on the back
of the switch and may start the fans even if the
oven is off. If this switch is cold, it should be
made between common and N.C. terminals
sending power to the cooling fans.
NOTE: The switch is located on the ceiling of
the convection fan compartment.
6. The conveyor belt is driven by a closed loop
D.C. drive system consisting of a conveyor
switch (20), 130 VDC motor (21), time display
and motor drive (22) and a #2 Hall effect pick-
up (23). Refer to page 5---1 for pickup trouble-
shooting. The motor speed varies based on
the time programmed into the digital time dis-
play. To slow the belt down, press the down ar-
row key. To increase belt speed, press the up
arrow key.
NOTE: When this component is replaced it
must be reprogrammed for the ap-
propriate tunnel length. Reference
Calibration section page 4---4.
NOTE: This system senses the weight of the
product and compensates by increas-
ing the voltage output.