VERDER Carbolite Gero AX 120 Manual

Installation, Operation and Maintenance Instructions
250°C Laboratory Fan Ovens - Apex Range: 120 Litres
R38 Controller
AX 120 + R38 Controller
MEN-AX120-001_R38 (01-09-2022)

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
2.0 Installation 5
2.1 Unpacking and Handling 5
2.2 Siting and Setting Up 5
2.2.1 Shelf Fitting 7
2.3 Flat Pack Stand (optional) 9
2.3.1 Parts Supplied 9
2.3.2 Flat Pack Stand Assembly 10
2.4 Electrical Connections 11
3.0 R38 Controller 13
3.1 PID control 13
3.2 Controller Operation 13
3.3 R38 Over-Temperature Controller 13
3.4 Process Timer (if fitted) 14
3.5 Calibration 14
3.6 Over-Temperature Control (if fitted) 15
3.7 Controller Replacement 15
3.8 Temperature Controller Replacement 15
4.0 Operation 16
4.1 Operating Cycle 16
4.2 The Oven Door and Chamber 16
4.3 Loading and Unloading the Chamber 16
4.4 Vents 17
4.5 Temperature Control 17
4.6 Explosive Vapours 17
5.0 Maintenance 18
5.1 General Maintenance 18
5.2 Maintenance Schedule 18
5.2.1 Cleaning 20
5.3 After-Sales Service 20
2

5.4 Recommended Spare Parts and Spare Parts Kit 20
5.5 Retrofit Kits 20
6.0 Repairs and Replacements 21
6.1 Safety Warning - Disconnection from Power Supply 21
6.2 Safety Warning - Refractory Fibre Insulation 21
6.3 Panel Removal 21
6.4 Temperature Controller Replacement 22
6.5 Control Sensor Replacement 22
6.6 Solid-state Relay Replacement 23
6.7 Fuse Replacement 23
6.8 Element Replacement 23
7.0 Fault Analysis 24
A. Oven Does Not Heat Up 24
B. Oven Overheats 24
C. Process Timer 25
8.0 Wiring Diagrams 26
8.1 WV-11-00 26
8.2 WV-11-01 27
9.0 Fuses and Power Settings 28
9.1 Fuses 28
9.2 Power Settings 28
10.0 Specifications 29
10.1 Environment 29
3

1.0 Symbols and Warnings
1.1 Switches and Lights
Instrument switch: when the instrument switch is operated the
temperature control circuit is energised.
Door lock indicator: When this lamp is illuminated, the door is locked
and cannot be opened.
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

2.0 Installation
2.1 Unpacking and Handling
Remove the shelves and runners from the packaging before attempting to move the
equipment.
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.
Locate the shelves and runners as required.
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.
5

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.
If the over-temperature option is not fitted, ensure that the unit can be directly
observed.
6

2.2.1 Shelf Fitting
Runner Shelf
To fit the shelves:
1. Insert the runner into the slots in the side of the oven chamber, as shown in fig-
ures 1 and 2
2. Rotate the runner downwards by 90° so that the runner hooks into place and cre-
ates a level surface upon which the shelf can securely rest, as shown in figures 3
and 4
3. Repeat this process on both sides of the oven chamber
4. Slide the shelves onto the runners so that the spur is positioned on the underside
of the runner towards the back of the chamber (see figure 5). This will prevent the
shelf from tilting forwards when it is partially withdrawn
Figure 1:
Runner
Figure 2:
Runner inserted into slots in the side of
chamber
7

Figure 3:
Rotating runner into position
Figure 4:
Runner in position
Figure 5:
Shelf resting on runners with spur at rear of chamber
(highlighted in green)
Figure 6:
Shelves fitted
8

2.3 Flat Pack Stand (optional)
The flat pack stand is available in a range of sizes depending on the dimensions of the
product for which it has been ordered. Subsequently, the number of fixings may vary
between the different sizes of stand.
2.3.1 Parts Supplied
Stand Top (x1) Stand Leg (x2)
Stand Cross Brace (x2) M10 Bolt
M10 Washer M10 Locking Nut
9

2.3.2 Flat Pack Stand Assembly
10

2.4 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.
11

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.
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:
12

3.0 R38 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 Controller Operation
When switched on, the controller lights up, goes through a short test routine and then
displays the measured temperature and starts to control. The output light OUT1
indicates when heating is occurring.
To alter the setpoint, press the down arrow key once, “SPI” flashes. Then use the up
and down arrow keys to adjust the setpoint. Press the P key to accept.
3.3 R38 Over-Temperature Controller
When an R38 Controller is fitted to be used as an over-temperature controller, to
configure the setpoint:
lPress and hold the 'P' key until the display flashes 'SP'.
lPress the 'down' arrow key until the display shows 'AL'.
lPress the 'P' key to enable the setpoint option.
lUse the 'up' and 'down' arrow keys to select the required setpoint. The display will
flash between 'AL' and the setpoint value during this process.
lOnce you have input the required setpoint, press the 'P' key, followed by the 'U' key
to accept.
lThe display will flash 'AL' for 30 seconds before the setpoint is accepted.
Note that if the 'P' and 'U' keys are not pressed, the setpoint will be automatically
accepted after 30 seconds.
Over-Temperature Alarm
If the over-temperature alarm is tripped, then the 'OUT2' and 'AL' lights will illuminate
in the bottom right-hand corner of the controller.
13

Resetting the Over-Temperature
To reset the over-temperature controller, power cycle the product by turning the
instrument switch off, then on again.
3.4 Process Timer (if fitted)
To set a process time:
Press the P key; S.t1 shows momentarily on the display. The display then flashes. Use
the arrow keys to adjust the process time, which is in hours and minutes (hr.mn). Wait
5 seconds without pressing a key, or press the P key once, and the display returns to
normal.
To start the timer:
Press the U key once. Timing starts. The CNT light flashes slowly while timing is in
progress and the display counts down (at the end of each minute).
At the end of timing the OUT1 light comes on, the display flashes continuously and
power to the temperature controller is cut off.
To reset the timer after timing has finished:
Press the U key once. The timer is now idle; it is not stopping the oven from heating,
nor is it timing.
Power is only supplied to the temperature controller when the timer is reset or is
timing.
To stop the timer during timing, press U during the countdown. The temperature
controller remains on. It is not possible to resume timing. Pressing U again will reset
the timer.
3.5 Calibration
If the process requires an accurate temperature display it is possible to calibrate the
controller by entering a single temperature offset value as follows:
Please contact Carbolite Gero Service for detailed instructions on entering an offset in
the R38 Controller.
14

3.6 Over-Temperature Control (if fitted)
The over-temperature controller should typically be set at 15 °C above the main
controller. If an over-temperature condition occurs, check the main controller is
functioning correctly.
An over-temperature condition cuts off power to the heating elements. A light in the
over-temperature controller flashes. To reset this, refer to the over-temperature
control section of this manual.
3.7 Controller Replacement
If the over-temperature trip operates, a click occurs and a warning light near the
thermostat lights up; the reset button on the thermostat pops out. The reset button is
hidden behind the control dial. To reset the oven it is necessary to turn the thermostat
dial until the hole lines up with the reset button and press it using a small diameter
rod.
3.8 Temperature Controller Replacement
Before handling the controller: wear an anti-static wrist strap or
otherwise avoid any possibility of damage to the unit by static
electricity. Refer to the detailed instructions supplied with the
replacement controller.
Disconnect the product from the electrical supply and remove the cover (see section
6.0).
Make a note of all the wiring connections before disconnecting the wires. Loosen the
screw that holds the controller body clamp in place. Use a flat screwdriver or similar
object to ease apart the two plastic lugs on the side of the clamp and pull the
instrument forward out of the front control panel.
Reconnect the wires according to the notes made – or see section 8.0 for wiring details.
Note: If the product features an R38 over-temperature controller, then this should
be replaced using the same method described.
15

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.
This product has fan-assisted circulation; the fan is on when the instrument switch is
on.
Turn on the instrument switch to activate the temperature controllers. The controllers
illuminate and go through a short test cycle.
If a process timer is not fitted, the controller becomes illuminated and goes through a
short test cycle according to the controller setpoint or program. If a timer is fitted, the
controller may not become illuminated when the unit is switched on – to start the
controller, press the U button on the timer once (see section 0.1).
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.
Unless a process timer is fitted and is off, the product starts to heat up according to the
controller set point.
The product will heat up according to the controller setpoint or program, unless a time
switch is fitted and switched off.
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 The Oven Door and Chamber
It is recommended that the instrument switch is turned off if the oven door is to be
opened when the temperature is below 120 °C. If the door is opened when on and the
set temperature is below approximately 120 °C, then the controller will attempt to
compensate for the drop in temperature and the actual temperature may exceed the
set temperature when the door is closed again.
Please note that the fan is on when the instrument switch is on. Opening the door does
not switch off the fan.
The tip of the temperature sensor is visible on the right of the chamber, below the fan.
It is not electrically live, but it is delicate and should not be touched.
4.3 Loading and Unloading the Chamber
Where accurate temperature control of the load is important, use the central part of the
chamber and distribute the load to allow free air circulation. Do not place loads on the
chamber floor; use the bottom shelf.
16

Remember that the shelves and work pieces may be hot; use
suitable gloves or other handling equipment.
Have a heat-resistant surface available on which to place hot
materials.
There is no physical stop to prevent shelf removal; take care not to pull out a shelf
accidentally.
Additional shelves may be obtained from Carbolite Gero. The maximum load for each
shelf is 10 kg.
The maximum number of shelves and the maximum load for the oven are listed below:
model maximum number
of shelves
maximum load
per shelf
maximum load
for product
AX 120 8 10 kg 40 kg
4.4 Vents
On the back of the product are two vents, covered by a sliding baffle
plate. The inlet vent is permanently open, while the outlet may be
opened or closed by means of the sliding plate.
The sliding plate gets hot. Do not touch it when the product is hot. Make adjustments
when the product is cold.
4.5 Temperature Control
The temperature is controlled by an easy-to-operate digital unit. The oven temperature
range is from 40 °C to 250 °C, though the minimum temperature may be higher if the
ambient temperature is above 30 °C.
A matching digital timer is available to order, or may be retro-fitted. A second option is
an over-temperature control device. There is also the option of a locking handle.
Temperature accuracy is enhanced by the use of a Type K thermocouple as the
temperature control sensor. A simple air-flow adjustment may be made by movement
of a sliding vent control mounted at the back of the oven. Typical air-flow with the vent
open is 1850 litres/ hour at 100 °C, giving exchanges in chamber volumes per hour of
65 (AX 30), 28 (AX 60) or 14 (AX 120).
4.6 Explosive Vapours
Unless your product includes the stoving and curing option, this
model is not suitable for drying or heat treatment applications where
vapours are released that are combustible or which can form
explosive mixtures with air. Carbolite Gero manufactures other
products suitable for these applications.
17

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
Door Seal Visual inspection - check for splits or
fraying
Door Seal Replacement
Air Vent Check and clean if necessary
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, fre-
quency dependent on the standard
required
Operational Check Check that all functions are working
normally
Operational Check Thorough inspection and report incor-
porating a test of all functions
18

Performance
Cooling Fans (if fitted) Check whether the cooling fans are
working
Circulating Fan
(if fitted) Visual check to see if it is running
Circulating Fan
(if fitted)
Check bearings and replace if neces-
sary
Element Circuit Electrical measurement
Power Consumption Measure the current drawn on each
phase / circuit
Shelves Visual check for fit and damage
19

5.2.1 Cleaning
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.
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.
5.3 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.
5.4 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 a control sensor, a solid state relay, an element or set of elements,
a door seal and a fan kit (fan and motor assembly). Individual spare kits are also
available.
When ordering spare parts please quote the model details as requested above.
5.5 Retrofit Kits
Kits for process timer, over-temperature and locking handle are available. Instructions
for fitting these are supplied with the kits.
20