The convection system – TurboChef Technologies 2020 User Manual
Page 42

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O V E N S YS T E M S
Accessing Parameters
WARNING: DO NOT perform this
procedure unless instructed by TurboChef.
Changing the parameters to other than
those preset by TurboChef can damage
critical oven components.
NOTE: “Motor Rated Speed” (07) is RPM of
motor before gearbox, not after.
1. Open the right end bell (page A-8).
2. Locate the CMSC (page A-8).
3. Press the
M
key.
4. Use the and keys to navigate the
parameters. See page 40.
5. Press the
M
key to access the parameter
shown on the CMSC display.
6. Use the and keys to manipulate the
parameter.
7. Press the
M
key to return to the parameter
selection.
8. Repeat steps 4-7 to manipulate other
parameters as needed.
The Convection System
This section contains information about and
testing procedures for the following
components:
- Blower Motor
- Blower Motor Speed Controller (BMSC)
- Heaters
Blower Motor
The convection motor is a brushless AC
switch reluctance type. Its top speed is 7100
RPM at 1 HP. The motor is controlled by a
proprietary controller.
Testing Procedure
1. Disconnect line voltage from the unit.
2. Make sure the motor spins freely.
3. Take a resistance reading of the motor
windings and use Figure 34 to verify the
resistance readings are correct.
4. If the resistance readings are correct,
reconnect motor wiring and then apply
line voltage to the unit and check for
voltage applied to the motor windings.
5. If no voltage is present, ensure the BMSC is
operating properly (see below).
6. If BMSC is operating properly, inspect the
wire harness for damage or shorts (pages
37-38).
7. If wire harness is intact and undamaged and
the BMSC is operating properly, the blower
motor is damaged or defective and must be
replaced (page A-7 = lower, A-8 = upper).
Blower Motor Speed Controller (BMSC)
The motor controller is proprietary and will
only operate the convection motor described
above. The motor controller is controlled on
command from the I/O control board and a
0-10VDC speed command from the I/O
control board. See pages 27-28 for
troubleshooting.
Heaters
The back and front convection heaters are
rated at 6750 watts at 208 VAC with a resist-
ance of 14.4 Ohms. The heaters are controlled
by the K4/K5 solid state relay and can be
tested in
TEST MODE
(see page 17).
To
From
Description
Expected Resistance
Black
Brown
Winding (A-B)
2.3-2.8
W
Black
White
Winding (A-C)
2.3-2.8
W
Red
White
Winding (B-C)
2.3-2.8
W
N/A
Green
Windings to
chassis
Open
Figure 34: Blower Motor Ohm Chart (Motor Windings)