Despatch LBB2-xxA-B-2 User Manual
LBB Series Oven Owner’s Manual PREFACE
LBB SERIES OVEN
LBB SERIES OVENLBB SERIES OVEN
LBB SERIES OVEN
C-188
Version 18 1
OWNER’S
OWNER’S MANUAL
OWNER’S OWNER’S
MANUAL
MANUALMANUAL
PN 336979
VERSION 18
6/2014
PREFACE LBB Series Oven Owner’s Manual
2 Version 18
Revision History
Revision Date Author Description
C Updated electrical drawings in DRAWINGS AND
SPARE PARTS LISTS section.
D Corrections.
E Correction, page 19, set-up parameter table
F Parts lists corrections in DRAWINGS AND SPARE
PARTS LISTS section
G Corrections to SPECIFICATIONS section, addition of
options and features in APPENDIX
H Change Product Warranty page
I Update drawings and High Limit information
J Parts lists corrections in DRAWING AND SPARE
PARTS LISTS section. Corrected Despatch address.
K Parts lists corrections in DRAWING AND SPARE
PARTS LISTS section
L Updated warranty
12 3/2011 Livingston Revise format
13 9/2011 Livingston Additional parts tables
14 6/2012 Livingston Update for Protocol 3
15 8/2012 Livingston Corrections—Power Section.
15 7/2013 Livingston Corrections—Minor correction to header.
16 8/2013 Meyer Correction to LBB2-12 spare parts list
17 2/2014 Livingston Minor copy changes. Remove LBB1-43 references.
17.1 4/2014 Livingston Revised schematics added plus various small changes.
18 5/2014 E. Anderson R3 REV -2 modifications
LBB Series Oven Owner’s Manual PREFACE
Version 18 3
PREFACE LBB Series Oven Owner’s Manual
4 Version 18
LBB Series Oven Owner’s Manual PREFACE
Version 18 5
Table of Contents
1. About This Manual ............................................................................................................. 8
1.1. Important User Information ..................................................................................... 8
1.2. Manufacturer & Service .......................................................................................... 9
1.3. Organization of this Manual .................................................................................... 9
1.4. Conventions ........................................................................................................... 10
1.5. Specifications ........................................................................................................ 11
1.5.1. Dimensions ........................................................................................................ 11
1.5.2. Capacities .......................................................................................................... 12
1.5.3. Power ................................................................................................................. 13
1.5.4. Temperature ....................................................................................................... 14
1.5.5. LBB Series Oven Operating Conditions ........................................................... 14
2. Safety ................................................................................................................................ 15
2.1. Safety Information ................................................................................................. 15
2.1.1. Lockout .............................................................................................................. 15
2.1.1.1. Lockout Requirements ................................................................................... 15
2.1.1.2. Lockout Procedure ......................................................................................... 15
2.2. Provisions for Lifting and Carrying....................................................................... 16
2.3. Maintenance .......................................................................................................... 16
2.4. Electrical Power ..................................................................................................... 16
2.5. Fire ......................................................................................................................... 17
2.6. Equipment Lockout Requirements ........................................................................ 17
2.6.1. Emergency Stop ................................................................................................. 18
2.7. Disconnecting Devices .......................................................................................... 18
2.7.1. Power Requirements .......................................................................................... 18
2.7.2. Disconnecting Hard-Wired Units ...................................................................... 18
2.7.3. Disconnecting Corded Units .............................................................................. 19
2.7.4. Disconnecting Units with (Optional) Disconnect Switch .................................. 19
3. Theory of Operation ......................................................................................................... 20
3.1. The LBB Series Oven ............................................................................................ 20
3.1.1. Oven Theory ...................................................................................................... 21
3.2. Control Systems..................................................................................................... 21
3.2.1. Primary Control Instrument ............................................................................... 21
3.2.2. High Limit Instrument ....................................................................................... 22
3.2.2.1. Product High Limit Instrument ...................................................................... 23
3.2.2.2. Oven High Limit Instrument ......................................................................... 23
3.3. The Protocol 3 Controller (Optional) .................................................................... 23
4. Assembly & Setup ............................................................................................................ 24
4.1. Unpack & Inspect the LBB Series Oven ............................................................... 24
4.1.1. If Damaged During Shipping ............................................................................ 24
4.2. Set-up the LBB Series Oven .................................................................................. 24
4.2.1. Select Oven Location/Operating Environment .................................................. 24
4.2.2. Set-up Procedure ............................................................................................... 25
4.2.3. Wiring & Power Connections ........................................................................... 25
5. Operation .......................................................................................................................... 28
5.1. Load Oven ............................................................................................................. 28
5.2. Pre-Startup Checklist ............................................................................................. 29
5.3. Operating Procedure—Standard Control Instrument ............................................ 30
5.3.1. Start Oven .......................................................................................................... 30
5.4. Working with the Control Instrument ................................................................... 32
PREFACE LBB Series Oven Owner’s Manual
6 Version 18
5.4.1. Change Setpoint................................................................................................. 32
5.4.2. Control Instrument Parameter Programming Mode .......................................... 33
5.4.2.1. Entering Control Instrument Set-up and Configuration Mode ...................... 33
5.4.2.2. Control Instrument Operating Mode Notes ................................................... 34
5.4.3. Change Control Instrument Display from Centigrade to Fahrenheit ................. 35
5.4.4. Oven Zone Calibration ...................................................................................... 36
5.4.5. Set the High Limit ............................................................................................. 37
5.4.5.1. Change the High Limit Instrument Setpoint .................................................. 37
5.4.6. High Limit Instrument Parameter Setup Mode ................................................. 37
5.4.7. High Limit Instrument Setup Parameters .......................................................... 38
5.4.8. Change High Limit instrument Display from Centigrade to Fahrenheit .......... 39
5.5. Working with Optional Protocol 3 Controller Operating Modes .......................... 39
6. Maintenance ..................................................................................................................... 40
6.1. Checklist ................................................................................................................ 40
6.2. Lubrication ............................................................................................................ 41
6.3. Cleaning and Decontamination ............................................................................. 41
6.3.1. Cleaning the LBB Series Oven .......................................................................... 41
6.3.2. Decontaminating the LBB Series Oven ............................................................. 42
6.4. Routine Tests ......................................................................................................... 42
6.4.1. Test Control Instrument ..................................................................................... 43
6.4.2. Test High Limit Instrument ............................................................................... 43
6.5. Replacement Parts ................................................................................................. 43
6.5.1. Replace the Control Instrument ......................................................................... 44
6.5.2. Replace High Limit Instrument ......................................................................... 47
6.5.3. Replace (Optional) Protocol 3 Controller .......................................................... 49
6.5.4. Replace Heater Unit .......................................................................................... 49
6.5.5. Replace Fan Motor ............................................................................................ 51
7. Troubleshooting................................................................................................................ 54
Table 7. Common Technical Issues and Remedies. ...................................................................... 54
7.1. DES2000 Control Parameters Check .................................................................... 55
7.2. Hi Limit L91 Hi-Limit Reset ................................................................................. 57
8. Appendices ....................................................................................................................... 58
8.1. Standard Products Warranty .................................................................................. 58
8.2. Optional Equipment ............................................................................................... 59
8.2.1. Assemble Oven Stand ........................................................................................ 59
8.2.2. End of Cycle (EOC) Timer Option.................................................................... 60
8.2.3. Operating the Timer .......................................................................................... 61
8.2.4. Parameter Default Settings ................................................................................ 63
8.2.5. Timer Option with Audible and Visual Alarm .................................................. 63
8.2.6. High Alarm Limit Option .................................................................................. 63
8.3. Part Lists ................................................................................................................ 64
8.4. Mechanical Drawing ............................................................................................. 64
8.5. Electrical Schematics ............................................................................................. 64
LBB Series Oven Owner’s Manual PREFACE
Version 18 7
Figures
Figure 1. Disconnect Switch.......................................................................................................... 19
Figure 2. LBB Forced Convection Benchtop Oven. ..................................................................... 20
Figure 3. Uniflow Airflow through the LBB Oven. ...................................................................... 20
Figure 4. LBB Series Oven Primary Control Instrument .............................................................. 21
Figure 5. High Limit Instrument. .................................................................................................. 22
Figure 6. Protocol 3 Operator Interface. ........................................................................................ 23
Figure 7. LBB Series Oven Name Plate Example. ........................................................................ 26
Figure 8. LBB Series Oven with Top Removed. ........................................................................... 26
Figure 9. Wiring Access through Rear of Oven. ........................................................................... 27
Figure 10. Close-up of Connector Block. ...................................................................................... 27
Figure 11. LBB Series Oven Control Panel. ................................................................................. 31
Figure 12. Adjust Damper to Set Exhaust Vent by rotating the outer component. ....................... 31
Figure 13. Remove Control Panel to Access Control Instrument (using T20 Torx bit driver). .... 44
Figure 14. Providing easy access to the Control instrument. ........................................................ 45
Figure 15. Remove old Control and High Limit Instruments and Wiring (Rear View). ............... 45
Figure 16. Prepare to remove control instrument by removing the mounting bracket. ................. 46
Figure 17. Connections to Control Instrument. ............................................................................. 46
Figure 18. High Limit Connector Block on Control Board. .......................................................... 47
Figure 19. Press and Hold Tabs to Remove High Limit Instrument. ............................................ 48
Figure 20. Connections to High Limit Instrument. ....................................................................... 48
Figure 21. Remove Screws to Remove Each Duct (using T15 Torx bit driver. ............................ 49
Figure 22. Heater element connections. ........................................................................................ 50
Figure 23. Typical Heating Element (Inset connections see Figure 22) . ...................................... 51
Figure 24. Fan Motor Location. .................................................................................................... 52
Figure 25. Separate fan wheel from fan motor shaft. .................................................................... 53
Figure 26. Optional LBB Oven Stand. .......................................................................................... 59
Figure 27. Timer Option Displays and Switches. .......................................................................... 60
Figure 28. LBB1-23 Mechanical Drawing .................................................................................... 65
Figure 29. LBB1-69 Mechanical Drawing .................................................................................... 66
Figure 30. LBB2-12 Mechanical Drawing .................................................................................... 67
Figure 31. LBB2-18 Mechanical Drawing .................................................................................... 68
Figure 32. LBB2-27 Mechanical Drawing .................................................................................... 69
Figure 33. LBB Standard (120 V) Schematic................................................................................ 70
Figure 34. LBB Standard (240 V) Schematic................................................................................ 71
Figure 35. LBB Opt P-3 (120 V) Schematic. ................................................................................ 72
Figure 36. LBB Opt P-3 (240 V) Schematic. ................................................................................ 73
Tables
Table 1. Operating/Environmental Conditions (For indoor use). .................................................. 14
Table 2. Control Instrument Explanations. .................................................................................... 22
Table 3. High Limit Instrument Explanations. .............................................................................. 22
Table 4. Control Instrument Set-up Parameters. ........................................................................... 33
Table 5. Control Instrument Configuration Parameters. ............................................................... 34
Table 6. High Limit instrument Setup Parameters. ....................................................................... 38
Table 7. Common Technical Issues and Remedies. ...................................................................... 54
ABOUT THIS MANUAL LBB Series Oven Owner’s Manual
8 Version 18
1. About This Manual
1.1. Important User Information
Copyright © 2014 by Despatch Industries.
All rights reserved. No part of the contents of this manual may be reproduced, copied, or
transmitted in any form or by any means including graphic, electronic, or mechanical methods or
photocopying, recording, or information storage and retrieval systems without the written
permission of the publisher, unless it is for the purchaser's personal use.
Produced in the United States of America.
The information in this manual is subject to change without notice and does not represent a
commitment on the part of Despatch Industries. Despatch Industries does not assume any
responsibility for any errors that may appear in this manual.
In no event will Despatch Industries be liable for technical or editorial omissions made herein,
nor for direct, indirect, special, incidental, or consequential damages resulting from the use or
defect of this manual.
Values displayed on screens are examples only. Though
those values may be typical, contact Despatch Industries for
the final value.
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 5 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.
LBB Series Oven Owner’s Manual ABOUT THIS MANUAL
Global Headquarters
Contact
Service & Technical
Despatch Industries
Version 18 9
Danger!
Only fully-trained and qualified personnel should setup and
maintain this equipment. Improper setup and operation of this
equipment could cause an explosion that may result in
equipment damage, personal injury or possible death.
The information in this document is not intended to cover all possible conditions and situations
that might occur. The end user must exercise caution and common sense when installing or
maintaining Despatch Industries products. If any questions or problems arise, call Despatch
Industries at 1-800-762-0110 or 1-952-469-5424.
1.2. Manufacturer & Service
The LBB Series oven is manufactured by Despatch Industries.
Despatch has specialized in thermal processing for over 100 years. Technical expertise gained
over those years helps provide innovative solutions to critical applications in vertical markets and
cutting edge technology worldwide. Despatch products are backed by a drive for long-term
customer satisfaction and a strong sense of responsibility. The worldwide network of factorytrained Service Professionals is available to support your Despatch equipment. From full service
preventive maintenance to routine repair and certified calibration and uniformity, the Despatch
service network is positioned to respond to your business needs. Our service programs are
customized to meet your specific needs using our Advantage Service Assurance Program
(ASAP). For more information on ASAP, visit www.despatch.com.
International/Main: 1-952-469-5424
8860 207th Street
Lakeville, MN 55044
USA
US toll free: 1-800-726-0110
Fax: 1-952-469-4513
info@despatch.com
www.despatch.com
1.3. Organization of this Manual
This owner’s manual contains the most comprehensive set of information for the Despatch LBB
Series ovens, including installation instructions, theory of operation, and operating instructions,
among other things.
Support
Service: 1-952-469-8230
US toll free: 1-800-473-7373
Service @despatch.com
ABOUT THIS MANUAL LBB Series Oven Owner’s Manual
10 Version 18
Danger!
Failure to heed warnings in this instruction manual and on the
oven could result in personal injury, property damage or death.
1.4. Conventions
This icon signifies information that describes an unsafe
condition that may result in death, serious injury, or damage to
the equipment.
Danger is the signal word used to indicate a hazardous
Danger!
Warning!
Caution!
Notice
situation that, if not avoided, will result in death or severe
injury.
Warning is the signal word used to indicate a hazardous
situation that, if not avoided, could result in death or severe
injury.
Caution is the signal word used to indicate a hazardous
situation that, if not avoided, could result in moderate or minor
injury.
Notice is the signal word used to indicate a hazardous situation
that, if not avoided, could result in property damage.
This icon signifies important supplemental information.
LOG OUT
Bold, 10 point sans-serif typeface indicates a specific key or
button on screen to click.
LBB Series Oven Owner’s Manual ABOUT THIS MANUAL
LBB
Chamber
Size
Capacity
Overall Size
Shelves
Maximum
Chamber
W0 D H W D H
Version 18 11
1.5. Specifications
1.5.1. Dimensions
Model
No.
1-23 18
1-69 30
2-12 30
2-18 37
2-27 37
(46)
(76)
(76)
(94)
(94)
in (cm)
18
(46)
18
(46)
20
(51)
24
(61)
37
(94)
3
feet
(liters)
12
(30)
22
(56)
35
(89)
35
(89)
35
(89)
The LBB oven is not intended to process solvents or other volatile
or flammable materials. Oven exhaust is intended for cooling
purposes only.
2.3
(65)
6.9
(195)
12.1
(343)
18
(510)
27.7
(785)
(102)
(102)
24
(61)
34
(86)
36
(91)
43
43
in (cm)
23
(58)
23
(58)
25
(64)
29
(74)
42
(107)
26
(66)
36
(91)
51
(130)
51
(130)
51
(130)
Provided
on Shelf
Centers
in (cm)
2 on 2”
(5.1)
2 on 2”
(5.1)
2 on 2”
(5.1)
2 on 2”
(5.1)
2 on 2”
(5.1)
Number of
Shelf
Positions
5 1
10 2
16 2
16 2
16 2
Doors
Warning!
Do not place this oven in an environment harmful to electrical
components.
Placing this oven in an environment detrimental to electrical
components (for example, environments where carbon fibers, coal
dust or similar contaminants may be present) may result in
component failure.
Do not use liquids in the oven. Do not set product or liquids on top
of the oven. Liquids that may spill on the oven floor or top of oven
may cause considerable damage to the oven.
Contact Despatch for options available to help prevent such
failures.
ABOUT THIS MANUAL LBB Series Oven Owner’s Manual
LBB Model Number
1-23 1-69 2-12 2-18 2-27
12 Version 18
1.5.2. Capacities
Capacity
Maximum Load
Lbs (Kg)
Maximum Shelf Load
Lbs (Kgs)
Exhaust Capacity
CFM (LPS)
*LBB1-69 and larger models have reinforced shelves.
200
(91)
50
(23)
1
(0.5)
Maximum load capacity not valid on ovens with the
“control panel located on bottom” option.
Warning!
Do not exceed a total of 400 Lbs. (181 Kg) for stacked LBB1-69
ovens.
400
(181)
200*
(91)
3
(1.4)
600
(272)
200*
(91)
12
(5.7)
600
(272)
200*
(91)
14
(6.6)
600
(272)
200*
(91)
14
(6.6)
LBB Series Oven Owner’s Manual ABOUT THIS MANUAL
Heater
Version 18 13
1.5.3. Power
If the line voltage for your LBB Series oven varies more than 10% from the oven voltage rating,
electrical components such as relays and temperature controls may operate erratically.
• If the line voltage is lower than the oven voltage rating, heat-up time may be significantly
longer and motors may overload or run hot.
• If the line voltage is higher than the nameplate rating, motors may run hot and draw excessive
amperage.
Model Volts Amps Hertz Phase
LBB 1-23 120 11.6 50/60 1 1.2 Included, 15 Amp
LBB 1-23 240 5.8 50/60 1 1.2 Included, 15 Amp
LBB 1-69* 120 21.6 50/60 1 2.4 None, Hardwired
LBB 1-69* 240 10.8 50/60 1 2.4 None, Hardwired
LBB 2-12* 240 16.6 50/60 1 3.6 None, Hardwired
LBB 2-18* 240 16.7 50/60 1 3.6 None, Hardwired
LBB2-27* 240 21.7 50/60 1 4.8 None, Hardwired
* Models LBB1-69, LBB2-12, -18 and -27 must be hardwired to the electric supply using 10 AWG or
larger wire suitable for at least 75 °C (167 °F).
KW
Cord and Plug
Ovens designed for 240 volts (check your oven nameplate for power
requirement) will operate satisfactorily on a minimum of 208 volts, but
with a 25% reduction in heater power. If your power characteristics are
lower, contact Despatch industries.
ABOUT THIS MANUAL LBB Series Oven Owner’s Manual
LBB Model
Number
1-23 1-69 2-12 2-18 2-27
Item
Description
14 Version 18
1.5.4. Temperature
Temperature and Parameters
Time to
temperature
(approximate
minutes with no
load)
Recovery time with
door open 1 minute
(approximate
minutes with no
load)
Temperature
uniformity at:
Operating range with 20°C
ambient:
Control stability
40°C-
150°C
40°C-
204°C
150°C 2 3 3 3 4
204°C 4 6 6 7 8
150°C +/- 3°C +/- 3°C +/- 2°C +/- 3°C +/- 3°C
204°C +/- 4°C +/- 4°C +/- 3°C +/- 4°C +/- 4°C
17 15 15 17 17
30 26 30 33 33
35°C- 204°C 40°C-204°C
± 0.5 °C
Dampers must be open to operate at the minimum
temperature.
“Time to Temperature” and “Temperature Uniformity”
values are based on 240V/60 Hz operation, with control
panel located on top. Actual results may vary slightly
depending on unit configuration and operating conditions.
1.5.5. LBB Series Oven Operating Conditions
The LBB Series oven is for indoor use. Table 1 provides the operating conditions.
Table 1. Operating/Environmental Conditions (For indoor use).
Operating Temperature* 18°C to 40°C (64.4°F to 104° F)
Relative Humidity
Maximum Altitude 2,000 meters (6,600 feet)
* Fluctuations in temperature can occur at elevated ambient temperature values.
70% non‐condensing
LBB Series Oven Owner’s Manual SAFETY
Version 18 15
2. Safety
2.1. Safety Information
Do not work on the LBB Series oven without reading and understanding this section, which
contains important information and warnings. Ignoring these warnings can result in death, serious
injury or damage to the machine and product.
2.1.1. Lockout
Carefully follow the established Lock Out Tag Out policies of
Machine lockout places the LBB Series oven into a zero energy state and prevents accidental
machine start up. Always follow the Lockout Procedure described in this section before cleaning,
maintaining or repairing the LBB Series oven. An accidental start-up, while working on the LBB
Series oven, can result in serious injury or death.
your company in all cases.
2.1.1.1. Lockout Requirements
1. Every power source that can energize any element of the LBB Series oven must be shut off at
the closest possible power source. This includes air, water and electricity, including the
Disconnect Switch.
2. After energy sources are locked out, test to ensure circuits are de-energized.
2.1.1.2. Lockout Procedure
Danger!
Electrical panels contain high voltage. Disconnect and lock out
the power supply before working inside any electrical panels.
Failure to lock out the power supply can result in death or injury.
Personnel authorized to lock out equipment must have the necessary locks to perform the lockout.
1. Physically disconnect all electrical power to the machine or lock out the appropriate breaker
or disconnects.
2. Close all valves and bleed off any pressure.
3. Test for power by attempting a start with the machine controls.
4. Identify the Lockout Condition with a tag on the electrical disconnect and pneumatic shut off
valve.
5. When work is complete, remove all tags and restore the machine to its working state.
SAFETY LBB Series Oven Owner’s Manual
16 Version 18
2.2. Provisions for Lifting and Carrying
Caution!
Do not tilt oven while lifting. Do not lift oven using the door
handle to prevent damage to the oven and/or personnel
involved.
Caution!
Do not risk injury when lifting equipment. Take proper
precautions when lifting, carrying or otherwise maintaining
heavy items.
Notice
2.3. Maintenance
Only qualified and trained personnel should perform maintenance or repair.
2.4. Electrical Power
Only qualified and trained personnel should perform electrical maintenance or electrical repair.
How to lift the different sizes of ovens:
• LBB1-23: Four people lift oven’s lower corners and place
on wheeled transport pallet. Push pallet to desired site
and lift oven from pallet, again lift using lower corners.
• LBB1-69, LBB2-12, LBB2-18, LBB2-27: Do not lift by
hand. Lift with fork lifter and transport pallet.
Danger!
Contact with energized electrical sources may result in serious
injury or death.
LBB Series Oven Owner’s Manual SAFETY
Version 18 17
• Before performing maintenance, disconnect all electrical power from the machine. Use a
padlock and lock out all disconnects feeding power to the machine.
• Never clean or repair the oven when in operation.
• Unauthorized alterations or modifications to LBB Series oven are strictly forbidden. Never
modify any electrical circuits. Unauthorized modifications can impair the function and safety
of the LBB Series oven.
Warning!
Do not place this oven in an environment harmful to electrical
components.
Placing this oven in an environment detrimental to electrical
components (for example, environments where carbon fibers,
coal dust or similar contaminants may be present) may result
in component failure.
Do not use corrosive liquids or flammable solvents in the
oven. Do not set product or liquids on top of the oven.
Liquids that may spill on the oven floor or top of oven may
cause considerable damage to the oven.
Contact Despatch for options available to help prevent such
failures.
2.5. Fire
Keep the LBB Series oven clean and free of scrap materials, oil or solvents to prevent the
possibility of fire. In the event of fire:
1. Leave door (s) as they are.
2. De-energize the machine immediately by turning OFF the
all power.
3. Turn off the remote main disconnect (customer supplied disconnect).
4. Shut off fuel
5. Call the fire department or use a fire extinguisher to extinguish the fire.
Danger!
Always disconnect all power before extinguishing a fire.
Attempting to extinguish a fire in a machine connected to
electrical power can result in serious injury or death!
2.6. Equipment Lockout Requirements
To prevent injury or equipment damage during inspection or repair, the LBB Series oven must be
locked out.
DISCONNECT SWITCH or removing
SAFETY LBB Series Oven Owner’s Manual
18 Version 18
2.6.1. Emergency Stop
When a risk of personal injury or damage to the LBB Series oven exists, turn OFF the oven by
either the disconnect switch or removing/unplugging the cord. This shuts off all electrical power
to the oven.
2.7. Disconnecting Devices
2.7.1. Power Requirements
Despatch recommends the LBB Series Ovens have unobstructed access to a dedicated power
source.
Use a power stabilizer if voltage fluctuation is greater than ±10%
nominal voltage fluctuation.
2.7.2. Disconnecting Hard-Wired Units
LBB permanently-connected (hard-wired) ovens include models LBB1-69, LBB2-12, LBB2-18
and LBB2-27. Permanently-connected and multi-phased equipment must employ a switch or
circuit-breaker as means for disconnection.
For permanently-connected equipment, installation instructions
Notice
The disconnecting device must be installed in close proximity to the equipment and within easy
reach of the operator. The disconnecting device must be marked as the disconnecting device for
the equipment. If the unit is equipped with an ON/OFF switch, mark the ON/OFF position
clearly.
must specify a switch or circuit-breaker be included during the
facility oven installation for complete isolation.
Follow local codes and requirements for installing and using
disconnect switches.
LBB Series Oven Owner’s Manual SAFETY
Version 18 19
Danger!
Keep switch or circuit-breaker in building installation close to
the equipment, within easy reach of the operator and clearly
marked.
2.7.3. Disconnecting Corded Units
LBB cord-connected ovens includes model LBB1-23. To disconnect a corded unit, unplug the
cord from the power source.
2.7.4. Disconnecting Units with (Optional) Disconnect Switch
The LBB Series oven has an optional Disconnect Switch (Figure 1).
This Disconnect Switch is located on the front of the oven and is
connected to the load break switch behind the panel that disconnects or
connects power from the main line. When a risk of personal injury or
damage to the LBB Series oven exists, turn off the Disconnect Switch.
This shuts off all electrical power to the oven.
Figure 1. Disconnect
Switch.
THEORY OF OPERATION LBB Series Oven Owner’s Manual
20 Version 18
3. Theory of Operation
3.1. The LBB Series Oven
The Despatch LBB Series ovens (Figure 2) effectively distribute heat with a processing time
among the fastest of any lab oven in its class. LBB Series ovens are effectively used in testing,
preheating, sterilizing, drying, aging and curing as well as other production applications. The
LBB Series ovens incorporate forced circulating airflow with precise digital control to deliver fast
processing. The overall result is efficient productivity under strenuous
conditions.
The LBB Series ovens are precise and practical. The unique Despatch
design moves convected heat through stainless steel ducts on each side
of the oven (Figure 3). The air is circulated with a high volume fan.
The LBB Series ovens employ higher volume fans than any
competitive model. The chamber can be densely loaded without
interfering with the process. For your convenience the fresh air intake
is fixed. The exhaust rate is regulated by a damper on the back of the
Figure 2. LBB Forced Convection
Benchtop Oven.
unit.
Heater Recirculation Fan
Exhaust
Figure 3. Uniflow Airflow through the
LBB Oven.
LBB Series Oven Owner’s Manual THEORY OF OPERATION
Version 18 21
Warning!
Do not remove the hat bracket as it distributes exhaust air and
protects the exhaust opening from being completely covered.
3.1.1. Oven Theory
The LBB Series forced circulating oven uses fans to circulate air through the chamber. A
circulating oven is a much more efficient and uniform oven than a gravity-convection oven due to
the constant air movement. Soaking at a desired setpoint still depends on a number of parameters
including chamber area, load mass, the ability to absorb heat and the exhaust rate. But soak times
with a forced circulating oven may be shortened.
The LBB Series oven is capable of heating to 204°C (400°F). The oven uses a
microprocessor-based digital control to display the actual chamber temperature at the sensing
point. The temperature sensor is located to optimize control action for the entire chamber for
various load conditions. The control display may fluctuate a few degrees around the setpoint,
reflecting temperature changes at the sensor location. However, overall chamber temperature
remains stable. The strategic location of the sensor compensates for delays in heat convection and
enhances the performance and temperature control of the oven. The oven has been designed for
an overall result of quality productivity where fast processing and versatility are critical.
3.2. Control Systems
3.2.1. Primary Control Instrument
The LBB Series oven is equipped with a
microprocessor-based digital control instrument
configured as a proportional controller and set to
its optimum operating values (Figure 4). Initially
the control instrument allows the heater to
operate at full power. As the actual oven
temperature reaches the setpoint, the control
instrument cycles the heater on and off,
minimizing process temperature fluctuations.
Table 2 provides explanation for working with
the control instrument.
Figure 4. LBB Series Oven Primary Control Instrument
THEORY OF OPERATION LBB Series Oven Owner’s Manual
Features
Description
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Table 2. Control Instrument Explanations.
Display Description
Main (PV) Display
Key
SP Lit when setpoint value displays
OUT Lit when control calls for heat
AL1 –2 N/A
Typically displays actual oven temperature. Press SET/ENT to display
setpoint. Displays parameter code and value.
Press to switch between PV and SP displays. Enter data using or . Press
repeatedly to switch through parameter displays.
Decrease setpoint or mode parameter
Increase setpoint or mode parameter
3.2.2. High Limit Instrument
The LBB Series oven is equipped with a High
Limit instrument (Figure 5). The High Limit
instrument protects the oven or product by
discontinuing the heating process when the High
Limit is exceeded.
Set the High Limit instrument to a temperature
10°C - 14°C higher than the control instrument
setpoint, or to a temperature that should not be
exceeded in the process. If the setting on the High
Limit instrument is exceeded, the heater shuts
down. See
High Limit instrument.
Table 3 for explanation about the
Figure 5. High Limit Instrument.
Reset the High Limit instrument by pressing RESET on the
instrument.
Table 3. High Limit Instrument Explanations.
OP1 Output 1 status value. (OP2 normally not used for LBB Ovens).
°C/°F
PV Process value
HSP1 High Limit setpoint 1. (LSP1 typically not used for LBB Ovens).
SP2 Setpoint 2 for output 2 (typically not used for LBB Ovens)
LOCK Lock status indicator
Degree indicator.: Celsius or Fahrenheit
Scroll Key, used for advancing available displays
LBB Series Oven Owner’s Manual THEORY OF OPERATION
Features
Description
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Increases a setpoint or mode parameter
Decreases a setpoint or mode parameter
Reset the High Limit, return to normal display
3.2.2.1. Product High Limit Instrument
If the product being processed has a critical high temperature limit, use the High Limit instrument
as a product High Limit instrument. Set the High Limit instrument to a temperature somewhat
below the temperature at which the product could be damaged.
3.2.2.2. Oven High Limit Instrument
If the product being processed does not have a critical high temperature limit, use the High Limit
as an oven High Limit instrument to protect the oven equipment. Set the High Limit to 204°C.
3.3. The Protocol 3 Controller (Optional)
The Protocol 3™ controller is a microprocessor based digital temperature controller designed for
simple and flexible oven operation (Figure 6). The Protocol 3 controller operates as a dualfunctioning controller/High Limit instrument. The control portion utilizes a time proportioning
voltage signal to control heating devices with minimal temperature fluctuations.
The High Limit portion protects the product and/or the oven from overheating. If the product
being processed has a critical high temperature limit, the High Limit setpoint should be set to a
temperature somewhat below the temperature at which the product could be damaged. If the
product does not have a critical high temperature limit, the High Limit setpoint should be set 5 to
15 degrees higher than the maximum programmed setpoint at which the oven will operate.
The Protocol 3 controller provides
three primary operating modes:
• Manual: Oven operates
continuously at a fixed
temperature until turned off.
• Timer: Oven operates at a fixed
temperature for a user-selected
time period, and then
automatically turns off.
• Profile: Temperatures increase
or decrease as defined by 255
segments that can be allocated
to 64 ramp and soak profiles.
The profiles can be linked to provide additional temperature combinations.
Review the Protocol 3 Controller Owner’s Manual for more information.
Figure 6. Protocol 3 Operator Interface.
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