Lincoln 1200, 1400 service manual D. C. Motor Control Board, SN 4390 - 14974 1000 SERIES GAS OVENS

D. C. MOTOR CONTROL BOARD

SN 4390 - 14974 1000 SERIES GAS OVENS

SN 4390 - 14790 1200 SERIES

Three different styles of control boards have been used and all three are still usable. All three were supplied under the same part number.

STYLE 1 CONTROL BOARD ADJUSTMENT

NOTE: A digital meter must be used for this adjustment.

Voltage at L1 and L2 terminals of the control board is to be 120 VAC ± 10% Connect a digital volt meter to terminals A+ and A-, set meter on 200 VDC scale. Turn speed control pot. (on oven control panel) to its maximum speed setting.

Turn "MAX", "MIN", and "IR" pots counter clockwise until they stop (DO NOT turn CL pot.) Adjust "TACH" pot. so the volt meter indicates 110 VDC ± 0.5 volts.

Adjust "IR" pot. to read between 1.5 and 2 VDC above tach. reading.

(Example: If tach. reading would be 110.3 then adjust IR to between 111.8 VDC and 112.3 VDC)

Turn speed control pot. to its minimum speed setting.

Adjust "MIN" pot. so the voltmeter indicates between 2 and 6 VDC.

Turn speed control dial to obtain a reading of 22 VDC on your meter. Observe for approximately 30 seconds to see if stable within ± 0.5 VDC. Repeat at 35 VDC.

Check speed of conveyor and adjust time/temp. display if necessary. Seal pots with Glyptol or nail polish.

			L 1			A+
	4 A. FUSE				1 A. FUSE			.
									RESISTOR
				L 2
							A -
		P 2
	P 3		P 1
MAX			MIN		IR CL TACH T 1					T 2

BOARD P/N 369155

STYLE 1

			L 1				A +
									CHOKE
	4 A. FUSE					1 A. FUSE
					L 2
								A -
		P 2
	P 3			P 1
MAX				MIN			IR CL TACH T 1 T 2

" B " BOARD P/N 369272

STYLE 2 AND STYLE 3 CONTROL BOARD ADJUSTMENT

NOTE: A digital meter must be used.

Voltage at L1 and L2 terminals of the control board is to be 120 VAC± 10%. Connect a digital voltmetet to terminal T1 and T2, set the meter on DC scale. Turn speed control pot. (on oven control panel) to its maximum speed setting. Adjust the "MAX" pot. so the voltmeter indicates 22.6 to 22.8 VDC.

Turn the speed control pot. to its minimum speed setting. Adjust the "MIN" pot. so the voltmeter indicates 1.4 to 1.5 VDC.

Reset the speed control pot. to its maximum speed setting and check if voltage is still at 22.6 to 22.8 VDC. Readjust if necessary.

Reset the speed control pot. to its maximum speed setting and check if voltage is still at 1.4 to 1.5 VDC. Readjust if necessary.

If readjustment of either the "MAX" or "MIN" pot. was necessary, the opposite must always be

46 Impinger I -–1000 Series Service Manual - Domestic