Lincoln 1400 Series ユーザーズマニュアル

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Impinger I – 1400 Series Advantage Service Manual – Dom & Int’l 
19
Temperature Control Board 
Check for 120 VAC input to temperature control 
board. If not present, check wiring from Hi-Limit to 
temperature control board. Turn the temperature 
adjustment dial to the maximum temperature position. 
Check for 120 VAC at coil of mercury contactor(s). 
Next, short the leads of thermocouple on the 
temperature control board, check for 120 VAC at coil 
of mercury contactor(s). If voltage is not present, 
replace temperature control board. If voltage is 
present, proceed. 
Thermocouple Probe 
Remove thermocouple leads from the temperature 
control board, and measure the millivolt output of the 
leads. Refer to chart (page 25) in adjustment section 
for proper millivolt readings. 
Mercury Contactor(s) 
Check for 120 VAC to the contactor coil. If voltage is 
present and contactor will not activate, replace the 
contactor(s). Also check each contactor for proper 
high voltage input and output. 
50 Amp Fuses 
If there is no high voltage input to the mercury 
contactor(s), check the 50 amp fuses and replace if 
necessary. 
Heater Elements 
Check the Amp. draw on each hot leg for proper load. 
Check the specification plate for rating information. If 
the Amp. draw is low or high, check the individual 
elements for opens, shorts, and proper resistance. To 
check resistance of the elements, turn off the power! 
Remove all leads from the elements and use an 
accurate digital VOM. The element resistance should 
be as follows: 208V - 9.8 ohms approx. 220V - 10.5 
ohms approx. 240V - 13 ohms approx. If all readings 
are not correct, replace elements as needed. 
Oven heats with 
switch off 
Mercury Contactor(s) 
The mercury contactor has probably malfunctioned in 
the closed position. If there is no voltage to the 
operating coil, but there is high voltage at the 
contactor output, replace the mercury contactor. 
Voltage Supply (Export Ovens)  Check incoming voltage supply, check breakers and 
reset if required. For some export ovens there is a 
control circuit step down transformer. This transformer 
steps down supply voltage to 120 VAC. If conveyor 
will not run, the secondary of this transformer must be 
checked for 120 VAC output. Check specific oven 
model schematic for circuit location. 
Speed Adjustment 
Potentiometer 
This is a 0 to 10K ohm, 1 turn potentiometer. With 
power off, remove the black and white pot leads from 
the motor control board at terminals P1 and P2 with a 
digital multimeter, check the ohm reading on the black 
lead (P2) and the white lead (P1). Rotating the pot, 
slowly, from low to high, the meter reading should 
show an even transition from 0 to 10K ohms ± 5%. 
There should be no dead or open spots through out 
the 1 turn of the pot. Check both leads to 
ground.There should be no continuity to ground. If any 
of the above checks fail, replace the pot. 
Conveyor will not run 
DC Motor Control Board 
Check for 120 VAC input to the control board at 
terminals L1 and L2.If not present, check back to 
power source if necessary. If 120 VAC is present at 
L1 and L2, check the VDC output at terminals A+ and 
A-. If 120 VAC is present at terminals L1 and L2, but 
DC voltage is not present at A+ and A-, verify fuses 
are not blown, if fuses check ok, replace the board. If 
DC voltage is present at A+ and A-, but motor does 
not run, check gear motor as follows: