MT2136 SERIES CONVEYOR OVEN SERVICE AND REPAIR MANUAL BLODGETT OVEN COMPANY www.blodgettcorp.com 50 Lakeside Avenue, Box 586, Burlington, Vermont 05402 USA Telephone (802) 658Ć6600 Fax: (802)864Ć0183 PN M9884 A (6/01) 1999 - G.S. Blodgett Corporation All rights reserved. Duplication of the information in this manual is prohibited without the consent of the Blodgett Service Department.
TABLE OF CONTENTS 1. INTRODUCTION Oven Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ventilation Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gas Specifications . . . . . . . . . . . . . . . . . . . .
TABLE OF CONTENTS 4. CALIBRATION AND ADJUSTMENT Convection Blower Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Regulated Gas Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard Controller Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Belt Speed Calibration - Open Loop . . . . . . . .
CHAPTER 1 INTRODUCTION
MT2136 OVEN SPECIFICATIONS VENTILATION REQUIREMENTS ELECTRICAL SPECIFICATIONS The hood should completely cover the unit with an overhang of at least 6" (15 cm) on all sides not adjaĆ cent to a wall. The distance from the floor to the lower edge of the hood should not exceed 7' (2.1 m). The ventilation system should replace 80% of the exhaust volume with fresh make up air. TABLE 1 should be used as a guideline. NOTE: Three Phase hookup is not permitted on gas models.
INTRODUCTION Installations outside the U.S. CE approved installations MT2136G ovens require a 15 amp, 50HZ, 1F, 220Ć240VAC, 3 wire service consisting of L1, neuĆ tral and ground. See FIGURE 2. Use 90 C wire and size to National Electric or local codes. The MT2136G requires a 15 amp 50Hz, 1F, 230 VAC, 3 wire service consisting of L1, neutral and ground. Connect exhaust fan connector 1 and 2. See FIGURE 2. Use 90 C wire and size according to local codes.
MT2136 GAS SPECIFICATIONS GAS CONNECTIONS GAS REQUIREMENTS Domestic and General Export installations The firing rate for the MT2136G is 55,000 BTU/Hr. (16 kW/Hr.) The gas line should be large enough to accommoĆ date the peak demand of all the gas appliances. TABLE 2 reflects a straight line, 50 foot run with no coupling restrictions and no other appliances drawing service. Gas line installations MUST conĆ form to National Fuel Gas Code NFPA 54/ANSI Z223.1 Sec. 1.4 (Latest Edition).
INTRODUCTION ILLUSTRATED PARTS LISTS CONVEYOR COMPONENTS NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. 39 Ref. Part No. No. Description Description M2740 Belt, Wire S/S 21" SB (Per Foot) (Total 11 FT) 21169 Knob, Speed Control PotentiomĆ eter M6336 Belt, Wire S/S 10" TB (Per Foot) (Total 21 FT) M2378 Motor, Conveyor Drive, Bodine 130V Tensioner Assy.
MT2136 TEMPERATURE CONTROLS Computer solid state controls for ovens manufactured after mid sept., 1993 NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. Ref. Part No. No. Description Description M3149 Controller, Digital Temperature M3314 Bracket, Computer Wall M3439 Relay, Digital Temp. Controller, 10 AMP, 250V M5661 Bracket Assy.
INTRODUCTION GAS BURNER COMPONENTS NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. Ref. Part No. No. Description 20287 Valve, Single Solenoid 110/120V M0282 Valve, Manual Gas 16 M1054 Spark Box, 24V 3 M0767 Blower Motor, Combustion w/ Control Box 11 M5495 Dual Solenoid/Pressure RegulaĆ tor, Nat.
MT2136 ELECTRICAL COMPONENTS NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. Ref. Part No. No. Description M2571 Element Assy., 208V, 3 PH, 15 KW (Qty 1) M2697 Element Assy., 208V, 1 PH, 15 KW (Qty 1) M2572 Element Assy., 240V, 3 PH, 15 KW (Qty 1) M2698 Element Assy.
INTRODUCTION EXTERIOR COMPONENTS NOTE: = ASAP Distributor Required Stocking Parts = Doors Are Not Returnable Ref. Part No. No. Ref. Part No. No.
MT2136 EXCLUSIVE TO VERSION AB Serial number model identification code of BK=MT2136G or FB=MT2136E. NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. Description 1 M5070 Conveyor Assy., Drive Side SB M7001 False Front w/ Door M5066 Conveyor Assy., Idle Side SB M6213 M5069 Conveyor Assy., Drive Side TB Access Panel, Combustion Compartment M5067 Conveyor Assy., Idle Side TB M6044 Ref. Part No. No. M6035 Snap Disc, L110Ć20F, 3 Pole M5302 Nozzle Assy.
INTRODUCTION EXCLUSIVE TO EXPORT 50 HZ (ZA VERSION) NOTE: = ASAP Distributor Required Stocking Parts Ref. Part No. No. Ref. Part No. No. Description M2246 Burner Assy., Complete M2386 Blower Motor, Combustion M2384 Transformer (Burner Assy.) M2245 Valve, Single Solenoid, 240VAC M2573 Element Assy., 220/380V, 3 PH, 15 KW M2699 Description M7880 Computer Control Kit, Closed Loop SB (CE) M3237 Burner Assy. (CE) 16 M7334 Pilot Burner & Igniter Assy.
MT2136 EXTERIOR COMPONENTS 35 30 29 39 35 28 38 33 26 36 27 37 31 FIGURE 3 1-11 34 32
INTRODUCTION DOMESTIC GAS BURNER COMPONENTS (Control Box not Shown) 1 2 13 3 5 13 4 13 12 11 14 15 7 8 9 6 10 FIGURE 4 1-12
MT2136 CE GAS BURNER COMPONENTS (Control Box not Shown) 16 17 FIGURE 5 1-13
INTRODUCTION CONTROL PLATE ASSEMBLY 22 18 23 24 25 20 16 19 21 EXCLUSIVE TO CE 26 40 41 42 FIGURE 6 1-14 43
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CHAPTER 2 ASSEMBLY
MT2136 OVEN ASSEMBLY PROCEDURES NOZZLES WIRE CONVEYOR BELT 1. Install the nozzles from the center of the oven working toward the ends. Make sure the top tongue of each nozzle fits into the upper recĆ tangular cutĆout in the nozzle support plate at the top rear of the oven. NOTE: The conveyor belt has loops on both sides. The belt must be installed so the loops travĆ el as shown in FIGURE 1. 1. Thread the wire belt from the right side of the oven, lower level first. 2.
ASSEMBLY CONVEYOR BELT TENSIONERS Unless otherwise specified, the conveyor travel is factory set for leftĆtoĆright operation when facing the front of the oven. If a direction change is reĆ quired, the polarity of the drive motor must be reĆ versed. To change the polarity of the drive motor, disconnect the oven from the power source and inĆ terchange the black and white motor leads at the D.C. Controller Board located within the control box.
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CHAPTER 3 OPERATION
MT2136 STANDARD CONTROL OPTIONS U.E. TEMPERATURE CONTROLLER WITH OPEN LOOP DC DRIVE SYSTEM 1 2 3 4 5 ON 6 OFF HEAT ON OFF BLOWER COOK TIME ON OFF 7 TEMPERATURE CONVEYOR FIGURE 1 CONTROL DESCRIPTION SWITCH (5) to OFF and wait 5 minutes before turning back to ON. 1. COOK TIME DISPLAY - Gives the belt speed. 2. CONVEYOR ADJUSTMENT KNOB - Turn to adjust the conveyor speed. 3. TEMPERATURE CONTROL KNOB - Turn to set cook temperature. 4. HEAT LIGHT - Indicates the control is calling for heat.
OPERATION ATHENA TEMPERATURE CONTROLLER WITH OPEN LOOP DC DRIVE SYSTEM 1 2 3 4 5 6 7 8 ON 9 OFF HEAT COOK TIME ON OFF 10 ACTUAL SETPOINT ON OFF BLOWER HEAT TEMPERATURE CONVEYOR FIGURE 2 CONTROL DESCRIPTION NOTE: If the oven fails to ignite after the thirty (30) second purge, turn the blower switch OFF and wait 5 minutes before turning back ON. 1. COOK TIME DISPLAY - Gives the belt speed. 2. CONVEYOR ADJUSTMENT KNOB - Turn to adjust the conveyor speed. 3.
MT2136 COMPUTER CONTROLLER 1 2 9 3 8 7 6 5 4 FIGURE 3 CONTROL DESCRIPTION CONTROL OPERATION 1. DIGITAL DISPLAY - Displays the time, temĆ perature and controller related information. To turn the oven on: 1. Press and hold the ON/OFF key (2). The disĆ play reads OFF when the oven is idle. 2. The display flashes WAIT LOW SET TIME. 3. The FAN and HEAT status lamps (9) light. The fans begin to run. The heat rises to the proĆ grammed temperature. The conveyor belt travels at the programmed speed.
OPERATION PROGRAMMING PROCEDURES DISPLAY INFORMATION Programming the Cook Time: WAIT LOW - indicates that the present oven temperature is lower than the set point temperĆ ature. When the oven reaches the set point temperature the display changes to READY. READY - indicates that the oven is ready to acĆ cept product. SET TEMP mmss - indicates the current cook time setting. HIGH TIME - indicates that the temperature is well above the set point.
MT2136 SEQUENCE OF OPERATION NOTE: The following instructions represent the most common configurations. For questions regarding othĆ er options call the Blodgett Service Department at (800)331Ć5842. MT2136E DOMESTIC WITH ATHENA CONTROLS - M2190 REV H COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 4 page 3-25 for compoĆ nent locations. 1. Turn the blower switch (1) to ON. The N.O. conĆ tacts close, the N.C. contacts open.
OPERATION 3. When power is applied to the coils of the motor contactor (4) the contacts close sending powĆ er to the two convection fans (5) located in the back of the oven. 5. The conveyor is driven by an open loop D.C. control system consisting of a conveyor switch (15), time display (16), 10kW potentiometer (17), D.C. speed control board (18), 130 VDC motor (19) and #10 Hall effect pickup (20). AfĆ ter the conveyor switch is turned on, the time display illuminates. The D.C. control board powers up.
MT2136 MT2136E GENERAL EXPORT WITH ATHENA CONTROLS - M2341 REV F COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 5 page 3-26 for compoĆ nent locations. 1. Turn the blower switch (1) to ON. The N.O. conĆ tacts close, the N.C. contacts open. 115 VAC runs to terminal #7 of the hi/lo board (2), L1 of the temperature controller (3) and the coil of the motor contactor (4). Terminal #7 is an outĆ put.
OPERATION er to the two convection fans (5) located in the back of the oven. 5. The conveyor is driven by an open loop D.C. control system consisting of a conveyor switch (15), time display (16), 10kW potentiometer (17), D.C. speed control board (18), 180 VDC motor (19) and #10 Hall effect pickup (20). AfĆ ter the conveyor switch is turned on, the time display illuminates. The D.C. control board powers up.
MT2136 MT2136G AUSTRALIAN UNIT WITH ATHENA CONTROL - M2847 REV C COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 6 page 3-27 for compoĆ nent locations. 1. Turn the blower switch (1) to ON. The N.O. conĆ tacts close, the N.C. contacts open. 115 VAC runs to terminal #7 of the hi/lo board (2), L1 of the temperature controller (3) and the coil of the motor contactor (4). Terminal #7 is an outĆ put.
OPERATION temperature passing its face exceeds the ratĆ ing on the back of the switch. If this switch is cold it should be closed sending power to the common terminal of a differential pressure switch (16). The pressure switch is made between common and N.C. when the combustion motor (10) is idle. When the comĆ bustion motor reaches full speed the differenĆ tial pressure switch toggles from common and N.C. to common and N.O. sending power to the single solenoid gas valve (17). 5.
MT2136 MT2136G CE WITH ATHENA CONTROL - M3163 REV C COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 7 page 3-28 for compoĆ nent locations. 1. Turn the blower switch (1) to ON. The N.O. conĆ tacts close, the N.C. contacts open. 220 or 240 VAC runs to terminal L1 of the temperature controller (2), the coil of the motor contactor (3) and terminals #2 and #7 of the hi/lo limit board (4). Terminal #7 is an output.
OPERATION er times out, power goes to the coil of a SPST relay (13), allowing its contacts to close. switch (22) closes due to high ambient heat. The switch toggles if the temperature passing its face exceeds the rating on the back of the switch. 4. On a call for heat from the temperature controlĆ ler (2), as sensed by the thermocouples, a set of contacts closes sending power out of the N.O. terminal of the temperature controller to one side of a N.C. SPST thermal switch (14).
MT2136 MT2136G DOMESTIC WITH REMOTE COMPUTER CONTROL - M3476 REV B COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 8 page 3-29 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (1). The belt stop relay (2), blower relay (3) and the heat relay (4) energize powering up the oven. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.
OPERATION with an ohm meter. The SPST thermal switch is located in the rear of the conĆ vection fan compartment. 5. The conveyor is driven by an open loop DC control system consisting of a DC speed conĆ trol board (5), a 130 VDC motor (21) and the DAC located in the cooking computer (1). If a time is programmed into the cooking computĆ er, a voltage ranging between .47 and 4.7 is apĆ plied to the DC speed control board.
MT2136 MT2136G DOMESTIC WITH OPEN LOOP COMPUTER CONTROL - M3717 REV B COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 9 page 3-30 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (1). The belt stop relay (2), blower relay (3) and the heat relay (4) energize powering up the oven. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.
OPERATION 4. On a call for heat from the cooking computer (1), as sensed by an RTD probe (18), the heat relay (4) closes sending 115 VAC to one termiĆ nal of a N.C. SPST thermal switch (19). The switch toggles if the temperature passing its face exceeds the rating on the back of the switch. If the switch is closed, 115 VAC is delivĆ ered to the burner control valve (20). This valve opens sending gas to the flame blower (21) for ignition. NOTE: The RTD probe is located in front of the combustion motor.
MT2136 MT2136G DOMESTIC WITH CLOSED LOOP COMPUTER CONTROL - M7287 REV A COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 10 page 3-31 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (1). The belt stop relay (2), blower relay (3) and the heat relay (4) energize powering up the oven. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.
OPERATION closes when there is a 10Ć205 drop in temperature across the face of the switch. 4. On a call for heat from the cooking computer (1), as sensed by an RTD probe (18), the heat relay (4) closes sending 24 VAC to the burner control valve (13). This valve opens sending gas to the flame blower for ignition. NOTE: The RTD probe is located in front of the combustion motor. It should be checked with an ohm meter. 6.
MT2136 MT2136E CE WITH CLOSED LOOP COMPUTER CONTROL - M6476 REV B COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 11 page 3-32 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (1). The belt stop relay (2), blower relay (3) and the heat relay (4) energize powering up the oven. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.
OPERATION 4. The conveyor belt is driven by a closed loop D.C. drive system consisting of a 130 VDC moĆ tor (15), a #2 Hall effect pickup (16), a DC speed control board (17) and the DAC located in the cooking computer. The motor speed varĆ ies based on the time programmed into the cooking computer. If time is programmed, a voltage from .3 to 3.8 is applied to the DC speed control board.
MT2136 MT2136G CE WITH COMPUTER CONTROL - M7290 REV E COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 12 page 3-33 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (19). The blowĆ er relay (1), belt stop relay (6) and heat relay (9) pull in and power up three separate circuits. The voltage to the relay coils is 12 VDC. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25.
OPERATION 8. Power flows from terminal #8 of the triple pole double throw relay (12) to a ten second purge timer (13). This timer allows the combustion blower (15) to operate for ten seconds allowing the combustion chamber to clear of any comĆ bustible gasses. 9. After the timer times out the voltage is applied to the other side of the coil of the single pole single throw relay (11). When that set of conĆ tacts closes, voltage goes to terminal #1 of the Landis & Gyr ignition control system (16).
MT2136 MT2136G GENERAL EXPORT - M7295 REV B COMPONENT REFERENCE OPERATION NOTE: Refer to FIGURE 13 page 3-34 for compoĆ nent locations. 1. Apply power to the oven. Program the time and temperature into the computer (1). The blower relay (2), belt stop relay (3) and heat relay (4) pull in and power up three separate circuits. The voltage to the relay coils is 12 VDC. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.
OPERATION 6. On a call for heat from the cooking computer (1), as sensed by an RTD probe (18), the heat relay (4) closes sending 24 VAC to the main burner valve (17). This valve opens sending gas to the flame blower (13) for ignition. NOTE: The RTD probe is located in front of the combustion motor. It should be checked with an ohm meter. 7. The conveyor belt is driven by a closed loop D.C.
20 19 17 13 21 16 18 13 12 13 15 3 7 4 14 2 1 8 10 9 5 5 6 11 MT2136 FIGURE 4 3-25
20 19 13 17 FIGURE 5 3-26 13 12 16 18 13 15 3 4 7 1 2 14 5 8 10 5 9 6 11 OPERATION
FIGURE 6 3-27 26 18 25 23 18 22 24 19 18 21 3 1 4 2 7 20 5 11 14 15 5 12 13 16 17 8 6 9 10 MT2136
FIGURE 7 3-28 21 29 28 26 21 21 25 27 22 24 2 23 1 7 4 3 20 16 17 19 14 5 18 15 8 5 10 9 13 6 12 11 OPERATION
16 1 16 16 17 3 15 21 5 13 2 4 10 18 19 14 11 12 14 9 6 20 7 8 MT2136 FIGURE 8 3-29
1 FIGURE 9 3-30 16 16 16 16 18 15 3 17 22 5 13 2 4 10 19 20 14 11 12 14 9 6 21 7 8 OPERATION
FIGURE 10 3-31 21 21 21 1 17 22 18 3 16 20 19 5 2 4 14 11 6 12 13 7 15 10 8 9 MT2136
1 FIGURE 11 3-32 8 8 8 8 6 3 7 16 15 17 2 4 18 5 11 9 12 9 13 14 OPERATION
FIGURE 12 3-33 25 25 19 25 22 21 20 1 24 7 6 17 16 9 2 8 3 18 4 10 5 15 11 14 13 12 MT2136
1 OPERATION FIGURE 13 3-34
MT2136 OVEN ADJUSTMENTS FOR COOKING The combination of belt time, oven temperature, and air flow are important for achieving quality reĆ sults from your Blodgett conveyor oven. Use the following guidelines to adjust the belt time and oven temperature of your unit. For questions reĆ garding further oven adjustments, please contact your local Blodgett Sales Representative for assisĆ tance. Air flow adjustments may be necessary to fine tune the oven for your particular product.
CHAPTER 4 CALIBRATION AND ADJUSTMENT
MT2136 CONVECTION BLOWER MOTORS TO CHECK MOTOR ROTATION TO CHECK LOWĆLIMIT 1. Remove the back of the oven body and verify proper motor rotation. (See FIGURE 1) 1. Turn the oven on and let it heat up to approxiĆ mately 200 F (93 C). For motor placement, the direction of rotation is viewed left to right from the oven's rear. Typically the motor direction is referenced to the end of the shaft (EOS).
CALIBRATION AND ADJUSTMENT REGULATED GAS PRESSURE 1. Let the oven run up to 510 F (266 C). You may now verify the operational and regulated gas pressures. If pressure adjustments are needed, turn the adĆ justing screw located under a screw cap of the dual regulated valve. Adjust the gas pressure by turning the screw clockwise to raise the gas pressure and counterĆclockwise to lower the gas pressure. Be sure to reinstall the screw cap; should the diaĆ phragm rupture this cap acts as a flow limiter.
MT2136 STANDARD CONTROLLER CONFIGURATION BELT SPEED CALIBRATION - OPEN LOOP NOTE: The following procedures must be perĆ formed after dc voltage levels have been set and are known to be accurate. Set The Belt Speed DIP Switches. Belt speed DIP switch settings are specified by the following equations: The cooking time digital display should be adĆ justed when changing any of the system compoĆ nents. Prior to adjusting the display, determine the following two specifications: 1.
CALIBRATION AND ADJUSTMENT TEMPERATURE CALIBRATION - UNITED ELECTRIC CONTROLLER NOTE: Th U.E. and Zytron boards get input from eiĆ ther single or dual lead thermocouples. lowers the display reading and raises the temĆ perature. A counterĆclockwise rotation raises the reading and decreases the temperature. Check the oven set point. Adjustment of the potentiometer may affect this reading. Bring the oven up to 525 F (274 C). Verify the caliĆ bration. LOW LIMIT ADJUSTMENT 1. Bring the oven to 200 F (93 C). 2.
MT2136 TEMPERATURE CALIBRATION - ATHENA CONTROLLER THE CONFIGURATION MENUS Setting the Deviation Band Alarm 1. Press and hold the actual temperature key for approximately 10 seconds. When the menu system has been accessed, the display toggles between and either or . The deviation band alarm causes the display to flash when the actual temperature varies (in either direction) from the setpoint. The deviation band alarm is adjustable to off or values from 1 F to 252 F (1 C to 740 C).
CALIBRATION AND ADJUSTMENT LOW LIMIT ADJUSTMENT HIGH LIMIT ADJUSTMENT 1. Bring the oven to 200 F (93 C). NOTE: Refer to the wiring diagram located on the oven or on page 3-25 of the Operation section. For additional assistance call the Blodgett Service department. 2. Turn both the blower and the heat switches to OFF. The blower should continue to run. 3. Monitor the digital temperature control display. The blower motors should shut off within the range of 170Ć135 Fāā(77Ć57 C). 1.
MT2136 COMPUTER CONTROLLER CONFIGURATION COMPUTER CONTROLS INITIATING ACCESS MODE CONFIGURATION The Cooking Computer provides a special Access Mode for setting and displaying certain computer special functions. To initiate the Access Mode place the control in the OFF state, (OFF is shown in the display when power is first applied to the control). Press the following sequence of keys to set the control to Access Mode: CLEAR 1 2 3 4 5 6 ENTER. The display reads ACCESS.
CALIBRATION AND ADJUSTMENT Boost Option - (versions 2.00 or 3.00) When the controller is in the ACCESS" mode, press the following buttons: CLEAR 2 1 2 ENTER to enter the boost option. DISPLAY BOOST / MODEĆ? (Flash alternately) ACTION TAKEN Press PROG ENTER DISPLAY OPTĆ1 OPTĆ2 ACTION TAKEN or Press any numeric key to toggle between OPTĆ1 and OPTĆ2 Select OPTĆ1 to turn off boost mode.
MT2136 TEMPERATURE CALIBRATION TO ENTER THE CALIBRATION MODE 1. Press PROG/ENTER followed by ACT_TEMP. The display flashes either POS * OFFSET or NEG * OFFSET 1. Press the ON/OFF key until OFF is displayed. 2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the access mode. The display reads ACCESS. NOTE: POS OFFSET is displayed if a value has been programmed in for a positive offĆ set. NEG OFFSET is displayed if a valĆ ue has been programmed for a negaĆ tive offset.
CALIBRATION AND ADJUSTMENT BELT SPEED CALIBRATION CLOSED LOOP SYSTEM To enter the calibration mode: 1. Press the ON/OFF key until OFF is displayed. 2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the Access mode. The display reads ACCESS. 3. Press CLEAR TIME TIME TIME ENTER to acĆ cess the Belt Speed Calibration mode. The disĆ play flashes INIT. Belt speed calibration: 1. OVEN LENGTH - Set the length of the conveyĆ or belt to 36. 4.
MT2136 OPEN LOOP SYSTEM - SINGLE BELT To enter the calibration mode: The belt will travel very slowly during this part of the calibration procedure. To minimize the time spent on STEP-2, measure off 10" on the conveyor support. Place an object on the belt and note the travel time for the 10" measured distance. 1. Press the ON/OFF key until OFF is displayed. 2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the Access mode. The display reads ACCESS. 3.
CALIBRATION AND ADJUSTMENT OPEN LOOP SYSTEM - TWIN BELT To enter the calibration mode: 1. Press the ON/OFF key until OFF is displayed. 2. Press CLEAR 1 2 3 4 5 6 PROG/ENTER. The display flashes ACCESS. 3. The display reads STEP-2. The controller is in Step 2 of the calibration procedure: minimum belt speed. The motor control is automatically set to its minimum output. The belt will travel very slowly during this part of the calibration procedure.
MT2136 MOTOR CONTROL BOARD ADJUSTMENT High/low speed motor control board adjustĆ ment for 180 and 130 volt DC motors NOTE: The motor control board is located on the slide out control panel. High Speed Motor Adjustment: For closed loop systems follow Belt Speed VerificaĆ tion through STEP 5 (see page 4-10). For open loop systems follow Belt Speed Calibration through STEP 2 (see page 4-11 or 4-12). 1.
CALIBRATION AND ADJUSTMENT Minimum Speed Torque (current) limiting adjustment (DO NOT ADJUST) Maximum Speed Acceleration Adjustment Switches 2,4,5,6,7 ACC Yellow or Violet (pin 12) Orange or Gray (pin 10) Line Fuse ON DIP Switch on early models only TP2 Socket J1 Blue Gray TORQ MIN TP1 Test Points Blue (pin 8) Violet MAX REG Regulation Adjustment Armature Fuse FL TB1 Speed Pot L N A1 NOTE: Colors may vary between early ovens.
MT2136 RERATING THE APPLIANCE Due to the lack of oxygen at higher elevations, the unit may need to be rerated. (The orifice size may need to be adjusted to accommodate different air pressures at higher elevations.) If not rerated, inĆ complete combustion may occur releasing AldeĆ hydes and CO or Carbon Monoxide. Any of these are unacceptable and may be hazardous to the health of the operator. To choose the correct orifice for different altitudes several factors must be known: 1.
CALIBRATION AND ADJUSTMENT CHECKING THE FIRING RATE Locate the time observed in STEP 2. Move across the table to either the 1/2 cu. ft. or the 2 cu. ft. column to find the gas input to the burner. Method #1 1. Turn off all other appliances on the line. Turn on the appliance to be measured. 2. Using either the 1/2 cu. ft. or the 2 cu. ft. dials located on the gas meter, note the time it takes the indicator to complete one revolution. See FIGURE 9. 2 3 3.
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CHAPTER 5 TROUBLESHOOTING
MT2136 DC DRIVE SYSTEM POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #1 - Belt does not move (standard controls) Conveyor switch is turned off. Turn switch to on. Armature fuse on Bodine board is blown. Ohm this fuse out to determine if blown. If necesĆ sary, replace with 250 milliamp fuse. Determine the amp draw of the motor. Line fuse on Bodine board is blown. Replace with 5 amp fuse. DC motor is leaking oil. Replace motor. Motor ohms out higher then 162W.
TROUBLESHOOTING POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #3 - Computer error code MOTOR Ć SPEED Ć ERROR Belt speed needs calibration. See Calibration and Adjustments. Voltage from Bodine controller to DAC not presĆ ent. The DAC (Digital Analog Control) is a nonĆreĆ pairable component of the computer. There should be approximately 20 VDC between the red and green wires on the 3 pin connection of the DC drive board. Replace the drive motor controller.
MT2136 CONVECTION SYSTEM POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #1 - Blower motor(s) not running Blower switch off. Turn switch to on position. No power to the oven. Verify power to the oven. If there is no power deĆ termine cause. Motor fuse blown. Replace fuse. Determine the amp draw. Faulty start capacitor. Replace capacitor. Motor burned out. Check draw (3 amps or greater). Thermal overload tripped.
TROUBLESHOOTING HEATING SYSTEM POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #1 - Burner will not fire (standard controls) Oven in off mode. Turn the oven on. No power to the oven. Determine if the circuit breaker is tripped. Fuse blown on the control panel. Replace the fuse. Determine if the controller setpoint is above actuĆ al. If the setpoint is not above the actual, reset acĆ cordingly. Intermittent Ignition Device (IID) system locked out.
MT2136 POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #1 - Burner will not fire (computer controls) Oven in OFF mode. Turn to ON position. Emergency stop switch on OFF. Pull switch out to ON. Control circuit breaker tripped. Reset breaker. Combustion motor not running. Check transformer for primary and secondary voltage. Check main control and burner valve relays to see if closed. Check relay in combustion burner box. If bad reĆ place relay.
TROUBLESHOOTING COMPUTER CONTROL SYSTEM POSSIBLE CAUSE(S) SUGGESTED REMEDY Symptom #1 - Computer controller displays: PROBE Ć OPEN Ć PROBE Ć SHORT and alarm buzzer sounds Internal problem with computer controller. Verify display integ. in the 2nd level programĆ ming. If the controller has been programmed the computer may need to be replaced. Loose connections at computer controller. Tighten connections. Shorted or open RTD probe.
MT2136 Symptom #4 - Burner operates sporadically Air pressure switch may be open. Check convection blower (or 4 convection fans) for proper operation. Thermal switch tripped. Determine the ambient temperature in the conĆ trol compartment. If above 140 F (60 C) check the cooling fan operation. Faulty RTD probe. Use the chart in the Technical Appendix (page 6-4) to determine if probe is bad. Replace if necĆ essary. Excessive food/debris accumulation blocking the airflow.
CHAPTER 6 TECHNICAL APPENDIX
MT2136 INTERMITTENT IGNITION SYSTEM PRINCIPLES OF OPERATION In the IID system the probes exposed to the pilot flame are the Flame Sensor and the Pilot Burner Hood. Since the surface area of the pilot hood is larger than the flame sensor, the current rectificaĆ tion process takes place. Current is conducted from terminal 4 at the control through the flame sensor cable to the flame sensor.
TECHNICAL APPENDIX SERVICE PROCEDURES To Measure DC Flame Sensing Current: Service the IID system as follows: 1. Turn off the power supply to the ignition conĆ trol. 1. Make certain the thermostat contacts are open. 2. Disconnect the flame sensor cable from termiĆ nal #4 on Johnson units or terminal #15 on Landis & Gyr units. 2. Check for proper supply voltage at primary and secondary of system transformer. 3. Set the selector switch on the meter to microĆ amp scale.
MT2136 5. Install the Y75 sensing probe into the pilot burner. Reconnect the sensing probe cable. The connections to the sensing probe and control terminal must be secure. REPAIRING THE ELECTRONIC IGNITION SYSTEM Flame Sensing Current Maintenance: The flame sensor is made of carbon steel and subĆ ject to contamination and oxidation buildup. Any buildup on the sensor can add enough resistance to drop the signal below the required minimum. Carbon and oxidation can also build up on the pilot hood.
TECHNICAL APPENDIX COOKING COMPUTER - TEMPERATURE VS RESISTANCE T/F Res/Ohms T/F Res/Ohms T/F Res/Ohms T/F Res/Ohms 70 541.12 230 711.43 390 877.15 550 1038.293 75 546.51 235 716.68 395 882.26 555 1043.255 80 551.9 240 721.92 400 887.36 560 1048.212 85 557.28 245 727.16 405 892.46 565 1053.165 90 562.66 250 732.4 410 897.55 570 1058.113 95 568.04 255 737.63 415 902.63 575 1063.057 100 573.4 260 742.85 420 907.72 580 1067.997 105 578.
MT2136 THERMOELECTRIC VOLTAGE IN ABSOLUTER MILLIVOLTS TYPE J THERMOCOUPLE F Reading +5 F F Reading +5 F 10 -0.611 -0.473 360 9.790 9.944 20 -0.334 -0.195 370 10.098 10.252 30 -0.056 0.084 380 10.407 10.561 40 0.224 0.365 390 10.715 10.869 50 0.507 0.648 400 11.023 11.177 60 0.791 0.933 410 11.332 11.486 70 1.076 1.220 420 11.640 11.794 80 1.363 1.507 430 11.949 12.103 90 1.652 1.797 440 12.257 12.411 100 1.942 2.088 450 12.566 12.
TECHNICAL APPENDIX CONVERSION FACTORS COMMON CONVERSION FACTORS PRESSURE CONVERSIONS FACTORS Multiply By To Get Multiply By To Get BTU/hr .001054804 MJ/hr in/H2O 0.0361 P.S.I. .0002931 kW 25.41 mm/H2O .29285 W 1.868 mm/Hg .0372589 MJ/m3 .0025 kg/cm 2 8.905102 kcal/m 3 .0025 bar MJ/hr 948.0434279 BTU/hr 2.489 mbar Mj/m 3 26,839225 BTU/ft 3 248.9 Pa kW 3414.71732 BTU/hr .2489 kPa ft3 .02832 m3 27.71 in. H2O ft2 .09290304 m2 2.036 in. Hg inches 25.
MT2136 PRESSURE CONVERSION PRESSURE CONVERSION CHART in/H2O P.S.I in/Hg mm/H2O mm/Hg kg/cm2 bar mbar Pa kPa 1 .0361 .0735 25.41 1.868 .0025 .0025 2.489 248.9 .2489 2 .0722 .1470 50.81 3.736 .0051 .0050 4.978 497.8 .4978 3 .1083 .2205 76.22 5.604 .0076 .0075 7.467 746.7 .7467 4 .1444 .2940 101.62 7.472 .0102 .0099 9.956 995.6 .9956 5 .1804 .3673 127.0 9.335 .0127 .0124 12.44 1244 1.244 6 .2165 .4408 152.4 11.203 .0152 .0149 14.93 1493 1.
TECHNICAL APPENDIX in/H2O P.S.I in/Hg mm/H2O mm/Hg 28 1.010 2.056 710.8 52.26 29 1.047 2.132 736.8 30 1.083 2.205 31 1.119 32 kg/cm2 bar mbar Pa kPa .0710 .0696 69.64 6964 6.964 54.18 .0736 .0722 72.19 7219 7.219 762.2 56.04 .0761 .0747 74.67 7467 7.467 2.278 787.5 57.91 .0787 .0772 77.15 7715 7.715 1.155 2.352 812.8 59.77 .0812 .0796 79.63 7963 7.963 33 1.191 2.425 838.2 61.63 .0837 .0821 82.12 8212 8.212 34 1.227 2.498 863.5 63.
