TurboChef NGO/SOTA - Page 58

TROUBLESHOOTING
35
Replace the
filament
trans
-
former(s).
Troubleshooting:
F3: MAG CURR (Magnetron Current Low)
Replace K6
r
elay
.
U.S.
Intl.
I
s the K6 mechanical
relay in good working
or
der?
Is the oven International or U.S.?
NO
YES
NO
NO
NO
YES
R
einstall all
parts and
place the
o
ven back in
ser
vice.
YES
R
eplace the
control board.
YES
R
eplace
affected
parts.
Replace the
capacitor(s).
Replace the
high-voltage
diode(s).
R
eplace the
high-v
oltage
trans
-
former(s).
I
s primary voltage present at the
high-voltage transformers (page 24)?
NE
VER TEST SECONDARY
VOLTAGES
NO
Replace the
control board.
NO
YES
I
nspect/replace
wiring betw
een B-17,
C-14 of the control
board and terminals
A+B of the K8 relay.
I
s voltage leaving the K8
anode r
elay on terminals
4+6?
Replace the K8 anode relay.
Are 10+ amps present
during the F3 fault
alarm?
Replace the
magnetron(s).
Inspect/replace wiring between terminal 4 (K8) and
T1-1 (HV transformer), and between terminal 6
(K8) and T2-3 (HV transformer; US 240 VAC) /
T2-2 (HV transformer; US 208
VAC or Intl.).
E
nergiz
e the magnetron
cir
cuit fr
om Test Mode
(page 13) and test for
control voltage on the
K8 anode r
elay. Is 24
VDC pr
esent on
terminals A+B?
Confirm the F3 fuse is a
20-amp A
TMR fuse. I
s it
open/blo
wn?
Replace the F3 fuse and
verify the operation of
the interlock switches
(page 21).
YES
R
un test cook
cy
cles to see if
fault repeats
(page 9). I
f not,
clear faults. Did
fault repeat?
NO
YES
Energize the mag-
netron circuit from
Test Mode (page 13).
Ar
e ther
e 10+ amps
present on the current
transformer wir
e,
located on the contr
ol
boar
d?
YES
Energize the mag-
netron circuit
from Test Mode
(page 13) and test
for control voltage
to the K8 anode
relay. Is 24 VDC
pr
esent on pins B-
17 and C-14 on
the control board?
NO
YES
Remove and inspect the
magnetrons for discolored
antennas or waveguide
contaminants. Were any
defects found?
NO
YES
NO
YES
YES
YES
NO
T
est the high-voltage transformers
(page 24). Are they functioning
properly?
NO
Test the filament transformers
(page 24). Are they functioning
properly?
NO
T
est the capacitors (page 23).
Ar
e they functioning pr
operly?
NO
YES
T
est the high-voltage
diodes (page 25). Ar
e
they functioning
properly?