VERDER CARBOLITE GERO SNF Manual

Installation, Operation and Maintenance Instructions
900 °C Swelling Number Furnace: SNF
No Controller
SNF + No Controller
MEN-SNF-005_NOCTRL (18-10-2021)

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 4
1.1 Switches and Lights 4
1.2 General Warnings 4
1.3 Prerequisites to Use 5
2.0 Installation 6
2.1 Unpacking and Handling 6
2.2 Siting and Setting Up 6
2.3 Electrical Connections 7
3.0 Temperature Controller 9
4.0 Operation 10
4.1 Operating Cycle 10
4.2 General Operating Advice 10
4.3 SNF Operation 11
4.3.1 Test Method Principle 11
4.4 Required Apparatus 11
4.4.1 Crucible and Lid 11
4.4.2 Calibration Crucible 12
4.4.3 Test Thermocouple 12
4.4.4 Heat Source 12
4.5 SNFCalibration 13
4.6 Operator Safety 15
5.0 Maintenance 16
5.1 General Maintenance 16
5.2 Maintenance Schedule 16
5.2.1 Cleaning 18
5.3 Calibration 18
5.4 After-Sales Service 18
5.5 Recommended Spare Parts and Spare Parts Kit 18
5.6 Power Adjustment 18
6.0 Repairs and Replacements 20
6.1 Safety Warning - Disconnection from Power Supply 20
6.2 Safety Warning - Refractory Fibre Insulation 20
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6.3 Panel Removal 20
6.4 Temperature Controller Replacement 21
6.5 Heating Element Replacement 21
6.6 Thermocouple Replacement 24
6.7 Fuse Replacement 26
6.8 Solid-State Relay Replacement 26
7.0 Fault Analysis 27
A. Furnace Does Not Heat Up 27
B. Product Overheats 28
8.0 Wiring Diagrams 29
8.1 WA-11-00 29
8.2 WA-11-01 30
9.0 Fuses and Power Settings 31
9.1 Fuses 31
9.2 Power Settings 31
10.0 Specifications 32
10.1 Environment 32
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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 General Warnings
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.
Caution – Double Pole/Neutral Fusing
4

1.3 Prerequisites to Use
Prior to the commissioning and use of this product, all personnel involved in its
installation, operation and maintenance must be deemed competent and have:
lRead and understood the information contained within this manual
lReceived the relevant training with regard to safety and operation of the product
lBeen provided with the appropriate PPE (Personal Protective Equipment) required
for the safe operation of this product
Note: The customer is responsible for ensuring that all of the above conditions are
satisfied before the product is commissioned for use.
Note: Unless otherwise specified, the customer is responsible for the
installation of this product and the safe connection of any additional
equipment and gas or liquid supply lines.
Note: Throughout this manual, written instructions are accompanied by
diagrams. Diagrams may be highlighted in different colours and do not
reflect the actual colouration of the product.
Parts that are to be moved are highlighted in YELLOW and are intended to
be fixed to, or removed from, surfaces highlighted in BLUE. Where
applicable, arrows show the direction of movement.
5

2.0 Installation
2.1 Unpacking and Handling
When unpacking and handling the product, always lift it by its base. Do not use the
door or any other projecting cover or component to support the equipment when
moving it. Use two or more people to carry the product where possible.
Carefully remove any packing material from inside and around the product before use.
Avoid damaging the surrounding insulation when removing packing materials.
NOTE: This product contains Refractory Ceramic Fibre (also known
as Alumino Silicate Wool - ASW). For precautions and advice on
handling this material see section 6.2.
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.
6

Ensure that the product is placed in such a way that it can be quickly switched off or
disconnected from the electrical supply.
This product is supplied with a crucible holder (a small component made of wire).
Ensure that this is present.
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 Electrical Connections
Connection by a qualified electrician is recommended.
This product requires a single-phase A.C. supply with earth (ground), which may be
Live to Neutral non-reversible (polarised), Live to Neutral reversible (non-polarised), or
Live to Live.
Check the product rating label before connection. The supply voltage should agree with
the voltage on the label and the supply capacity should be sufficient for the current on
the label.
The supply should be fused at the next size equal to, or higher than the current on the
label. This manual contains a table of the most common fuse ratings.
7

When the mains cable is factory fitted, internal fuses are also fitted. It is essential that
the operator ensures that the product is correctly fused.
Products with a factory fitted supply cable are designed to be wired directly to an
isolator or fitted with a line plug.
Products without a factory fitted supply cable require a permanent connection to a
fused and isolated supply. The product's electrical access panel should be temporarily
removed, and connections made to the internal terminals.
When connecting the product to the power supply, the plug or isolating switch should
be accessible, easy to remove, and within reach of the operator.
The supply MUST incorporate an earth (ground).
Supply Terminal Label Cable Colour
Supply Types
Live - Neutral Reversible or Live-
Live
1-phase L1 Brown to live
to either power
conductor
(For USA 200-240V,
connect L1)
N / L2 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:
8

3.0 Temperature Controller
If this product is fitted with a temperature controller, instructions are provided
separately.
9

4.0 Operation
4.1 Operating Cycle
This product is fitted with an instrument switch which cuts off power to the control
circuit.
Connect the product to the electrical supply.
Turn on the instrument switch to activate the temperature controllers. The controllers
illuminate and go through a short test cycle.
Over-Temperature option only. If the digital over-temperature option has not yet
been set as required, set and activate it according to the over-temperature controller
instructions.
The product will heat up according to the controller setpoint or program, unless a time
switch is fitted and switched off.
As the product heats up, the heat light glows steadily at first and then flashes as the
product approaches the desired temperature. For more information on temperature
control see the controller instructions.
Over-Temperature option only. If the over-temperature circuit has tripped, an
indicator on the over-temperature controller flashes and the heating elements are
isolated. Find and correct the cause before resetting the over-temperature controller
according to the instructions supplied.
To turn the product off, set the instrument switch to its off position. The controller
display will go blank. If the product is to be left unattended, isolate it from the electrical
supply.
4.2 General Operating Advice
Heating element life is shortened by overheating. Do not leave the
product at high temperature when it is not required. The maximum
temperature is shown on the product rating label and in section 10.0
towards the back of this manual.
Lightweight ceramic fibre insulation can easily be marked by
accidental contact. Some fine cracks may develop in the surface of
the insulation due to the progressive shrinkage of the insulation
materials. Cracks are not usually detrimental to the functioning or the
safety of the product.
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4.3 SNF Operation
The SNF furnace is designed to meet the requirement of following test standards:
lASTM D720/D720M-15
lBS ISO 501:2012
These international standards specify a method for determining the swelling properties
of hard coal when heated in a covered crucible.
Note: The "crucible swelling number" (CSN) is also known as the "free swelling
index" (FSI).
4.3.1 Test Method Principle
A sample of coal is heated in a covered crucible under the standard conditions
regarding time and temperature. The shape of the resulting coke sample is classified
by comparison with the outlines of a set of standard profiles.
4.4 Required Apparatus
4.4.1 Crucible and Lid
1 Flat surface required
2 Lid
3 Crucible
(Dimensions in mm)
Figure 1: Squat form silica crucible and silica lid with ring handle
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The crucible should conform to the following specifications:
lExternal height: 26 ± 1.0 mm
lExternal diameter at top: 41 ± 1.0 mm
lInternal diameter at base: 14 ± 3.0 mm
lMass: 12 ± 1.0 g
lCapacity: 16 ml - 17.5 ml
4.4.2 Calibration Crucible
The calibration crucible should have a pierced silica lid, similar to the standard crucible
lid, but with a 6 mm hole through which a thermocouple can pass.
(Dimensions in mm)
Figure 2: CalibrationCrucible Lid
4.4.3 Test Thermocouple
The test thermocouple should be a sheathed fine wire with a diameter no greater than
0.5 mm if made from noble metals, or 0.8 mm if made from base metals.
4.4.4 Heat Source
The heat source can be a gas burner capable of meeting the required standard heating
conditions. Alternatively, an electrical heating system (furnace) may be used, provided
that it is shown to produce results within 0.5 units of those obtained using a gas
heating method, across the whole range of swelling numbers.
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4.5 SNFCalibration
Wear appropriate PPE e.g. heat-resistant gloves, goggles
Danger: Hot surfaces!
Ensure that you have a suitable heat resistant surface on which to place
hot items e.g. crucibles
The SNF is supplied with the following calibration test equipment:
lTest thermocouple support bracket
lTest thermocouple (Type K, 1.5 mm diameter)
lCrucible
lCrucible carrier
To calibrate the furnace:
lAttach the test thermocouple support
bracket to the top of the furnace with the
four screws provided.
lClose the furnace lid.
lPreheat furnace to the required tem-
perature and allow the temperature to
stabilise for at least 2 hours.
lPlace an empty calibration crucible with
pierced lid into the crucible carrier.
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lOpen the furnace lid and insert the cru-
cible carrier into the furnace.
lStart timing the test as soon as the cru-
cible is inserted into the furnace cham-
ber.
lInsert the test thermocouple through the
hole in the test thermocouple support
bracket and down into the crucible via
the hole in the crucible lid. The
thermocouple must be positioned so that
the tip of the thermocouple is in contact
with the base of the crucible.
lMonitor the test thermocouple. The inner
surface of the crucible should reach:
l800°C ±10°C within 1.5 minutes of
insertion into the furnace
l820°C ±5°C within 2.5 minutes of
insertion into the furnace
Note: If the results are outside the required time or temperature parameters, the
two variables that can be adjusted are the furnace temperature setpoint and the time
between opening the SNF lid and inserting the crucible. Make minor adjustments to
meet the conditions of the test standard.
Example:
lIn the example below, the SNF setpoint was 879°C, and the furnace was allowed
to stabilise at temperature for 2 hours.
lThe time between opening the SNFlid and inserting the crucible was 30 seconds.
lThe graph below shows the calibration results where the test thermocouple
temperature passes through the two required time/temperature points.
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4.6 Operator Safety
Ceramic materials used in the furnace insulation can become
conducting at high temperatures; therefore there is a potential
danger to the operator, as this furnace is designed to be used with
the chamber lid open.
To guard against this danger, the furnace is fitted with a 30mA earth leakage (residual
current) circuit breaker mounted in the back of the case. This trips out in the event of
accidental contact with the heating element or current leakage through the insulation.
The device may be reset after tripping out. From time to time, test it using the integral
test button.
15

5.0 Maintenance
5.1 General Maintenance
Preventive rather than reactive maintenance is recommended. The type and frequency
depends on the product use; the following are recommended.
5.2 Maintenance Schedule
CUSTOMER
QUALIFIED PERSONNEL
DANGER! ELECTRIC SHOCK. Risk of fatal injury. Only electrically
qualified personnel should attempt these maintenance procedures.
Maintenance
Procedure Method
Frequency
Daily Weekly Monthly Bi-
Annually Annually
Safety
Over-Temperature Safety
Circuit
(if fitted)
Set an over-temperature setpoint lower than
the displayed temperature and check for an
over-temperature alarm as detailed in this
manual
Over-Temperature Safety
Circuit
(if fitted) Electrical measurement
Lid Insulation Visual inspection, checking the seal and
whether it is free of damage
Lid Insulation Replacement where necessary
Electrical Safety
(external)
Test the 30mA RCD trip with the test button
daily before use.
Electrical Safety
(external) Visual check of external cables and plugs
Electrical Safety (internal) Physically check all connections and cleaning
of the power plate area
Function
Temperature Calibration Tested using certified equipment, frequency
dependent on the standard required
Operational Check Check that all functions are working nor-
mally
Operational Check Thorough inspection and report incor-
porating a test of all functions
16

Performance
Element Circuit Electrical measurement
Power Consumption Measure the current drawn on each phase /
circuit
17

5.2.1 Cleaning
Soot deposits may form inside the furnace, depending on the process. At appropriate
intervals remove these by heating as indicated in the General Operation Notes.
The product's outer surface may be cleaned with a damp cloth. Do
not allow water to enter the interior of the case or chamber. Do not
clean with organic solvents.
5.3 Calibration
After prolonged use, the controller and/or thermocouple may require recalibration. This
is important for processes that require accurate temperature readings or for those that
use the product close to its maximum temperature. A quick check using an independent
thermocouple and temperature indicator should be made from time to time to
determine whether full calibration is required. Carbolite Gero can supply these items.
Depending on the controller fitted, the controller instructions may contain calibration
instructions.
5.4 After-Sales Service
Carbolite Gero Service has a team of Service Engineers who can offer repair, calibration
and preventive maintenance of furnace and oven products both at the Carbolite Gero
factory and at customers’ premises throughout the world. A telephone call or email
often enables a fault to be diagnosed and the necessary parts to be despatched.
In all correspondence please quote the serial number and model type given on the
rating label of the product. The serial number and model type are also given on the
back of this manual when supplied with the product.
Carbolite Gero Service and Carbolite Gero contact information can be found on the
back page of this manual.
5.5 Recommended Spare Parts and Spare Parts Kit
Carbolite Gero can supply individual spare parts or a kit of the items most likely to be
required. Ordering a kit in advance can save time in the event of a breakdown.
Each kit consists of one thermocouple, one solid state relay, one element and one lid
insulation piece.
When ordering spare kits please quote the model details as requested above.
Crucibles with lids and spare crucible holders, can also be supplied.
5.6 Power Adjustment
The control system incorporates electronic power limiting, but for the model listed in
this manual the power limit is set to 100%. The power limit parameter OP.Hi may be
accessible to the operator, but should not generally be altered.
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In some cases the supply voltage may be outside the range 220-240 V or the 3-phase
equivalent, the power limit parameter may be set to a value other than 100%. Do not
increase the value to 100%, see section 9.0 for details of power limit settings.
19

6.0 Repairs and Replacements
6.1 Safety Warning - Disconnection from Power Supply
Immediately switch the product off in the event of unforeseen
circumstances (e.g. large amount of smoke). Allow the product to
return to room temperature before inspection.
Always ensure that the product is disconnected from the electrical
supply before repair work is carried out.
Caution: Double pole/neutral fusing may be used in this product.
6.2 Safety Warning - Refractory Fibre Insulation
Insulation made from High Temperature Insulation Wool
Refractory Ceramic Fibre, better known as (Alumina silicate
wool - ASW).
This product contains alumino silicate wool products in its thermal insulation. These
materials may be in the form of blanket or felt, formed board or shapes, slab or loose
fill wool.
Typical use does not result in any significant level of airborne dust from these
materials, but much higher levels may be encountered during maintenance or repair.
Whilst there is no evidence of any long term health hazards, it is strongly
recommended that safety precautions are taken whenever the materials are handled.
Exposure to fibre dust may cause respiratory disease.
When handling the material, always use approved respiratory protection
equipment (RPE-eg. FFP3), eye protection, gloves and long sleeved clothing.
Avoid breaking up waste material. Dispose of waste in sealed containers.
After handling, rinse exposed skin with water before washing gently with
soap (not detergent). Wash work clothing separately.
Before commencing any major repairs it is recommended to make reference to the
European Association representing the High Temperature Insulation Wool industry
(www.ecfia.eu).
Further information can be provided on request. Alternatively, Carbolite Gero Service
can quote for any repairs to be carried out either on site or at the Carbolite Gero
factory.
6.3 Panel Removal
Except for temperature controller replacement, access to components is by removal of
the top panel. Remove 10 self-tapping screws. Carefully save the 10 spacers (between
20