VERDER CARBOLITE GERO HTF 18/8 Manual

Installation, Operation and Maintenance Instructions
1800°C Chamber Furnace - HTF Model: 8 Litres
3508 Controller
HTF 18/8 + 3508 Controller
MEN-HTF1808-001_3508 (02-08-2019)

Contents
This manual is for guidance on the use of the Carbolite Gero product specified on the
front cover. This manual should be read thoroughly before unpacking and using the
furnace or oven. The model details and serial number are shown on the back of this
manual. Use the product for the purpose for which it is intended.
1.0 Symbols and Warnings 6
1.1 Switches and Lights 6
1.2 Warning Symbols 6
2.0 Installation 8
2.1 Unpacking and Handling 8
2.2 Siting and Setting Up 8
2.3 Fitting the Heating Elements 9
2.4 Electrical Connections 10
2.5 Power Supply Notes 11
3.0 3508 Controller 12
3.1 PID control 12
3.2 3508P1 12
3.3 3508P10 12
3.4 3508P25 12
3.5 Basic Operation 13
3.5.1 Controller Layout 14
3.5.2 Keys 14
3.6 Quick Start Guide 14
3.6.1 Operation as a simple controller 14
3.6.2 Changing the Setpoint 14
3.6.3 Resetting the programmer 15
3.6.4 Understanding User Levels 15
3.7 Setting Up Controller 16
3.7.1 Maximum output power setting 16
3.7.2 Customer ID. 16
3.7.3 Units 17
3.7.4 Language 17
3.8 Programming 17
3.8.1 Programming Notes 17
3.8.2 Holdback 18
3.8.3 Wait Segments 18
3.8.4 Program Cycling 19
3.8.5 Creating a Program 19
3.8.6 Running a Program 20
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3.8.7 To pause (hold) a program 21
3.8.8 To stop and reset a program 21
3.8.9 To run a different program (P10 and P25) 21
3.8.10 Program Status 21
3.8.11 Program Hold with Holdback 22
3.8.12 Power Failure Recovery 22
3.8.13 Alarms 23
3.8.14 Program Example 1 23
3.8.15 Program Example 2 25
3.9 Controller Options 27
3.9.1 Digital Communications - RS232 28
3.9.2 Digital Communications - RS485 28
3.9.3 Comms Address 28
3.9.4 Alarm Option 28
3.9.5 Remote Input and Output (Analogue Communications) 29
3.9.6 Program segment output 29
3.10 Temperature Controller Replacement 30
3.11 Controller Navigation Diagrams 30
3.11.1 Operator Level 1 - No Program Running 31
3.11.2 Operator Level 1 - Program Running 32
3.11.3 Supervisor Level 2 33
4.0 3508 Dual Loop Cascade Control (if fitted) 34
4.1 Principle of Cascade Control 34
4.2 Operation of Cascade Control 34
4.3 Bypassing Cascade Control 38
4.4 3508P1 Element Loop (Loop 2) 38
4.5 Caution 38
4.6 Over-Temperature Control 38
5.0 2132 Over-Temperature Controller Description (if fitted) 39
5.1 Description 39
5.2 Operation 39
5.2.1 Controls 39
5.2.2 Operation 40
5.2.3 Over-Temperature Operation 40
5.2.4 Over-Temperature Alarm 40
5.2.5 Resetting the Over-Temperature Alarm 40
5.2.6 Sensor Break 40
5.3 Audible Alarm 41
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5.4 Navigation Diagram 41
6.0 Operation 42
6.1 Operating Cycle 42
6.2 Operator Safety 42
6.3 Loading The Furnace 43
6.4 Opening the Door 43
6.5 Insulation Cracking 43
6.6 Atmospheres & Corrosive Materials 43
6.7 Pesting 44
6.8 Explosive Materials 44
6.9 Notes on Temperature Control 44
6.10 Thermocouple Warnings 45
6.11 Thermal Cutouts 45
6.12 General Operating Advice 46
7.0 Maintenance 47
7.1 General Maintenance 47
7.2 Maintenance Schedule 47
7.2.1 Cleaning 49
7.2.2 Safety Switch 49
7.2.3 Other Electrical Components 49
7.2.4 Element Glaze 50
7.3 Calibration 50
7.4 After-Sales Service 50
7.5 Recommended Spare Parts and Spare Parts Kit 50
7.6 Power Adjustment (Controller) 50
7.7 Power Adjustment (Thyristor) 51
7.8 Low Voltage Compensation 51
8.0 Repairs and Replacements 52
8.1 Safety Warning - Disconnection from Power Supply 52
8.2 Safety Warning - Refractory Fibre Insulation 52
8.3 Side Panel Removal 52
8.4 Thyristor Replacement and Adjustment 53
8.5 Temperature Controller Replacement 53
8.6 Fuse Replacement 54
8.7 Thermocouple Replacement 54
8.8 Element Installation and Replacement 54
8.9 Insulation Replacement 57
8.10 Transformer Tappings 57
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8.11 Fuse Replacement 58
9.0 Fault Analysis 60
A. Furnace Does Not Heat Up 60
B. Product Overheats 61
10.0 Wiring Diagrams 62
10.1 Single Phase 208 V, 220-240 V 62
10.2 Two phase 380/ 220 V - 415/ 240 V 63
11.0 Fuses and Power Settings 65
11.1 Fuses 65
11.2 Power Settings 65
12.0 Specifications 67
12.1 Environment 67
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1.0 Symbols and Warnings
1.0 Symbols and Warnings
1.1 Switches and Lights
Instrument switch: when the instrument switch is operated the
temperature control circuit is energised.
Heat light: the adjacent light glows or flashes to indicate that power
is being supplied to the elements.
1.2 Warning Symbols
DANGER – Electric shock. Read any warning printed next to this
symbol.
WARNING: Risk of fatal injury.
DANGER – Hot surface. Read any warning printed next to this
symbol.
WARNING: All surfaces of a product may be hot.
DANGER – Read any warning printed next to this symbol.
FAULT - read any information printed by this symbol.
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Caution – Double Pole/Neutral Fusing
7
1.0 Symbols and Warnings

2.0 Installation
2.0 Installation
2.1 Unpacking and Handling
When unpacking or moving the product always lift it by its base. Do not use the door or
any other protruding parts. The product contains a transformer and is heavy: use two or
more people to carry the product.
Remove any packing material from the door great and from inside the product
chamber. Close the door with care to prevent any damage to insulation surfaces.
NOTE: This product contains Refractory Ceramic Fibre (also known as
Alumino Silicate Wool - ASW). For precautions and advice on handling
this material see section 8.2.
2.2 Siting and Setting Up
Place the product on a level surface in a well ventilated area.
Site away from other sources of heat and on a non-flammable surface that is resistant
to accidental spillage or hot materials.
The surface on which the equipment is mounted should be stable and not subject to
movement or vibrations.
The height of the mounting surface is important to avoid operator strain when loading
and unloading samples.
Unless otherwise stated elsewhere in this manual, ensure that there is at least 150
mm of free space around the back and sides of the product. Clear space is required
above the product to dissipate heat.
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If the product is to be used in a process which could liberate hazardous gases, then it
should be installed together with a suitable fume extraction system.
Ensure that the product is placed in such a way that it can be quickly switched off or
disconnected from the electrical supply.
Under no circumstances should any objects be placed on top of the product.
Always ensure that any vents on the top of the product are clear of any
obstruction. Always ensure all cooling vents and cooling fans (if fitted) are
clear of any obstruction.
2.3 Fitting the Heating Elements
Please refer to the Element Installation and Replacement in section 8.0.
Wear eye protection when handling the heating elements.
The molybdenum disilicide elements are EXCEPTIONALLY FRAGILE and
are packed separately, together with other items shown in the list.
Separately Packed Items 1800 °C Models
Elements 5
Element Clamps 10
Element Clips 10
Braids 1 set of 6
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2.0 Installation

2.0 Installation
Separators/ Block 5
Chimney Unit 1
The installation of these elements is described in section 0.1.
2.4 Electrical Connections
Connection by a qualified electrician is recommended.
These models are designed only for single phase electrical supplies, or for two live
phases and neutral of a 3-phase supply. The product must be connected only to the type
and voltage of supply for which it was ordered.
Check that the supply voltage is compatible with the voltage on the label, and that the
current capacity is sufficient for the current on the label, before connection to the
electrical supply. A table of the most common ratings is given in section 11.0 towards
the back of this manual.
Normally a supply cable is not fitted, and connection is to be made to terminal blocks
accessed by removal of the left-hand end side cover (see section 8.3). The electrical
supply cable must be properly connected and fitted with an appropriate strain relief at
the entry to the case.
The electrical supply cable should be wired to an isolator or fitted with a line plug. The
isolator must be within easy reach of the operator, or the line plug must be easily
removable and on a lead not exceeding 3 m length. The line plug must allow the
protective earth (ground) to be connected before the supply conductors and to be
disconnected after them. The supply point must be marked as the disconnecting device
for the furnace.
The electrical supply MUST incorporate an earth (ground).
Supply Terminal Label Cable Colour
Supply Types
Live - Neutral Reversible or Live-
Live
1-phase L Brown to live
to either power
conductor
(For USA 200-240V,
connect L1)
N Blue to neutral
to the other power
conductor
(For USA 200-240V,
connect L2)
PE Green/ Yellow to earth
(ground) to earth (ground)
Electrical Connection Details:
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2-phase L1 Black to phase 1
L2 Black to phase 2
N Light Blue to neutral
PE Green/ Yellow to earth (ground)
2.5 Power Supply Notes
Each model is manufactured for one of the following voltage ranges:
l208 V
l220 to 240 V
l380 to 415 V (not HTF 17/5 or HTF 18/4)
It is not possible to modify and use a furnace manufactured for the 380-415 range on
either of the other two voltage ranges listed above: there are too many component
differences.
It is possible to modify a furnace manufactured for either 208 and 220-240, provided
the thyristor unit is replaced. A transformer tapping must also be altered. See sections
8.4 and 8.10.
It is possible to alter the voltage within any of the ranges above, by reconnecting the
incoming cable to the transformer to the appropriate primary tapping. The tappings are
208 - 220 - 230 - 240 V, or 380 - 400 - 415 V, and are labelled on the primary side of
the transformer - see section 8.10. It is also necessary to adjust the setting of the
thyristor stack: see section 8.4.
Examples:
lto alter a furnace made for a 240 V supply to 208 V: replace thyristor stack,
move a cable to the 208 V transformer tapping, and adjust the thyristor stack.
lto change from a supply of 220 V to 230 V: move a cable to the 230 V, and
adjust the thyristor stack.
Please contract Carbolite Gero Service for guidance and assistance if the power supply
shown on the rating label does not match the power supply available.
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2.0 Installation

3.0 3508 Controller
3.0 3508 Controller
3.1 PID control
This controller uses PID (Proportional Integral Derivative) temperature control. This
type of control uses a complex mathematical control system to adjust the heating power
and achieve the desired temperature.
3.2 3508P1
The 3508P1 is a digital temperature controller which uses PID algorithm to give
excellent temperature control when properly set. This controller can store and operate a
single program of up to 20 segments. The 3508P1 can also be used as a simple
temperature controller.
3.3 3508P10
The 3508P10 is a digital controller which uses PID algorithms to give excellent
temperature control when properly set. This controller can store 10 programs of up to
50 segments each. Programs can be operated individually or linked by a Call parameter
as sub-programs or to form single long programs. The 3508P10 can also be used as a
simple temperature controller.
3.4 3508P25
The 3508P25 is a digital temperature controller which uses PID algorithms to give
excellent temperature control when properly set. This controller has a maximum of 500
segments or 25 programs; each program has a maximum of 50 segments. For example
3508P25 could store 10 programs with 50 segments or 25 programs with 20 segments.
Programs can be operated individually or linked by a Call parameter as sub-programs or
to form single long programs. The 3508P25 can also be used as a simple temperature
controller.
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3.5 Basic Operation
Key
A Alarm Indicator
B Power Output Indicator
C Not Used
D Runs, Holds, Resets the current program
E Page
F Scroll
G Down
H Up
I Power Output Percentage
JProgram Setpoint Temperature (PSP) when a program is
running
K Setpoint Temperature (SP) when basic controlling
L Measurement Temperature
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3.0 3508 Controller
M Measurement Units
3.5.1 Controller Layout
3.5.2 Keys
A/ Man - Disabled
RUN/ HOLD - Runs, Holds or Resets the current program. Hold down for 3
seconds to Reset.
Page Key Scrolls through the page headings. Hold down for 3 seconds to
access further levels, pass codes are required.
Scroll Key Scrolls through parameters listed on pages.
Arrow Keys +Adjust parameter values.
Page and
Scroll
together +Press together to return to the home display or to
acknowledge an alarm.
Page and Up
together +Press together quickly to scroll back up the page headings.
Scroll and Up
together +Press together quickly to scroll back up a parameter list.
Pressing any other combination of keys together has no effect.
Note: If no keys are pressed for 1 minute, the display returns to Home.
3.6 Quick Start Guide
3.6.1 Operation as a simple controller
When switched on the controller goes through a short test routine and then shows the
measured temperature. Below it, the setpoint temperature (SP) and percentage of
power output.
The controller will immediately attempt to reach the set temperature and maintain it.
This will cause the product to heat as quickly as possible which may not be appropriate
where the product contains sensitive ceramic components. For products with ceramic
components, e.g. a tube furnaces fitted with a long ceramic work tube, use the ramp
rate feature set with a low heating rate such as 5°C per minute (300°C per hour), to
prevent damage.
3.6.2 Changing the Setpoint
Press up or down to select the required SP. If the SP is higher than the measured
temperature, the OP1 indicator will illuminate at the top of the display, indicating that
the product is heating.
The controller will immediately attempt to reach the set temperature and maintain it.
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This will cause the product to heat as quickly as possible which may not be appropriate
where the product contains sensitive ceramic components. For products with ceramic
components, e.g. a tube furnaces fitted with a long ceramic work tube, use the ramp
rate feature set with a low heating rate such as 5°C per minute (300°C per hour), to
prevent damage.
3.6.3 Resetting the programmer
To reset the programmer to simple controller mode, press RUN/HOLD for 2 seconds.
Operating the current program
• To avoid unwanted heating at the end of a program, set the SP temperature to zero
before operating a program.
• Ensure the programmer is reset to simple controller mode before starting a program
by pressing RUN/HOLD for 2 seconds.
• To start the program, press RUN/HOLD twice, RUN will light up on the display.
The displayed Program Setpoint (PSP) follows ramps, dwells and steps as the program
runs. The SP temperature of the controller does not apply when a program is
operating.
• To pause the program, press RUN/HOLD.
• To stop the program and return to simple controlling (reset), press RUN/HOLD for 2
seconds.
When the program ends, the programmer will either:
• Automatically reset to operation as a simple controller.
• Dwell at the last temperature of the program (with the RUN indicator flashing), until
the operator presses RUN/HOLD for 2 seconds to manually reset, or presses RUN/HOLD
once to restart the program.
• Turn power to the elements down to zero.
3.6.4 Understanding User Levels
There are two levels in the controller; Level 1(Operator) and Level 2 (Supervisor).
Level 1 (Operator) is for the day-to-day operation of the controller is not protected by a
security code. There are 3 pages at this level. Page 1, Customer Identity, can only be
altered in level 2. Page 2 shows the current program status. Page 3 is for writing and
viewing programs.
Level 2 (Supervisor) requires a security code to enter, but once enable, provides access
to additional parameters. A further 4 pages are accessible in this level as follows; Home
, Customer identity, Control Output Hi percentage, Units.
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3.0 3508 Controller

3.0 3508 Controller
To Enter Level 2:
1. Press and hold page for 3 seconds. The display will show “Access Goto Level 1”
2. Press up to select level 2. After a short pause the display will show “Access
Pass code”.
3. Press up or down to enter the pass code. Pass is momentarily displayed.
After a short pause the display will return to home, the controller is now in level 2.
When Level 2 operations have been completed the supervisor must return to Level
1 manually. It is not necessary to enter a code when going from a higher level to a
lower level.
To Return to Level 1:
1. Press and hold page for 3 seconds. The display will show “Access Goto Level 2.
2. Press down to go to level 1. After a short pause the display will revert to
home, the controller is now in level 1.
3.7 Setting Up Controller
Before using the controller (or during its lifetime) certain parameters may have to be
set, depending on specific requirements. To do this the controller must be set to
Supervisor Level 2, see "Controller Navigation Diagrams".
3.7.1 Maximum output power setting
Press page until "Control Output Hi" is displayed. Press up or down to adjust
the value.
Depending on the product model, the maximum power output setting may be accessible
or locked.
For silicon carbide heated products the parameter is accessible to allow compensation
for element ageing.
In many models the maximum power output setting depends on the electrical supply
voltage, refer to section 11.0.
3.7.2 Customer ID.
A product identity number can be entered if required. This may be used to identify one
of many units, for production or quality control systems.
Press page until "Customer Identity" is displayed. Press up or down to select a
number.
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3.7.3 Units
Press page until "Units" is displayed. Press up or down to select:
C Celsius
F Fahrenheit
K Kelvin
3.7.4 Language
The text on the 3508 Controller can be shown in different languages, this can only be
set at the factory and therefore must be specified at the time of placing an order.
3.8 Programming
3.8.1 Programming Notes
Programs can be created in Level 1 or Level 2 of the 3508 Controller.
For the P10 and P25, new programs can be created while the current program is
operating.
To avoid unwanted heating at the end of a program, set the controller setpoint
temperature to zero before operating a program.
All new unused programs show only 1 segment of type 'End'.
The minimum number of segments for a program is 2. The second being an 'End' type.
Ramp-to-setpoint control. To achieve this, create a two segment program. Set the first
segment type as 'Rate' or 'Time'. Set the second segment type 'End' type' Dwell'.
For the P10 and P25, programs can be linked together using a 'Call' segment. However,
a lower number program can not be called and a program can not be ended with a call
segment.
A program can be ended in four ways:
1. With 'End' segment set to S.OP the power to the elements is turned down to 0%,
no matter what the 'Setpoint' temperature is.
2. With 'End' segment set to 'Reset' and the 'Setpoint' temperature turned down to
zero, power to the elements will be 0%. To do this set the 'Setpoint' temperature
to the minimum possible. For type B thermocouples this will be below zero.
3. With the 'End' segment set to 'Reset'. The controller will try to reach and maintain
the 'Setpoint' temperature in place before the program started.
4. With the 'End' segment set to 'Dwell'. The controller will dwell at the 'PSP' of the
last segment ("RUN" indicator flashes), until it is reset.
To reduce the number of segments in a program, change the last required segment to
an 'End' type.
You will be asked to press to cancel or for OK.
To cancel all segments in a program, change the first segment to an 'End' type.
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3.0 3508 Controller

3.0 3508 Controller
To alter parameters or segments of an operating program, this program must be held
or reset. Press RUN/ HOLD to pause the program, or press RUN/ HOLD for 2 seconds to
reset.
3.8.2 Holdback
Holdback can be used to prevent the program from operating ahead of the actual
heating or cooling.
The holdback value is the amount, in degrees, by which the program setpoint can run
ahead of the measured temperature before holdback operates. The value applies to a
whole program.
To set the value press page twice, press scroll until 'Holdback Value' appears and
press up or down to set.
Holdback can be used in 'Rate', 'Time' and 'Step' segments.
• For 'Rate' and 'Time' segments holdback will operate during the segment.
• For a 'Step' segment holdback delays continuation to the next segment until the step
target is reached.
The 'Holdback Type' can be set as follows:
• Low Applies to heating only
• High Applies to cooling only
• Band Applies to both heating and cooling
• Off Holdback is switched off
To set the holdback type, press page twice, then press scroll until the display
shows 'Holdback Type' for each segment and press up or down to set.
The default setting for holdback is 'OFF'.
3.8.3 Wait Segments
Wait prevents the program proceeding to the next segment, in a similar way to
holdback, until the selected ‘Wait-For’ parameter has been met. There are 5 ‘Wait For’
parameters. The first 4 only work if there are configured inputs to the controller.
1. PrgIn1 Wait until Input 1 is true
2. PrgIn2 Wait until Input 2 is true
3. PrgIn 1&2 Wait until Inputs 1 AND 2 are true
4. PrgIn 1or2 Wait until Inputs 1 OR 2 is true
5. PVWaitIP Wait until the measured temperature reaches a threshold value before
continuing. It can operate in one of 4 ways:
1. 'Abs Hi' Wait until the measured temperature is greater than or equal to a
value 'WaitVal' set for that segment.
2. 'Abs Lo' Wait until the measured temperature is less than or equal to a value
'WaitVal' set for that segment.
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3. 'Dev Hi’ Wait until the measured temperature exceeds a fixed* threshold by
an amount ‘WaitVal’ set for that segment.
4. ‘Dev Lo’ Wait until the measured temperature drops below a fixed* threshold
by an amount ‘WaitVal’ set for that segment.
* The fixed threshold used by deviation parameters is set in the configuration level of
the programmer and if required should be requested when purchasing a product from
Carbolite Gero.
3.8.4 Program Cycling
The 'Cycles' parameter sets the number of times the program will operate.
The default setting is 1 cycle.
To change the number of cycles, press page twice, then press scroll until the
display shows 'Prog Cycles', then press up to set a finite number of cycles up to 999.
Or press down to set cycling to continuous.
3.8.5 Creating a Program
From the home display, press page three times to get to the programming page,
the display will show “ProgEdit 1”.
Program number
On P10 or P25 models press up or down to select a new program number. The
display will show that new programs have only one segment.
Holdback Value
Press scroll until the display shows 'Holdback Value". If required: Press up or
down to set a value. This value will be used in any segment where a 'Holdback Type'
is set.
Ramp Units
These apply to Rate segments only. Press scroll until the display shows 'Ramp Units'.
Press up or down to select the ramp units of degrees per Hour, Min or Sec.
Number of program cycles
Press scroll until the display shows 'Cycles'. Press up or down to select more
than one cycle.
Now create all the segments for your program, finishing with an 'End' segment. When
parameters for each segment have been entered the display goes to the next segment
number.
Segment Type
Press scroll until the display shows 'Segment Type'. Press up or down to select
'Rate', 'Time', 'Dwell', 'Step', 'Wait', 'GoBack', 'Call' or 'End'.
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3.0 3508 Controller

3.0 3508 Controller
Holdback Type
Press scroll until the display shows 'Holdback Type'. If required, press up or down
to select 'Off', 'Low', 'High' or 'Band'.
Target Setpoint (Visible only for Rate, Time and Step segments)
Press scroll until the display shows 'Target SP'. Press up or down to set a value.
Ramp Rate (Visible only for Rate segments)
Press scroll until the display shows 'Ramp Rate'. Press up or down to set the
number of degrees per 'Ramp Unit' as set above.
Duration (Visible only for Time and Dwell segments)
Press scroll until the display shows 'Duration". Press up or down to set a value.
Wait For (Visible only for Wait segments)
Press scroll until the display shows 'Wait For'. Press up or down to select:
PrgIn1, PrgIn2, PrgIn1In2, PrgIn1orIn2, PVWaitIP.
GoBack to segment number (visible only for GoBack segments)
Press scroll until the display shows 'GoBack Seg'. Press down to select a segment
number to go back to.
GoBack Cycles (visible only for GoBack segments)
Press scroll until the display shows 'GoBack Cycles'. Press up or down to set a
value.
Call Cycles (Visible only for call segments)
Press scroll until the display shows 'Call Cycles'. Press up or down to set a
value.
End Type (Visible only for End segments)
Press scroll until the display shows 'End Type'. Press up or down to select:
'Reset', 'Dwell' or 'SafeOp'.
3.8.6 Running a Program
The current program can be started from the home display by pressing RUN/HOLD or by
pressing page once, then scroll once (twice for P10 and P25), then press up or
down to change the status to 'Run'.
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