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Service Manual for

RCO Speed Oven

Thermal Cutout Replacement

1. Remove the unit from its power source and follow

the proper Lockout/Tagout procedures.

2. Remove the top and right side panels.
3. Tag and disconnect the faulty Thermal Cutout

switch wires.

4. Remove the faulty Thermal Cutout switch.
5. Reverse this procedure to install the new Thermal

Cutout switch.

6. Restore the unit to its power source and check for

proper operation.

7. Remove the unit from its power source and reattach

all covers and panels

8. Restore power to the unit.

HEATING ELEMENTS

Before performing any service that

involves electrical connection or disconnection

and/or exposure to electrical components,

always follow the Electrical LOCKOUT/TAGOUT

Procedure. Disconnect all circuits. Failure to

comply can cause property damage, injury

or death.

Discharge the HV Capacitors.

Refer to the Discharging the High Voltage

System section of the manual for proper
instructions for this procedure.

Heating Elements

Location of Heating Elements

Testing Procedures

Disconnect the wires from the Heating Elements. Test

both elements using an Ohm meter. Each element

should read from 18.14 to 21.01Ω.

Heating Element Replacement

1. Remove the unit from its power source and follow

the proper Lockout/Tagout procedures.

2. Remove the top and side panels.
3. Tag and disconnect the Exhaust Fans and Thermal

Cutout wires.

4.  Remove the rear panels.
5.  Tag and disconnect the Heating Element wires.
6.  Remove the Insulation Panel and Insulation.

Insulation

Panel

Insulation Panel Removed

7. Remove the Diverter Heater Box Assembly.

Diverter Heat Box Assembly

Diverter Heat Assembly Removed

Содержание RCO

Страница 1: ...cing Be sure all necessary tools test equipment and skills are available Those procedures for which you do not have the proper skills and test equipment must be performed only by a qualified Duke trained service technician This manual is Copyright 2011 Duke Manufacturing Co All rights reserved Reproduction without written permission is prohibited Duke is a registered trademark of the Duke Manufact...

Страница 2: ...injury or death Appliances equipped with a flexible electric supply cord are provided with a three prong grounding plug It is imperative that this plug be connected into a properly grounded three prong receptacle Failure to comply with this procedure can cause property damage injury or death If the receptacle is not the proper grounding type contact an electrician Do not remove the grounding prong...

Страница 3: ...other damage 4 Damage to or loosening of hinges and latches 5 Evidence of dropping or abuse C Beforeturningonmicrowavepowerforanyservicetestorinspectionwithinthemicrowavegeneratingcompartments check the magnetron wave guide or transmission line and cavity for proper alignment integrity and connections D Any defective or misadjusted components in the interlock door seal and microwave generation and...

Страница 4: ...ice Panel 9 EXHAUST FANS 9 Exhaust Fan Replacement 10 Left Side Tangential Blower 10 Tangential Blower Replacement 10 Right Side Cooling Fan 11 SOLID STATE RELAYS 11 MONITOR RELAY 12 VOLTAGE RELAY 12 LINE FUSE 13 CONTROL BOX ASSEMBLY 14 SIGNAL TRANSFORMER 15 DOOR SWITCHES 15 THERMAL CUTOUTS 16 HEATING ELEMENTS 17 DOOR REPLACEMENT 18 INVERTER 19 CONVECTION BLOWER MOTOR ASSEMBLIES 19 MAGNETRON COOLI...

Страница 5: ... SYSTEM 33 Function 33 Location and Access 33 Safety Issues 33 Tools Required 33 HIGH VOLTAGE CAPACITOR DISCHARGE PROCEDURE 33 POWER TRANSFORMER TEST 34 HIGH VOLTAGE DIODE TEST 34 MONITOR RELAY 35 Monitor Circuit Test 36 ADJUSTMENTS 38 DOOR INTERLOCK ADJUSTMENT 38 INVERTER PROGRAMMING 39 Programming Procedure 39 Inverter Settings 40 MAINTENANCE 49 STAINLESS STEEL CARE 49 CARE AND CLEANING 49 TROUB...

Страница 6: ...pect oven for physical damage to the cabinet Also check the oven cavity for damage Report any damage to the source of purchase immediately Do not attempt to install or use the oven if damaged Remove all materials from oven interior If oven has been stored in an extremely cold area wait a few hours before connecting power RADIO INTERFERENCE Microwave operation may cause interference to radio televi...

Страница 7: ... Weight Unpacked 250lbs 113kg Packed 325lbs 147kg Clearances Top 6 15 2cm Sides 3 7 62cm when next to other heat sources 5 1 3cm when next to wall Back 0 The plug must be connected to a properly installed and grounded outlet DO NOT change the unit s cord If the cord is too shortanadditionalgroundedoutletmustbeinstalled This oven must be connected to a separate circuit with the electrical rating as...

Страница 8: ...cause property damage injury or death CAUTION Interior components and surfaces may be hot if the unit has been in recent use Top Panel Before performing any service that involves electrical connection or disconnection and or exposure to electrical components always follow the Electrical LOCKOUT TAGOUT Procedure Disconnect all circuits Failure to comply can cause property damage injury or death 1 R...

Страница 9: ... TAGOUT Procedure Disconnect all circuits Failure to comply can cause property damage injury or death Louvered Rear Service Panel Location of Louvered Rear Service Panel Removing the Louvered Rear Service Panel provides access to the High Voltage components 1 Remove the unit from its power source and follow the proper Lockout Tagout procedures 2 Remove the screws securing the Louvered Rear Panel t...

Страница 10: ...rty damage injury or death The Tangential Blower is located on the left side of the oven Tangential Blower Location of Tangential Blower Testing The Left Side Tangential Fan operates constantly when the oven is connected to its power source It provides cooling for the electrical compartment If not operating the line fuse should be checked Inspect all wiring between the fuse holder and the fan Test...

Страница 11: ... screws and nuts that secure the Cooling Fan to the right side panel Retain for use later 5 Remove the Cooling Fan 6 Reverse procedure to install the replacement fan 7 Restore the unit to service and check for proper operation 8 Reattached all panels and covers SOLID STATE RELAYS Before performing any service that involves electrical connection or disconnection and or exposure to electrical compon...

Страница 12: ...Failure of the Mag SSR failure of components in the magnetron system or a combination of failures of the controllerPCB thePrimaryDoorSwitch andtheSecondary Door Switch are sources of Monitor circuit activation and the resultant fuse trip The Monitor Relay output contacts experience excessive current loads when activated preventing future operation of this safety circuit The Monitor Relay must be r...

Страница 13: ... LINE FUSE Before performing any service that involves electrical connection or disconnection and or exposure to electrical components always followtheElectricalLOCKOUT TAGOUTProcedure Disconnect all circuits Failure to comply can cause property damage injury or death The line fuse is a component of the supply circuit for all components including all of the cooling fans It is located in the fuse c...

Страница 14: ...ual for full details on testing Control Board Control Box Replacement 1 Remove the unit from its power source and follow the proper Lockout Tagout procedures 2 Tag and disconnect wires to the Control Board 3 Remove the Control Box Assembly mounting screws Mounting Screws Control Box Assembly Mounting Screws 4 Remove the faulty Control Box Assembly 5 Install the replacement Control Box Assembly 6 R...

Страница 15: ...r Operational Testing With a 208 240 VAC on the Primary winding input the measured voltage across the entire Secondary winding output should be approximately 24 VAC The voltage across either outer terminal and middle terminal should be approximately 12 VAC A short to ground can be measured by testing for continuitybetweeneachindividualterminalandground 1 Remove the unit from its power source and f...

Страница 16: ...Restore power to the unit 10 Perform a Microwave Leakage Test as described on page 32 to validate proper functionality THERMAL CUTOUTS Before performing any service that involves electrical connection or disconnection and or exposure to electrical components always followtheElectricalLOCKOUT TAGOUTProcedure Disconnect all circuits Failure to comply can cause property damage injury or death The The...

Страница 17: ... TAGOUT Procedure Disconnect all circuits Failure to comply can cause property damage injury or death Discharge the HV Capacitors Refer to the Discharging the High Voltage System section of the manual for proper instructions for this procedure Heating Elements Location of Heating Elements Testing Procedures Disconnect the wires from the Heating Elements Test both elements using an Ohm meter Each e...

Страница 18: ...and or exposure to electrical components always followtheElectricalLOCKOUT TAGOUTProcedure Disconnect all circuits Failure to comply can cause property damage injury or death The door assembly should be replaced if the door seal choke or door face plate is damaged A damaged door may cause a potential hazard to the operator The oven must not be used until the door is replaced CAUTION If the oven ha...

Страница 19: ... disconnect the Inverter wires 4 RemovethemountingscrewssecuringtheInverter to the unit and remove the inverter 5 InstallthereplacementInverter Ensuretheinverter is oriented correctly 6 Referring to the tags reconnect all of the wires 7 Refer to Inverter Programming Instructions in this manual to continue CONVECTION BLOWER MOTOR ASSEMBLIES Before performing any service that involves electrical con...

Страница 20: ...L3 Ð E 3 R Orange T1 ORANGE ORANGE YELLOW YELLOW BLUE BLUE T2 T3 L1 L2 L3 L1 L2 L3 Blower Motor Assembly Wiring Diagram 8 Briefly restore power to the unit and ensure the Blower Motor Assembly is operating correctly 9 Removetheunitfromitspowersourceandreattach all covers and panels Note If the right side panel wasremovedreconnectthecoolingfanwiresbefore attaching the top cover 10 Restore the unit ...

Страница 21: ...perty damage injury or death Refer to the Discharging the High Voltage System section of the manual for proper instructions for this procedure Hot Surfaces The Magnetron housings may be hot Magnetron Thermal Switches Location of Magnetron Thermal Switches Operational Testing The Magnetron Thermal Switches are connected in series with high voltage transformer primary circuit and are normally closed...

Страница 22: ... TherightandleftMagcircuitsuseidenticalcomponents and wiring Each Mag circuit has a dedicated 2 4KV secondary supply from the Mag transformer and a high voltage doubling circuit capacitor and diode package to step up to the 4KV microwave power The primaries of the Mag transformers have 208V or 240V taps auto selected by the controller PCB based on sensed line supply voltage to the oven through the...

Страница 23: ...etron mounting nuts and the defective Magnetron Make note of the Magnetron orientation before removing it 8 Install the replacement Magnetron ensuring its orientation matches the one just removed 9 Referring to the tags reconnect the Magnetron wires and the Magnetron Thermal Switch wires 10 Reinstall the Magnetron Blower Assembly 11 Referring to the tags reconnect the fan motor wires 12 Reattached...

Страница 24: ...oil The Monitor circuit disables the oven by tripping the internal 30A Fast Blow Fuse if Mag power is detected with the oven s door open or ajar through the output contacts of the Monitor Relay L1 MAG T1 L1 30A Fuse 208 240 NC NO 2 NC NO 1 230V COIL Secondary Interlock Sw Left Primary Interlock Sw Monitor Relay Tap Relay NO 208 NC 240 Bottom Right Monitor Sw Top Right NO NC NO NC NC NO MAG XFMR PR...

Страница 25: ...7 Removetheunitfromitspowersourceandreattach all panels and covers 18 Restore power to the unit HIGH VOLTAGE HV CAPACITORS Before performing any service that involves electrical connection or disconnection and or exposure to electrical components always followtheElectricalLOCKOUT TAGOUTProcedure Disconnect all circuits Failure to comply can cause property damage injury or death The High Voltage Ca...

Страница 26: ...age Diode HV016 HV015 Chassis GND wire to Xfmr mounting plate at earth safety chassis GND Chassis GND via waveguide weldment Chassis GND Xfmr winding to the Xfmr stack to the Xfmr mounting plate to earth safety chassis GND 0 85F 2500V Magnetron F FA 6B 6A 2K C1 6V SECONDARY 2 4 kV SECONDARY Magnetron Circuit Schematic HV Capacitor Replacement 1 Remove the unit from its power source and follow the ...

Страница 27: ...rlock Switch and Secondary Interlock Switch circuits interact to enable or trigger the Mag SSR only when the oven door is closed and a microwave recipe is selected The Monitor circuit detects failures in the Mag circuits from the output of the Mag SSR to the Monitor Door Switch to the Monitor Relay coil The Monitor circuit disables the oven by tripping the internal 30A Fast Blow Fuse if Mag power ...

Страница 28: ...itor retains a 2 5kV DC charge after the oven has been disconnected from its power source The capacitor must be properly discharged prior to beginning work on any components in the high voltage area Failure to comply can cause property damage injury or death There are two Waveguides one for each Magnetron They are mounted on either side of the unit Waveguides Waveguide Location A Waveguide should ...

Страница 29: ...stall the replacement Waveguide noting how the pins slide into the slotted opening Once installed Waveguide should fit firmly with no movement 15 Attach the Waveguide inside cook cavity first making sure it is centered within the opening 16 Apply silicone gasket on the surface to which the Mounting Brackets fasten 17 Install NEW Waveguide Mounting Brackets Do not fully tighten the screws until all...

Страница 30: ...ron error This error will only occur if one of the magnetronsisinactive Ifbothofthemareinactive then it will be a Door Ajar error If this screen is displayed themagnetronsupplycurrentshavebeenrecordednot to be nominal The supply current on the primary side of the High Voltage transformer is nominally between 7 Amps and 9 Amps In case of a damaged high voltage component this current usually drops t...

Страница 31: ...rily i e as long as a button is depressed or a one minute prolonged test This can be used to ensure the control and magnetrons are working accordingly During the test amperage to each Magnetron circuit can be safely measured on the output of the Solid State Relay which completes this circuit By pressing the SELECT button the soft keys at the bottom of the screen change to TEST MAG and 1MIN START T...

Страница 32: ...Microwave Survey Meter for proper operation Make sure that the survey meter you are using has been calibrated and is suitable for measuring frequencies of 2 45GHz Do not exceed meter full scale deflection Leakage meter should initially be set to the highest scale Adjust to lower scales to ensure that low readings are measured on the most sensitive range Set probe sensitivity to slow setting ON A U...

Страница 33: ...D THIS CAPACITOR MUST BE DISCHARGED BEFORE WORKING ON ANY COMPONENTS IN THE HIGH VOLTAGE AREA REFER TO THE DISCHARGING THE HIGH VOLTAGE SYSTEM SECTION OF THE MANUAL FOR PROPER INSTRUCTIONS FOR THIS PROCEDURE READ THE INSTRUCTIONS ON THIS PAGE CAREFULLY BEFORE YOU PROCEED DUE TO THE HIGH VOLTAGE IT IS POSSIBLE TO RECEIVE AN ELECTRIC SHOCK WHEN TOUCHING A NONMETAL PART SUCH AS AN INSULATED CONNECTOR...

Страница 34: ...sing a digital multimeter check the resistance of the windings Results should be as follows a Primary Winding 208V tap to common and 230V tap to common 208V Tap 0 89 5 Ω and 230V Tap 1 01 5 Ω b High Voltage Secondary Winding Anode tap to ground 65 00 5 Ω c Filament Winding Anode tap to Filament Anode tap less than 1Ω 5 Using an insulation resistance tester or Megohmmeter verify the insulation resi...

Страница 35: ...en or ajar Tools Required Digital Multimeter Test Procedure 1 Remove the oven from its power source 2 Removethetoppaneltogainaccesstothemonitor relay 3 Disconnect RED 101 from the relay input contact 4 Disconnect the wires connected to the relay output contacts WHT 97 on the COM and YEL 1S on the NO 5 Measure resistance across the relay NO and COM output contacts should be open Verifies relay cont...

Страница 36: ...ingfansshouldbeoperating NOTE This next step should cause the Test Fuse to trip and verifies proper monitor circuit function 10 Open the door Verify that the Test Fuse trips and remove the oven from its power source 11 Rewire to the original configuration a Remove the jumper wire between wire WHT 99 and the Mains Terminal Block L1 Reconnect wire WHT 99 to COM 1 and BLU 85 to COM 2 on the Voltage R...

Страница 37: ...ire to the original configuration a Disconnect the meter test leads b Reconnect WHT 97 to Terminal Block L2 c Reconnect WHT 98 to the Mag SSR T1 and verify BLK M1 connection d Reconnect WHT 99 COM 1 and BLU 85 COM 2 to the Voltage Relay contacts ...

Страница 38: ...oven door is closed 3 Remove oven top left and right side panels to gain access to the interlock assembly Switches are located at the top corners at the point where oven door latches engage OVEN FRONT Monitor Switch Primary Interlock Switch Monitor top Primary bottom Interlock Switches Right Side of Oven OVEN FRONT Secondary Interlock Switch Secondary Interlock Switch Left Side of Oven 4 Loosen bo...

Страница 39: ...ming process 4 Turn on the power to the drive 5 Press the red STOP button on the inverter control panel CAUTION The inverter and the majority of con trol components are at a 208VAC or 240VAC potential at this point 6 Press the Up key until the Setup Mode STUP screen is displayed 7 Press the Enter key to view the parameter setting display 8 Scroll through parameters by pressing the up key until the...

Страница 40: ...LOCAL REMOTE Run Selection Determines the operation when the Run command source is switched from LOCAL to REMOTE or between Run source 1 and 2 while an external Run command is active at the new source 0 0 0 External Run command has to be cycled at the new source to be activated 1 External Run command at new source is accepted immediately b1 08 Run Command Selection while in Programming Mode 0 0 0 ...

Страница 41: ...ing ramp 0 20 0 20 0 0 to 10 00 s C2 02 S curve Characteristic at Accel End 0 20 0 20 0 0 to 10 00 s C2 03 S curve Characteristic at Decel Start 0 20 0 20 0 0 to 10 00 s C2 04 S curve Characteristic at Decel End 0 20 0 00 0 0 to 10 00 s C3 01 Slip Compensation Gain Sets the slip compensation gain Decides for what amount the output frequency is boosted in order to compensate the slip Note Adjustmen...

Страница 42: ...XX 3 and 5 are on 0 00 0 00 d1 07 Frequency Reference 7 Frequency reference when digital inputs Multi Step Speed Reference 2 3 H1 XX 4 and 5 are on 0 00 0 00 d1 08 Frequency Reference 8 Frequency reference when multi function input Multi Step Speed Reference 1 2 3 H1 XX 3 4 5 are on 0 00 0 00 d1 17 Jog Frequency Reference Frequency reference when digital inputs Jog Frequency Reference Forward Jog ...

Страница 43: ... to 255 0 V E2 01 Motor Rated Current 2 40 1 90 10 to 200 of drive rated current A E2 02 Motor Rated Slip 2 50 2 90 0 00 to 20 00 Hz E2 03 Motor No Load Current 1 49 1 20 0 to less than E2 01 A E2 05 Motor Line to Line Resistance 9 842 9 842 0 000 to 65 000 Ω Multi Function Terminals H1 01 Multi Function Digital Input Terminal S1 Function Selection Assigns a function to the multi function digital ...

Страница 44: ...MEMOBUS Modbus terminals R R S S Cycle power for the setting to take effect 0001F 001F 0 to 32 H5 02 Comm Speed Selection Selects the baud rate for MEMOBUS Modbus terminals R R S and S Cycle power for the setting to take effect 3 3 0 1200 bps 1 2400 bps 2 4800 bps 3 9600 bps 4 19200 bps 5 38400 bps H5 03 Comm Parity Selection Selects the communications parity for MEMOBUS Modbus terminals R R S and...

Страница 45: ...s long as the CPU is working L3 01 Stall Prevention Selection during Acceleration Selects the Stall Prevention method used to prevent excessive current during acceleration 1 1 0 Disabled Motor accelerates at active acceleration rate The motor may stall if load is too heavy or accel time is too short 1 General Purpose When output current exceeds L3 02 level acceleration stops Acceleration will cont...

Страница 46: ...2 Parameter L4 01 sets the level while parameter L4 02 sets the hysteresis for the Speed Detection Output Function 0 0 0 0 0 00 to 400 0 Hz L4 07 Frequency Detection Conditions 0 0 0 No detection during baseblock 1 Detection always enabled L5 01 Number of Auto Restart Attempts Sets the counter for the number of times the drive attempts to restart when one of the following faults occurs oC ov PF rH...

Страница 47: ...low 6 Hz 2 Enabled for the whole speed range Advanced Program Set Up n1 02 Hunting Prevention Gain Setting Sets the gain for the Hunting Prevention Function If the motor vibrates while lightly loaded and n1 01 1 increase the gain by 0 1 until vibration ceases If the motor stalls while n1 01 1 decrease the gain by 0 1 until the stalling ceases 1 00 1 00 0 00 to 2 50 n3 13 Overexcitation Deceleratio...

Страница 48: ... operator copy functions are allowed 1 Enabled Copying allowed o4 01 Accumulated Operation Time Setting Sets the value for the cumulative operation time of the drive 0 0 to 9999 10 hour units o4 02 Accumulated Operation Time Selection Determines how the cumulative operation time U4 01 is counted 0 0 Logs power on time 1 Logs operation time when the drive output is active output operation time o4 0...

Страница 49: ... clean rinse and dry the surface Then on a daily basis apply a high quality stainless steel polish according to manufacturer s instructions Heat Tint Darkened areas called heat tint may appear on stainlesssteelexposedtoexcessiveheat whichcauses the protective film to thicken It is unsightly but is not a sign of permanent damage To remove heat tint follow the routine cleaning procedure Stubborn hea...

Страница 50: ...a water pressure type cleaning system DO NOT use Duke Oven Cleaner or Shield on the exterior of the oven Prevent any water leakage to the oven interior component compartment 1 Clean all exterior surfaces with a mild detergent and warm water solution using a clean cloth or sponge 2 Wipe out rear duct cavity exhaust as necessary Check for a build up of cooking vapors along the discharge louvers in t...

Страница 51: ...cause for activation see SSR Heating SSR not triggered Verify trigger signal from control board Verify supply voltage across SSR If SSR is not switching despite signal and supply are present replace SSR Otherwise determine root cause for absence of either trigger signal control or supply Failed or open fuse Remove fuse and verify conductivity WARNING DISCONNECT UNIT BEFORE TOUCHING LINE VOLTAGE CO...

Страница 52: ... necessary Magnetron SSR not triggered Verify magnetron operation in service screen Both magnetrons have to be inactive Verify trigger signal from control board Verify supply voltage across SSR If SSR is not switching despite signal and supply are present replace SSR Otherwise determine root cause for absence of either trigger signal control or supply Interlock switches damaged Verify operation of...

Страница 53: ...y that convection blowers properly supplied If motor overheats thermal breaker will interrupt motor supply lines from inverter Determine root cause for overheating if applicable Replace if necessary Inverter malfunction Verify connections and programming parameters of inverter Replace reprogram inverter if necessary Control board malfunction Verify function through service screen Verify signal out...

Страница 54: ...U 85 ORN 87 YEL 86 BLU 89 BLU 73 BRN 82 BLK 84 ORN 94 WHT WHT BLK BLK THERMOSTAT 300C THERMOSTAT 275C ORN 95 ORN 87 BRN 82 WHT 99 WHT 81 BLK 84 BLU 19 ORN 21 WHT 17 BLU 19 BLU 18 Bottom Left NC NO NC NO NC 240 NO 208 NO NC NO NC 2 1 230V COIL NO OPTIONAL Snubber NC NO NC COM Low Voltage XFMR Voltage Relay 208 240 Hi Limit Right HEAT ELEMENT 2 HEAT ELEMENT 1 Terminal Block Line Supply 208V 240 1 ø ...

Страница 55: ...___ NORTH AMERICA LATIN AMERICA Duke Manufacturing Company 2305 N Broadway St Louis MO 63102 Phone 314 231 1130 Toll Free 1 800 735 3853 Fax 314 231 5074 UK IRELAND Duke Mfg UK Duke House Unit 10 Greendale Business Park Woodbury Salterton Exeter Devon UK EX5 1EW Tel 01395 234140 FAX 01395 234154 CONTINENTAL EUROPE Duke Manufacturing C R s r o Prologis Park D1 West Building 4 Zdebradska 92 Ricany J...

Страница 56: ...s Park D1 West Building 4 Zdebradska 92 Ricany Jazlovice 251 01 Czech Republic Phone 42 0 257 741 033 Fax 42 0 257 741 039 Duke Mfg UK Duke House Unit 10 Greendale Business Park Woodbury Salterton Exeter Devon UK EX5 1EW Tel 44 0 1395 234140 FAX 44 0 1395 234154 Asia Office Duke Food Service Equipment shanghai Company Limited 1F Building 17 2 658 Nong Jin Zhong Road Shanghai China 200335 Tel 86 21...

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