Speed Adjustment

This is a 0 to 10 K ohm, 1 turn potentiometer. With

 

Potentiometer

power off, remove the black and white pot leads

 

 

from the motor control board at terminals P1, P2.

 

 

Place the meter leads on the black lead (P2) and

 

 

on the white lead (P1). Rotating the pot., slowly,

 

 

from low to high, the meter reading should show an

 

 

even transition from 0 to 10 K 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.

 

DC Motor Control Board

Check for 208/240 VAC input to the control board at

 

 

terminals L1 and L2. If not present, check wiring

 

 

back to the oven fan switch. If voltage is present at

 

 

L1 and L2, check both fuses on control board (8A

 

 

line and 1A armature), check the VDC output at

 

 

terminals A+ and A-. If voltage is present at

 

 

terminals L1 and L2, and DC voltage is present at

 

 

A+ and A-, but motor does not run, check gear

 

 

motor as follows.

 

Conveyor Gear Motor

If DC voltage is present at A+ and A- and the motor

 

 

does not run, first check the mini breaker and then

 

 

the conveyor. Refer to the next possible cause.

 

 

Check the leads to the motor for evidence of any

 

 

shorts or opens, and each lead to ground. Check

 

 

motor brushes. From the top of the motor, rotate

 

 

motor shaft to determine if there is a locked rotor or

 

 

a locked gear box (use care so magnet and H.S.

 

 

board are not damaged). Replace motor as

 

 

needed.

 

Conveyor

Check for any mechanical misalignment. Also

 

 

check for worn bearings. A conveyor belt that is

 

 

over tightened will cause excessive bearing wear

 

 

and sometimes, irregular speed.

Conveyor speed varying or

Power Supply

Check power supply at the DC control board for the

intermittent

 

208/240 VAC at board terminals L1 and L2.

 

Motor Control Board

Place the test meter probes on terminals A+ and A-.

 

 

(With speed potentiometer set to maximum speed

 

 

(Approximately 2 minutes), the meter reading

 

 

should be approximately 100 VDC (± 3%), if voltage

 

 

is not steady within limits, then the board is

 

 

probably bad. Always check the speed pot. Be

 

 

sure it is okay before changing a board. This test is

 

 

not always 100% accurate as this test is not

 

 

performed at operating speeds. However, this test

 

 

is the best method currently available.

 

DC Gearmotor

If the DC control board is steady, then the problem

 

 

may be the motor or gearbox. Check the brushes

 

 

in the motor for excessive arching and/or unusual

 

 

wear. Check the motor and gearbox from

 

 

instruction located on page 14 under "possible

 

 

cause" listing "conveyor gear motor."

 

Magnet

Check to insure that the magnet (cemented to shaft

 

 

of conveyor drive motor) has not been damaged, or

 

 

come loose from motor shaft. Replace as needed.

Impinger II –Advantage Service Manual - Domestic

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Lincoln II - Advantage Series service manual