LEB SERIES OVENS INSTRUCTION MANUAL C-189 PN 146231 REVISION I 8/2007
NOTICE Users of this equipment must comply with operating procedures and training of operation personnel as required by the Occupational Safety and Health Act (OSHA) of 1970, Section 6 and relevant safety standards, as well as other safety rules and regulations of state and local governments. Refer to the relevant safety standards in OSHA and National Fire Protection Association (NFPA), section 86 of 1990.
Despatch Industries Advantage Service Assurance Program (ASAP) CONTACT: DESPATCH SERVICE AGREEMENTS SPECIALIST at 800-473-7373 or 952-469-8230 or e-mail: service@despatch.com Despatch continues to deliver exceptional products backed by a strong sense of responsibility and drive for long term customer satisfaction. Your partnership with Despatch can offer even higher value through your subscription to one of Despatch’s Advantage Service Assurance Program(ASAP).
PREFACE This manual is your guide to the Despatch oven. It is organized to give you the information you need quickly and easily. Read the entire INTRODUCTION and THEORY OF OPERATION before installing the oven. An efficient way to learn about the oven would be to read the manual while working with the corresponding oven control system. This will give you practical WARNING: Failure to heed hands-on experience with information in the manual warnings in this instruction and the oven.
Revision B: drawings updated Revision C: drawings updated Revision D: updates to Specifications section; addition of stand assembly and stacking kit assembly instructions Revision E: Corrections, additional drawings added, addition of options and features in APPENDIX Revision F: Update Drawings, Product Warranty, and hi-limit information Revision G: Update Drawing Revision H: Parts lists corrections in DRAWING AND SPARE PARTS LISTS section.
TABLE OF CONTENTS PREFACE ........................................................................................................................ i INTRODUCTION............................................................................................................. 1 Special Features.......................................................................................................... 1 SPECIFICATIONS ...................................................................................................
LEB 1-69-1 (120 VAC) Parts.................................................................................. 40 LEB 1-69-1 (120 VAC) Drawing ............................................................................. 41 LEB 1-69-1 (240 VAC) Parts.................................................................................. 42 LEB 1-69-1 (240 VAC) Drawing ............................................................................. 43 LEB2-18-1 Parts.....................................................
INTRODUCTION The INTRODUCTION section provides an overview of the Despatch LEB Series Ovens. The LEB Series Ovens have the most effective heat distribution and the fastest processing time of any lab ovens their size. Air is discharged from the floor plate of the oven and distributed through the chamber. Special Features • The sturdy construction and high grade insulation of the Despatch LEB Series ovens contribute to excellent high temperature performance.
SPECIFICATIONS Dimensions Model Chamber Size Capacity 3 inches (cm) feet W D H (liters) Overall Size inches (cm) W D H Shelves Provided on Shelf Centers Maximum Number of Shelf Positions Chamber Doors LEB1-23 18 18 12 (46) (46) (30) 2.3 (65) 24 23 26 (61) (58) (66) 2 on 2" 5 1 LEB1-69 30 18 22 (76) (46) (56) 6.
Power Line voltages may vary in some geographical locations. If your line voltage is much lower than the oven voltage rating, warm up time will be longer and motors may overload or run hot. If your line voltage is higher than nameplate rating, the motor may run hot and draw excessive amps. If the line voltage varies more than 10% from the oven voltage rating, some electrical components such as relays, temperature controls, etc. may operate erratically.
Temperature Model 1-23 Time to Temperature 25°C - 100°C (approximate minutes 25°C - 150°C with no load) 25°C - 204°C Recovery Time 100°C Door Open 1 Min. (approximate 150°C minutes with no load) 204°C Operating Range w/20°C Ambient 12 20 35 2 4 6 LEB 1-69 10 18 30 2.4 4 7 30°C - 204°C 2-18 12 20 36 2.2 4 7 Capacities Model Standard Shelf Capacity Reinforced Shelf Capacity Max Load Capacity Stacked Max Load Capacity LEB1-23 LEB1-69* LEB2-18* 50 lbs. (23 kg.) 50 lbs. (23 kg.) 50 lbs. (23 kg.
THEORY OF OPERATION The Despatch LEB Series Ovens have the most economical approach when productivity and ease of operation are the deciding factors. These ovens are especially useful for testing, preheating, sterilizing, drying, aging and curing as well as other production applications. Gravity convected airflow with precision digital control to deliver fast processing. The overall result is efficient productivity under strenuous conditions. The LEB Series Ovens are precise and practical.
CONTROL Instrument The oven is equipped with a microprocessor based digital control instrument. The Despatch CONTROL instrument has been configured as a proportional controller and set to its optimum operating values. Initially, the CONTROL will allow the heater to operate at full power. However; as the actual oven temperature reaches the setpoint, the Proportional Control will cycle the heater on and off, minimizing process temperature fluctuations.
HI-LIMIT Instrument The oven is equipped with a HI-LIMIT instrument. The purpose of the HI-LIMIT instrument is to provide a protective measure for the product and/or the oven itself. If the setting on the HI-LIMIT is exceeded, the heating process will discontinue, thus protecting the product and/or the oven. Set the HI-LIMIT instrument to a temperature 10°C - 14°C higher than the CONTROL instrument setpoint or a temperature that should not be exceeded in the process.
Product HI-LIMIT Instrument If the product being processed has a critical high temperature limit, the HI-LIMIT instrument should be used as a product HI-LIMIT instrument. The HI-LIMIT instrument should be set to a temperature somewhat below the temperature at which the product could be damaged. Oven HI-LIMIT Instrument If the product does not have a critical high temperature limit, the HI-LIMIT can be used as an oven HI-LIMIT instrument. An oven HI-LIMIT instrument protects oven equipment.
Oven Theory The oven has an efficient gravity convected airflow to 204°C (400°F). A gravity convected oven relies on gravity to move air through the chamber. The process of moving air by relying on gravity is a slow responding process. Thus, the overall chamber temperature takes a finite amount of time (roughly a few minutes) to soak in at the desired operating temperature. The time that it takes the unit to soak in at setpoint is related to such parameters as chamber area, load mass, and exhaust rate.
INSTRUCTIONS The INSTRUCTIONS section provides directions on unpacking, installation, operation and maintenance of the Despatch LEB Series Ovens. Unpacking and Inspection Remove all packing materials and thoroughly inspect the oven for damage of any kind that could have occurred during shipment. • See whether the carton and plastic cover sheet inside carton are still in good condition. • Look at all outside surfaces and corners of the oven for scratches and dents.
Setup 1. Place oven on a bench top or an optional stand. The oven must have a minimum of two (2) inches clearance in the rear to provide proper ventilation. The oven may be placed next to another cabinet, or next to another oven, with three (3) inch clearance (the doors will still open). Make sure oven is level and plumb; this will assure proper heat distribution and operation of all mechanical components. 2. Identify correct power source indicated on the specification plate.
Operating Users and operators of this oven must comply with operating procedures and training of operating personnel as required by the Occupational Safety and Health Act (OSHA) of 1970, Section 5 and relevant safety standards, and other safety rules and regulations of state and local governments. Refer to the relevant OSHA and National Fire Protection Association (NFPA) safety standards.
Pre-Startup Checklist Know the system. Read this manual carefully. Make use of its instructions and explanations. The know how of safe, continuous, satisfactory, troublefree operation depends primarily on the degree of your understanding of the system and of your willingness to keep all parts in proper operating condition. Check line voltage. Voltage must correspond to nameplate requirements of motors and controls. Refer to the section on power connections in the INTRODUCTION of this manual.
Startup For fastest oven heat-up time, close the exhaust vent. After the desired temperature is reached, the vent may be adjusted as needed. WARNING: Do not use flammable solvent or flammable material in this oven. Do not process closed containers of any substance or liquid in this oven because they may explode under heat. 1. Start oven. a. Turn POWER switch to on. The circulating fan will start. b. Set exhaust vent to desired opening.
c. Press key to enter setpoint. d. Press key again to display process temperature. 4. Turn HEATER switch to the on position. When process value on the CONTROL reaches setpoint, the OUT LED will cycle on and off to maintain the temperature setpoint. The OUT LED will be lit when the control is calling for heat. 5. Turn the HEATER switch off after heating cycle is complete. Do not turn the fan off until the oven chamber temperature is below 100°C (212°F).
Control Instructions The oven has been tested and preset at the factory for normal operating conditions. In most applications, it will not be necessary to alter the oven's settings, except for the Setpoint. This section contains information and reference material to change Setpoint, display from °C to °F, and access the Operating and Set-up modes. This section also covers oven zone calibration for the CONTROL.
Parameter Programming Mode The control parameters are set through the Operating and Set-up modes. In most applications, it is not necessary to alter the oven settings. The following instructions describe how to access, view and, if desired, change the parameters. WARNING: Make sure you understand what you are changing before doing so. Changing the program parameters will alter the functions of the CONTROL. Once the Operating and Set-up modes are accessed, the SP LED will start blinking on and off.
Operating Parameter Outline Code Control Mode CtL At P I d nr HyS Ct FL bS LoC Name Auto-tuning Proportional Band Integral Time Derivative Time Manual Reset (only when I & d are OFF) Hysteresis (only when CtL is ONF, change CtL to PID) Cycle Time Input Filter PV Bias (Offset) Key Lock Settings PID OFF 4 (8 if °F)* 15 0 N/A N/A 1 0 0 1 *If P is not displayed the Control Mode (CtL) must be first set to PID.
bS PV Bias - Expressed in degrees from –199 to 999. This parameter is used to set the actual oven temperature to the controller display. LoC Key Lock - This provides levels of access to the controller. 0 = No key lock, full access to controller. 1 = Prevents changing of all parameters except setpoint. 2 = Prevents all parameters from being changed including the setpoint. -1 = Set to enter the Setup parameter setting display. The controller is set to LoC=1 at the factory.
Changing Display From °C To °F The control can be configured for either °C or °F. Use the following steps to change control from displaying °C to °F. for three (3) seconds. 1. Press and hold the 2. The display will read CtL. The SP LED will flash indicating that Operating Parameter mode has been entered. 3. Press the until LoC appears on the display. Press the or to enter the parameter. 4. Press the to set the value to –1.
Oven Zone Calibration The CONTROL instrument has been tested and calibrated at the factory. Under normal operating conditions, recalibration should not be necessary. However, if the user would like to recalibrate the CONTROL for a specific operating condition, then recalibration is easily accomplished. Set-Up Parameters (Equipment needed: temperature measuring device with a Compatible Temperature sensor) 1. Verify that the bS (PV Bias) programmed in the CONTROL is 0.
HI-LIMIT INSTRUCTIONS The oven has been tested and the HI-LIMIT preset at the factory for normal operating conditions. In most applications, it will not be necessary to alter the oven's settings, except for the Setpoint. This section contains information and reference material to change Setpoint, access the Set-up mode and change display between °C and °F. WARNING: Failure to heed warnings in this manual and on the oven could result in death, personal injury or property damage.
Parameter Setup Mode The HI-LIMIT parameters are set through the Operating and Set-up modes. In most applications, it is not necessary to alter the oven settings. The following instructions describe how to access, view and, if desired, change the parameters. WARNING: Make sure you understand what you are changing before doing so. Changing the setup parameters will alter the functions of the HI-LIMIT. If the on the HI-LIMIT is lit, press and hold the for four (4) seconds to enable the and keys.
Setup Parameters Note: When changing between °C and °F, the setup parameters Filt, o1.Hy, HSP.L, and HSP.H settings convert automatically. Code Name Settings inPt Input type. J_tC unit Process unit. °C (or °F) rESo SHif Filt out1 o1.Hy Display resolution. PV shift value (offset). PV filter. Output 1 function. Output 1 hysteresis value. No.dP 0 0 Hi. 2.0 HSP.L Lower limit of HSP1. 0 (32 if °F) HSP.H Upper limit of HSP1. out2 Addr bAud PAri diSP Output 2 function.
set. out2 Output 2 function. (N/A) Addr Address assignment for digital communication. (N/A) bAud Baud rate of digital communication. (N/A) PAri Parity bit of digital communication. (N/A) out2 Output 2 function. (N/A) diSP Normal display format – used to select the display in normal condition. PV = Process value. SP1 = HI-LIMIT setpoint. SAFE = the word safe in normal condition.
Changing Display From °C To °F The HI-LIMIT can be configured for either °C or °F. Use the following steps to change HI-LIMIT from displaying °C to °F (and for changing back to °C). 1. If the on the HI-LIMIT is lit, press and hold the for four (4) seconds to enable the and keys. 2. Press and hold the been entered. 3. Press the or or 6. Press the parameter. 7. Press the key for four (4) seconds, the setup mode has now key until the unit is displayed. 4. Press the 5.
Maintenance Do not attempt any service on this oven before opening the main power disconnect switch. Checklist Keep equipment clean. Gradual dirt accumulation retards airflow. A dirty oven can result in unsatisfactory operation such as unbalanced temperature in the work chamber, reduced heating capacity, reduced production, overheated components, etc. Keep the walls, floor and ceiling of the oven work chamber free of dirt and dust.
Tests Tests should be performed carefully and regularly. The safety of personnel as well as the condition of equipment may depend upon the proper operation of any one of the functions of these controls. Test the CONTROL instrument every 40 hours. Check that the CONTROL instrument OUT LED is cycling on and off. Also, verify that the heater is working. WARNINGS: Failure to heed warnings in this manual and on the oven could result in death, personal injury or property damage.
Control Instrument (Tools needed: one-quarter (¼) inch socket set screwdriver with Torx drive) 1. Disconnect power. 2. Remove screws from the face of the control panel and slide it forward. 3. Remove wires from the old control instrument, noting which wires connect to which terminals. Connections to the CONTROL Instrument 4. Disconnect the CONTROL mounting bracket. 5. Remove old CONTROL instrument from control panel. 6. Install new CONTROL instrument into the control panel. 7.
Replacement of Hi-limit Instrument (Tools needed: one quarter (¼) inch socket set; screwdriver) 1. Disconnect power. 2. Remove screws from the face of the control panel and slide it forward. 3. Disconnect HI-LIMIT PLUG from circuit board. 4. Disconnect the thermocouple wires. 5. Press and hold down the tabs holding the HI-LIMIT instrument to the control panel and slide it out. Connections to HI-LIMIT Instrument 6. Install new HI-LIMIT instrument into the control panel. 7. Replace mounting screws. 8.
Heater Unit (Tools needed: 3/8” wrench, screwdriver, one-quarter (¼) inch socket set with Torx drive) 1. Remove shelves. 2. Remove side ducts (right and left) a. Remove screws from each duct. b. Remove duct from oven. 3. Remove heater cover. a. Remove screws from heater cover. b. Remove heater cover from oven. 4. Disconnect heater leads from heater element with wrench. Note which wires go on which terminals. 5. Remove screws holding the heater frame to the oven body. 6. Remove heater and discard. 7.
Troubleshooting Equipment which operates for long periods of time may develop problems. Below are possible problems and suggested solutions. If you have a problem not listed and do not know what to do, contact Despatch industries at our toll-free Help Line 800-473-7373. Difficulty Failure to heat Slow heat up Frequent heater element burnout.
Difficulty Probable Cause Exhaust air vent Heater does not shutdown until temperature reaches the HI-LIMIT setting CONTROL instrument malfunction SSR Relay malfunction Door closes into top or bottom latch only. Uneven latch tension adjustment Door will not stay closed. Inadequate latch tension 33 Suggested Remedy Adjust exhaust air vent. Unit will not control at minimum operating temperature with vent(s) closed. Verify control parameters. Replace relay if no output exists.
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DRAWINGS Drawings and parts lists begin on the next page.
LEB 1-23-1 (120 VAC) Parts Part # 144755 140097 142861 057345 165051 144749 007818 145858 148048 008199 146010 145828 006049 150131 119457 125562 Qty. 1 2 1 1 1 1 1 1 1 2 1 2 1 1 1 1 Description Thermocouple Switch For Power And Heater Cord For Muffin Fan Relay Heater SSR Hi-Limit Despatch L91 Control - Des2000 Heater 1.2kw 120/240v Door Seal Door Pull Latch Ay LBB Exhaust Damper Assembly Standard Shelf Control Compartment Muffin Fan Circuit Board 120v Fuse Atdr-01.25A Control Fuse Atdr-12.
LEB 1-23-1 (120 VAC) Drawing 37
LEB 1-23-1 (240 VAC) Parts Part # 144755 140097 142861 057345 165051 144749 007819 145858 148048 008199 146010 145828 006049 150132 119456 125692 Qty. 1 2 1 1 1 1 1 1 1 2 1 2 1 1 1 1 Description Thermocouple Switch For Power And Heater Cord For Muffin Fan Relay Heater SSR Hi-Limit - Despatch L91 Control - Des2000 Heater 1.2kw 120/240v Door Seal Door Pull Latch Ay LBB Exhaust Damper Assembly Standard Shelf Control Compartment Muffin Fan Circuit Board 240v Fuse Atdr-01.00A Control Fuse Atdr-6.
LEB 1-23-1 (240 VAC) Drawing 39
LEB 1-69-1 (120 VAC) Parts Part # 144755 140097 142861 057345 165051 144749 007819 145725 008057 148048 008199 146010 146024 094717 006049 150131 119457 134923 Qty. 1 2 1 1 1 1 1 1 2 1 2 1 2 2 1 1 1 1 Description Thermocouple Switch For Power And Heater Cord For Muffin Fan Relay Heater SSR Hi-Limit - Despatch L91 Control - Des2000 Heater 2.
LEB 1-69-1 (120 VAC) Drawing 41
LEB 1-69-1 (240 VAC) Parts Part # 144755 140097 142861 057345 165051 144749 007819 145725 008057 148048 008199 146010 146024 094717 015229 150132 119456 125562 Qty. 1 2 1 1 1 1 1 1 2 1 2 1 2 2 1 1 2 2 Description Thermocouple Switch For Power And Heater Cord For Muffin Fan Relay Heater SSR Hi-Limit - Despatch L91 Control - Des2000 Heater 2.
LEB 1-69-1 (240 VAC) Drawing 43
LEB2-18-1 Parts Part # 144755 140097 142861 057345 165051 144749 007818 145814 008057 148048 008199 146010 016471 105498 015229 150132 119456 124475 Qty. 1 2 1 1 1 1 3 1 3 1 2 1 2 2 1 1 2 2 Description Thermocouple Switch For Power And Heater Cord For Muffin Fan Relay Heater SSR Hi-Limit - Despatch L91 Control - Des2000 Heater 1.
LEB 2-18-1 Drawing 45
Despatch Customer Service Procedures and Customer Responsibilities To provide the most effective service to our customers under this warranty, all requests for repairs are to be initiated by the Customer by telephone to the Despatch Service Help Line, 800-473-7373. The Standard Period of Maintenance (SPM) is defined as 8 a.m. to 5 p.m. local time, excluding weekends and Despatch Holidays. Calls placed within the SPM will be handled as follows.
Attachment A - Sustained Service Support At Despatch, long term customer satisfaction means more than responding quickly and effectively to our customers' service requirements. It means offering comprehensive customer support well beyond the scope of our initial contractual commitment. Despatch's Service Products Group offers a Full Service Agreement package or a Preventive Maintenance Plus agreement (PM+).
APPENDIX: OPTIONAL FEATURES Protocol Plus Control Option If the oven is equipped with the Despatch Protocol Plus Controller, consult the Protocol Plus manual (included). Timer Option The timer, which is set-up in hours, is used as a countdown timer. When the timer is on, the delayed contact remains closed allowing power to the heater. During the first 20% of the timing cycle, the first LED blinks. During the next 20% of the timing cycle, the first LED stays on and the second LED blinks.
Timer Operation 1. Turn the dials on the timer to the desired time. 2. Turn the Timer switch to ON. The timer is now counting down to zero. 3. Turn the HEATER switch to ON, if it is not already on. 4. When the timer counts down to zero the heater will shut off. 5. To reset the timer, turn the timer switch OFF then to ON. 6. To manually control the time, leave the timer switch OFF. Timer Configuration The timer is configured for XX.X hours from our facility.
9. Apply power to oven, and follow instructions in the timer operation section. Stand Assembly Instructions 1. Install four rubber grommets into holes in the stand. On LEB1-69 stands, the rear grommets mount into the forward set of rear holes. On LEB2-12 stands the rear grommets mount into the set of holes closest to the rear of the stand. 2. Place the oven on top of the stand. The four embossed areas in the bottom of the oven should center in the grommets. 3.
Stacking Kit Assembly Instructions 1. Locate the four stacking kit brackets found in the kit. 2. Place each of the brackets on top of each of the four corners of one of the lower ovens in the stack being assembled. Slide the angle of each bracket into the slots in the embossed area on top of the oven. See the illustration below for placement. 3. Use the four 10-16 x .50 screws included in the kit to attach the brackets to the oven top. 4. Place the upper oven onto the lower one.
Timer Option with Audible and Visual Alarm This option sounds the alarm and a light comes on when the timer times out. Turning the heater switch off will clear the alarm condition. Do not turn the heater switch on before resetting the timer. Turning the timer switch off will also clear the alarm condition but the heater will remain on. Wiring for this option is shown in the DRAWINGS section of this manual.
