NeoDen IN12 User manual

Zhejiang NeoDen Technology Co., Ltd.
User Manual V1.1
Reflow Oven NeoDen IN12
Power saving
with built-in smoke filtering system
With smart temperature curve testing system
Easy operation

Content
1. Brief Introduction ............................................................................................2-3
2.Specification .....................................................................................................4-4
3.Main Parts......................................................................................................... 5-6
3.1 Reflow Oven Main Body........................................................................ 5-5
3.2 Operating Panel....................................................................................... 5-5
3.3 Cover and heating zone...........................................................................6-6
4.Installation Instruction.....................................................................................7-11
4.1 Power Supply Connection.......................................................................7-7
4.2 Installation Attentions............................................................................. 7-7
4.3 Status of Indicators..................................................................................8-8
4.4 Operation instructions........................................................................... 8-11
5. Temperature wave setting principle............................................................. 12-18
5.1 The reflow soldering theory and the temperature wave......................12-12
5.2 The set of the temperature wave......................................................... 12-18
6. Details about temperature area setting......................................................... 18-18
7. Temperature measurement method.............................................................. 19-19
8. Both side soldering instruction.....................................................................19-19
9. Trouble shooting.......................................................................................... 19-23
9.1 Soldering analysis............................................................................... 19-20
9.2 Precautions.......................................................................................... 20-21
9.3 Machine maintenance..........................................................................21-23

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Attention！Please read the user manual carefully before operating this machine.
1. Introduction
IN12 is a newly designed and manufactured reflow oven by NeoDen Tech. It has 12
temperature zones, unique heating module design, intelligent control system, built-in
soldering smoke filtering system, which makes it intelligent, innovative, compact and
high-performance.
Features
1. Built-in soldering smoke filtering system, effective filtration of harmful gases,
elegant appearance and eco-friendly, more in line with the high-end use
environment.
2. The control system has features of high integration, timely response, low
failure rate and convenient maintenance.
3. The unique design of heating module has the characteristics of high
temperature control accuracy, uniform temperature distribution in the thermal
compensation area, high thermal compensation efficiency and low power
consumption.
4. Hot air convection, excellent soldering performance.
5. High-performance aluminum alloy heating plate instead of heating pipe, both
energy-saving and high-efficient, and transverse temperature deviation is
significantly reduced compare to the similar reflow oven products in the
market.
6. Heat insulation protection design, the casing temperature can be effectively
controlled.
7. Smart control with high sensitivity temperature sensor, the temperature can be
effectively stabilized.
8. Intelligent, the custom developed intelligent control system, easy to use and
powerful.
9. Professional and unique 4-way board surface temperature monitoring system,
can give timely and comprehensive data feedback in actual operation, which
can effectively cope with any complex electronic products.
10. 40 working files can be stored for an easy loading during the working process.
11. PCB soldering temperature curve can be displayed based on real-time
measurement.
12. Lightweight, miniaturization, professional industrial design, flexible
application site, more user-friendly.

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13. Energy saving, low power consumption, low power supply requirements, the
ordinary civil electricity can meet the use. Compared with similar products in
the market, the electricity costs that this machine can save for you within one
year, enables you to purchase your second IN12.
14. The custom-developed stainless steel B mesh belt is durable and wear-resistant.
Not easy to deform after long time using.
15. Beautiful and elegant indicator design with red, yellow and green alarm
function.
16. Custom-developed drive motor based on the characteristics of the B mesh belt
to ensure uniform speed and long life.
17. 17 .The mesh sprocket made of high-precision profile technology and the
unique support structure can effectively reduce the vibration of the PCB in the
reflow zones, and easily cope with the soldering of small size components
such as 0201 and complex chips such as BGA/QFP/QFN.
18. The cooling zone with independent circulating air design completely isolates
the influence of the external environment on the internal temperature
chambers.
19. The optimized soldering fume filter systems tested by the dedicated airflow
simulation software can filter harmful gases as well as ensuring IN12 can keep
room temperature, reducing heat loss and reducing working power
consumption.
20. The unique heating plate design effectively ensures IN12 will cool down
evenly once the heating is stopped, and effectively prevents the deformation
and damage caused by the rapid temperature drop
21. The internal thermostat is made of stainless steel, which is environment
friendly and has no peculiar smell. The inner sides are equipped with
insulation cotton to effectively prevent heat loss.
22. Hidden screen design is convenient for transportation, easy to use.
23. The control system adopts imported chips, and the temperature control
accuracy reaches ±0.5%.
24. Adjustable wind speed in all heating zones and cooling zones, easily coping
with various soldering requests.
25. The upper temperature cover is automatically limited once opened, effectively
ensuring the personal safety for the operators.
26. Exclusively designed PCB guide device to realize the direct connection
between the mesh chain and the conveyor.

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2. Specification
Model
NeoDen IN12
Heating Zone Quantity
Upper6 / Down6
Cooling Fan
Upper4
Controller
VGUS Microcomputer
Transmission
Mesh Chain Drive
Heating Type
Nichrome Wire & Aluminum Alloy Heating
Conveyor Speed
50～600 mm/min
Temperature Range
Room temperature～300℃
Temperature Accuracy
1℃
PCB Temperature Deviation
±2℃
Max Soldering Width (PCB Width)
350mm
Length Process Chamber
1354mm
Heat-up Time
30 min
Max Soldering Height (mm)
35mm (includes PCB thickness)
Operation Direction
left→right
Electricity Supply
AC 220v/single phase
Starting Power
2.4kw～4.8kw (adjustable)
Typical Working Power
approx. 2kw(1.5mm fiberglass PCB )
Machine Size
L2300mm×W650mm×H1280mm
Packing Size
L2420mm×W730mm×H1430mm
Net Weight
300KGS
Gross Weight
383KGS

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3. Main Parts
3.1 Reflow Oven Main Body
3.2 Operating Panel

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3.3 Cover and Heating Zone
3.31 Heating Zone

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4. Installation Instruction
4.1 Power Supply Connection
IN12 power connection is single phase 220V, please connect it against local users
actual situation. Connection as below picture: Open the cover on bottom right corner,
L stands for the live wire, N stands for the zero wire, and E stands for the ground wire,
connect to the 220V power supply. According to the wiring requirements, the L
should be connected to one live wire, and the N should be connected to one zero wire;
the E should be connected to one ground wire properly.
4.2 Installation Attentions
♦ Put down the bearing foot cup, level it and then connect it to the power supply,
voltage requirement 220V；
♦ The electricity wire need no less than 2.5mm2, it’s better to directly use 4mm2(If
2.5mm2, then it can only connect with one set of IN12 Reflow oven, other equipment
Will not be allowed to connect together.
♦ The machine should be set in standard SMT workshop, stay away from flammable
and explosive if couldn’t meet previous requirements.
♦ Exposed wire harness should be well protected, prohibit to expose at the passage or
flue in case of causing any accident.
E N L
Air switch
RCD (Leakage
protector)
Wire
connection

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4.3 Status of Indicators
There’s tri-color light on top of the cover, it is used to indicate whether all zones’
temperature have reached the well-set temperature. When all temperature reach
to well-set temperature, indicator light up green; While in the heating-up status,
indicator will flash as yellow; Only when the temperature zone is closed (without
flash) or in any faulty (in flash status), it will show as red .
4.4 Operation instructions
♦ Power on
Switch the button to ON status, machine start up. Please check the emergency button,
air switch and RCD before power on the machine.
♦ Chain mesh speed setting
Click the speed parameter,a blank parameter dialog will pop out, type into the
temperature you need set. Generally suggestion 250-300mm/min (Remarks:
temperature will also be influenced once chain speed changed, please re- test the
temperature curve and adjust temperature according to the test result)
♦ Temperature setting
As above picture showed, data on upper side is well-set temperature from zone1 to
zone6; data in the middle is the real-time temperature. Click the temperature parameter
dialog, directly type into the set temperature, the heating zone will start heating and
keep it in a stable situation while temperature reached.
Setting Transport
speed setting
Set temperature
Real-time temperature
Real-time status
Real-time power
Power on/ off
Emergency
Zone power on/ off

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♦Save and use of soldering formula
♦Save method: Click ‘SAVE AS’ on the main control page or click the file list page on
the left to enter the file management page. Select the location you want to save (the
file list box will turn green when selected). Click the SAVE button to save the current
used formula and file name at the same time, there will be a beep after success.
♦How to modify the file name: select a location to be stored in the file list. At this time,
the file name in the file list box will be updated to the text box of the file name. Click
the text box of the file name to pop up the input keyboard. After filling in the required
name, click OK, and then click the Save button. After success, there will be a beep.
♦Usage: select the required file and click the load button. After success, there will be
a‘beep’ sound.
♦Fan management
Click the Fan Control button in the lower right corner to enter the management page.
Drag the adjustment button to adjust the required wind speed. The default value is 100.
HOT1-HOT6 is the hot wind speed of 1-6 temperature zone, COOL is the wind speed
of cooling zone.
Text box
File List

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♦File generation Wizard
(Note: due to the great difference in complexity of each product, the temperature
parameters generated are only used as reference. In order to achieve the best solder
effect, it is necessary to measure the temperature curve and improve the parameters
after comparing with the temperature curve provided by the solder paste manufacturer.)
Step 1: select the type of solder paste to solder the product. If the model is not found in
the list, please go to search in the appendix, or ask the solder paste manufacturer about
the melting point, and then select the option with the closest melting point.
Step 2: select the material and thickness of PCB to be soldered.
After selection, the system will automatically generate the corresponding soldering
formula.

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♦Temperature curve
Connect the Temperature sensor to the SENSOR CONNECTOR, attach the sensor
to PCB, and then click "start" button in the curve setting interface after PCB is put
into the oven to get the temperature curve, click "stop" to pause the generation of
temperature curve, and click "clear" to clear the temperature curve record. The "red,
green, yellow and blue" sub table represents the real-time temperature of sensor on
four interfaces corresponding to the same color.
♦Power off
Click the temperature zone switch on the main control page to close the temperature
zone. Turn the switch to the off position, and the machine will turn off.
Real-time
temperature
Temperature sensor
connector

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5.Temperature wave setting principle
5.10 what is the heating unit temperature?
the real-time temperature of the heating plate.
5.11 what is oven temperature?
the air temperature between the chain surface and the heating plate.
5.12 what is PCB surface temperature?
the temperature of component soldering feet when PCB is soldered. (the guide
temperature on the soldering wave provided by the solder paste manufacturer
refers to the PCB surface temperature.)
When working, the temperature displayed in the temperature zone on the panel is
the actual temperature of the heating unit, which does not represent the temperature
in the oven and the actual temperature of the plate surface. Therefore, the
temperature displayed will be about 20-40 degrees higher than the temperature in
the oven. The actual use is related to the chain speed, PCB size, thickness, material
and component density.
5.1 Principle of reflow soldering and temperature wave
When the PCB enters the heating zone (dry zone), the solvent and gas in the solder
paste evaporate. At the same time, the flux in the solder paste moistens the pad,
component ends and pins. The solder paste softens, collapses and covers the pad,
isolating the pad and component pins from oxygen. When the PCB enters the heat
preservation area, the PCB and components are fully preheated to prevent the
damage of PCB and components caused by the rapidly raise of temperature.When
the PCB enters into the soldering area, the temperature rises rapidly to make the
solder paste melt. The liquid soldering tin enters the cooling area to solidify the
solder joint and complete the reflow soldering. The temperature wave is the key to
ensure the soldering quality. The temperature rise slope and peak temperature of
the actual temperature wave and the solder paste temperature wave should be
basically consistent. Before 160 ℃, the heating rate should be controlled at about
1℃/ s. if the heating rate is too fast, on the one hand, the components and PCB
will be heated too fast, which will damage the components and easily cause PCB
deformation; on the other hand, the solvent in solder paste will volatilize too
quickly, which will easily splash metal components and produce solder balls. The
peak temperature is generally set at 20 ℃- 40 ℃higher than the melting
temperature of solder, and the reflow time is 10s-60s. If the peak temperature is
low or the reflow time is short, the soldering will not be sufficient, and in serious
cases, the solder paste will not melt; if the peak value is too high or the reflow time
is long, it will cause metal powder oxidation, affect the soldering quality, and even
damage the components and PCB.
5.2 Setting of temperature wave
Set according to the temperature wave of solder paste and the soldering principle
provided above. Solder paste with different metal content should have different
temperature wave, and the reflow temperature wave should be set according to the
temperature wave provided by the solder paste manufacturer. In addition, the
temperature wave is also related to the density and size of the heated PCB and

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components.
An optimized reflow temperature wave is one of the most important factors to
obtain high quality solder joints in printed circuit board (PCB) assembly using
surface mount components. The temperature wave is a function of the temperature
applied on the circuit assembly to time. During the reflow process, it represents the
temperature at a specific point on the PCB to form a wave at any given time.
Several parameters affect the shape of the wave, the most important of which is the
belt speed and the temperature setting of each zone. The belt speed determines the
duration of exposure of the board to the set temperature of each zone. Increasing
the duration allows more time for the circuit assembly to approach the temperature
setting of the zone. The total duration of each zone determines the total processing
time.
The temperature setting of each zone affects the temperature rising speed of PCB,
and high temperature produces a large temperature difference between PCB and
zone temperature. The set temperature of the increase zone allows the board to
reach the given temperature faster. Therefore, it is necessary to make a figure to
determine the PCB temperature wave. Next is the outline of this step to generate
and optimize the graphics.
The following equipment and Auxiliary tools are required before starting the wave
procedure
High precision temperature profiler ( with IN12), thermocouple (with IN12), tools
for attaching thermocouple to PCB (mainly high temperature tape) and solder paste
parameter table.
There are several ways to attach thermocouple to PCB. The better way is to use
high temperature solder such as silver / tin alloy, and the solder joint should be as
small as possible.
Another acceptable method is fast, easy, and accurate enough for most applications.
A small amount of thermal compound (also known as thermal paste or grease,
which is often used on computer CPU or graphics card CPU) spots cover the
thermocouple, and then stick it with high-temperature tape (such as Kapton).
Another way to attach thermocouple is to use high-temperature adhesives, such as
cyanoacrylate adhesives. This method is usually not as reliable as other methods.
The attachment position should also be selected. It is usually better to attach the
thermocouple tip between the PCB pad and the corresponding component pin or
metal end.
(Figure 1. Attach thermocouple tip between PCB pad and corresponding
component pin or metal end)
The table of solder paste characteristic parameters is also necessary, and the
information contained in it is very important to the temperature wave, such as the
desired duration of temperature wave, the active temperature of solder paste, the

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melting point of alloy and the desired maximum temperature of reflow.
Before you start, you must have a basic understanding of the ideal temperature
wave. Theoretically, the ideal wave consists of four parts or sections, the first three
regions are heated and the last one is cooled. The more the temperature zone of the
oven, the more accurate and close the profile of the temperature wave can be
achieved. Most pastes can be successfully reflowed with four basic temperature
zones.
(Fig. 2. Theoretically, the ideal reflow wave consists of four zones, the first three
zones are heated and the last zone is cooled.)
It is also used to warm up the ambient temperature of the PCB from the active zone.
In this region, the temperature of the product rises continuously at a rate of no
more than 2-5℃per second
If the temperature rises too fast, it will cause some defects, such as tiny cracks in
ceramic capacitors. If the temperature rises too slowly, the solder paste will feel
too much temperature, and there is not enough time for PCB to reach the active
temperature. The preheating zone of the oven generally accounts for 25 ~ 33% of
the total length of the heating channel.
The active area, sometimes called dry or wet area, generally accounts for 33 ~ 50%
of the heating channel, and has two functions. The first is to sense the temperature
of PCB at a relatively stable temperature, allowing components of different quality
to be homogeneous in temperature, so as to reduce their considerable temperature
difference. The second function is to allow the flux to be activated and volatile
substances to volatilize from the solder paste. The general active temperature range
is 120 ~ 150℃. if the temperature of the active zone is set too high, the flux does
not have enough time to activate, and the slope of the temperature wave is an
upward increasing slope. Although some solder paste manufacturers allow some
temperature increase during activation, the ideal wave requires a fairly stable
temperature so that the PCB temperature is equal at the beginning and end of the
active zone. Some ovens on the market can not maintain a flat active temperature
wave. Choosing a oven that can maintain a flat active temperature wave will
improve the weld performance, and users will have a larger processing window.
The reflow zone is sometimes called the peak or final heating zone. The function
of this area is to increase the PCB assembly temperature from the active
temperature to the recommended peak temperature. The activation temperature is

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always lower than the melting point of the alloy, and the peak temperature is
always at the melting point. The typical peak temperature range is 205 ~ 230℃. if
the temperature is set too high in this area, the temperature rise slope will exceed 2
~ 5℃per second, or the reflow peak temperature will be higher than recommended.
This situation may cause excessive crimping, delamination or burning of PCB, and
damage the integrity of components.
Today, the most commonly used alloy is Sn63 / Pb37, and this proportion of tin
and lead makes the alloy eutectic. Eutectic alloy is an alloy that melts at a specific
temperature. Non eutectic alloy has a melting range, not a melting point,
sometimes called plastic loading. All the examples described here refer to eutectic
tin / lead, which has a melting point of 183℃, because it is widely used.
The ideal cooling zone wave should be a mirror image of the reflow zone wave.
The closer to this mirror relationship, the closer the solid structure of solder joint is,
the higher the quality of solder joint is and the better the integrity of solder joint
is.
The first parameter to be considered for the temperature wave is the speed setting
of the conveyor belt, which will determine the time spent in the heating channel of
the PCB. Typical solder paste factory parameters require a heating wave of 3-4
minutes. Dividing the total heating channel length by the total heating temperature
sensing time is the accurate belt speed. For example, when the solder paste requires
four minutes of heating time, using six feet of heating channel length, the
calculation is: 6 feet ／4 minutes = 1.5 feet per minute = 18 inches per minute.
Next, it is necessary to determine the temperature setting of each zone. It is
important to understand that the actual interval temperature is not necessarily the
display temperature of the zone. The display temperature only represents the
temperature of the thermocouple in the area. If the thermocouple is closer to the
heating source, the displayed temperature will be relatively higher than the interval
temperature. The closer the thermocouple is to the direct channel of PCB, the
displayed temperature will be more able to reflect the interval temperature. It is
advisable to consult the oven manufacturer to understand clearly the relationship
between the displayed temperature and the actual interval temperature. In this
paper, the interval temperature rather than the display temperature will be
considered. Table 1 lists the interval temperature settings for typical PCB assembly
reflow.
Table 1. Typical PCB return zone temperature setting
I n t e r v a l
Interval temperature setting
Actual plate temperature at the end of interval
Preheating
210℃
140℃
Activity
177℃
150℃
Reflow
250℃
210℃
The interval temperature is set to the actual plate temperature at the end of the
interval
After the speed and temperature are determined, they must be input to the oven
controller. Once all parameters are input, start the machine, and after the oven is
stable (i.e., all the actual displayed temperatures are close to the set parameters),
the wave can be started. The next PCB is placed in the conveyor belt, which
triggers the thermometer to start recording data.
For convenient using,some thermometer includes a trigger function to
automatically start the thermometer at a relatively low temperature, which is
typically slightly higher than the human body temperature of 37°C (98.6°F). For

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example, the automatic trigger of 38°C (100°F) allows the thermometer to start
working as soon as the PCB is put on the conveyor chain and into the furnace, so
that the thermocouple will not be triggered by mistake when it is handled by the
human.
Once the initial temperature profile is generated, it can be compared with the
profile recommended by the solder paste manufacturer or the profile shown in
Figure 2.
First, it must be verified that the total time from the ambient temperature to the
peak temperature of the reflux is compatible with the desired stay time of the
heating curve. If it is too long, increase the conveyor speed proportionally; if it is
too short, decrease the conveyor speed proportionally.
In the next step, the shape of the temperature profile must be compared with the
desired one (Figure 2). If the shape is not compatible, then compare it with the
following figures (Figures 3-6). Choose the most compatible temperature profile
compared to the actual shape of the profile. Should consider the deviation from left
to right (process sequence). For example, if there is a difference between the
preheating and soldering zones, first adjust the difference in the preheating zone
correctly. Generally, it is best to adjust one parameter at a time and test in run
before making further adjustments.Because a change in a given zone will also
affect the results of subsequent zones. We also recommend that novices had better
make small adjustments. Once you gain experience on a particular oven, you will
have a better "feel" to make more big adjustments.
Figure 3:Preheat too much/little soldering profile

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Figure 4:Set too high/low temperature of active zone
Figure 5:Soldering too much/little

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Figure 6:Cooling too much/little
When the final temperature profile is as close as possible to the desired profile, tke
record or store of the parameters for later use. Although this process is slow and
laborious at first, it can eventually gain proficiency experience, resulting in high-
efficiency production of high-quality PCBs.
6. Temperature profile setting method
♦Set the temperature of each zone and the speed of the conveyor chain from the initial
value. For cold oven, preheat for ~30 minutes.
♦After the preheating is completed, let the PCB go through the heating soldering
system. If soldering does not occur, the conveyor chain speed can be appropriately
reduced. Or on the premise of not changing the transmission chain speed,increase the
set temperature appropriately, and pay attention to not exceeding the bearing capacity
of the PCB and components when adjusting the set temperature.
♦Let the PCB go through the new conveyor chain under new speed or the adjusted set
temperature,if no soldering occurs,then do the adjustment of the previous step,
otherwise proceed to the next step to fine-tune the temperature profile.
♦The temperature profile can be adjusted appropriately according to the complexity of
the PCB.Can reduce the speed of the conveyor chain and increase the soldering time;
on the contrary, add the speed of the conveyor chain will reduce the soldering time.
♦Generally, when the PCB with components mounted on passes through the soldering
system but is not completely slodered, it can be properly adjusted and then put into the
soldering system for soldering again. Generally, it won’t effect on the PCB and
components.
♦The temperature setting is generally from low to high. If the soldering temperature
range exceeds the set temperature much, should increase the speed of the conveyor
chain or reduce the set temperature.
♦Different PCB boards have different heat transfer rates and heat absorption, then the
heating time and temperature required by soldering are also different. For double-layer
boards and multilayer boards and PCBs with more areas and pads, the setting
temperature is relatively higher , And for single-sided boards or paper plastic boards or

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different areas, the setting temperature of PCBs with few pads is correspondingly
lower. There is also a certain connection with the amount of boards released per unit
time. However, in normal production, the soldering machine has its own adjustment
system for general PCB board changes. The soldering machine can be used for normal
production at the recommended temperature during training, unless the heat absorption
of the PCB changes significantly.,then need do adjust accordingly.
7.Temperature Testing Way
♦Attach the temperature thermocouple sensor to a same or similar size PCB to observe
the soldering. Put the PCB to the conveyor chain,then generate the temperature
profile,compare to the recommended temperature profile. If it is same or similar to the
self-adjusting profile, then you can start production, otherwise, according to the
temperature profile, adjust the temperature control area to increase and decrease the set
temperature by about 5 degrees in large temperature difference area, or do
comprehensive adjustment of whole machine to get a temperature profile that can be
used for production work.
♦When starting to put PCB or abruptly change the number of PCB, there is a
difference between the actual temperature and setting temperature. The difference
will turn to normal range when putting the PCB with constant speed for a while.
8. Double sided board soldering instruction
♦Use hot air reflow soldering can finish double-side component soldering. Double-
side soldering design means components are in double-side of the PCB need to
soldering. Double side soldering includes double-side soldering tin and single-side
soldering tin and another side drying glue, as for single-side soldering tin and
another side drying glue, it is easier. First, finish one side’s soldering tin as the
same as single-side, then finish another side tape glue drying in low temperature,
finish double-side SMT craft, after that carry on the next step plug-in or tin process
on craft. Double-side soldering is generally treated as below follows:
♦Start the reflow oven, set up the transfer chain speed controller, finish the A side
components reflow soldering with normal soldering craft.
♦Upend the PCB, repeat normal procedure to mount the component, adopt top
heating strategy to let the B side reflow soldering, but the upend A side has been
reflow soldering, the compounds in thick liquid volatilize, the melting point of tin
is higher than the solder paste, which in order to keep the A side components not
fall out.
9. Trouble shooting
9.1 Soldering analysis
Problem
Possible causes
Solutions be available
Incomplete
reflow
Inadequate heating
lower the transfer chain speed
Shadows from components
a. Increase the transfer chain speed
b. Increase bottom heat
Due to the middle layer of copper foil
Decrease transfer chain speed and increase
temperature
Inadequate
moist
PCB, components without enough solder
paste
Pre-paste to components and PCB
No enough moist time
Increase the temperature of heating zone
PCB bend
Exceeding upper and lower temperature
difference limits
Reduce temperature difference between
preheating zone and bottom temperature zone
Increase transfer chain speed
PCB
discoloration
Exceeding tin temperature on the board,
exceeding temperature gradient or
Increase transfer chain speed
Decrease the preset zone temperature