Naturela NPBC-V3C-B User manual

Controller for pellet oven – NPBC-V3C-B
Controller for pellet oven
or hot air generator
NPBC-V3C-B
SOFTWARE VERSION 40/1
User Manual / ver 3.7 http://www.naturela-bg.com/en/ page 1 of 30

Controller for pellet oven – NPBC-V3C-B
CHANGES IN MANUAL F R THE W RK AND THE S FTWARE F THE C NTR LLER
User
Manual
version
Changes Page
3.2 •Software version amended to 27/14.
•New way of dismissing the alarms for registered problems. Most of them
are automatically dismissed as soon as the reason for them is no longer
present. Alarms caused by more serious events require manual dismissal by
pressing the left navigation button "◄" for more than 2 seconds.
•New appearance of the "Information" screen and the "Equipment" menu
1
11
16
17
3.3 •Software version amended to 2 /14.
•Alphabetical order of the languages: Bulgarian, English, Latvian, Portugal
and Spanish.
•Added option to work with additional "Control module" with room
thermostat functions NRC-6 SV
3.4 •Software version amended to 31/15.
•In case the burner is currently off (due to reached set temperature, for
instance), but it is about to turn on and if there is a timer scheduled to turn it
off in 10 minutes or less, the burner will remain off, because otherwise the
extinguishing procedure may begin before the fire is stabilized.
•If OD input activates during Ignition or Unfolding procedures, the
extinguishing procedure begins only after switching to any of the power
levels.
3.5 •Software version amended to 32/16.
•If the burner is on and timers are active, holding the On/Off button for more
than 2 seconds deactivates the timers.
•Loading first dose time increased to 240 seconds
•Version screen displays software and hardware version of the controller, as
well as WiFi modem's software version if it is 24 or higher
17
15
3.6 •Software version amended to 34/16.
•Main auger’s capacity increased to 350 kg/h.
•Consumed pellets graphic's scales increased to 5, 10, 20, 40, 0 and 160
kg / h
•Minimum value for ignition/extinction level of illumination set to 1
•Ignition's level of illumination value must be higher than extinction's.
•Added Russian language.
3.7 •Software version amended to 40/1
•Switch mode choice between Standby, On and Timers
•New menu in User settings for fuel selection
User Manual / ver 3.7 http://www.naturela-bg.com/en/ page 2 of 30

Controller for pellet oven – NPBC-V3C-B
INTR DUCTI N
NPBC-V3C-B is a new updated version of the popular controller NPBC-V3M-1. It works with a
new Control module with a color TFT display NRC-6 and NPBC-V3M Executive module. This
model's most important advantages are:
•Clearer and intuitive user interface with modern looking menus and 6 control buttons.
•Additional warning messages about incorrect parameter input or if parameters from a different
menu require corrections after the current changes.
•The Control module can be equipped with a WiFi module NRM-W3 for connection with the
Naturela remote monitoring and control system through the web
•4 preset fuel profiles make switching between different fuels easier than ever
•Statistical information about the fuel consumption divided by hour and based on a calibrating
constant parameter for the fuel auger's capacity.
•A list with short description, date and time of the occurred errors and any other event
concerning the controller's work.
•More parameters about the burner's work and current state displayed on the main screen at the
same time
•A micro USB coupling on the face panel of the Control module for connection with a computer
with software for direct control and monitoring.
The controller NPBC-V3C-B is designed to run burners, which use a photo sensor to detect the
burning fire. The pulsing control of the auger motor from the pellet tank allows the precise dosing of
the amount of pellets that goes to the burner. NPBC-V3C-B can control an optional internal auger
motor that forwards the pellets inside the burner. The controller runs two blowers: one that provides
the air to the burning chamber and the other is an additional fan, for example, for taking out the
exhaust gases from the boiler, if necessary. Both blowers' power can be adjusted from the controller.
NPBC-V3C-1 has an option to measure and control the temperature of the exhaust gases with a high
temperature sensor pt100, mounted in the entrance of the vent. For more effective cleaning process the
controller can also run an additional powerful fan to blow away the ashes from the burning chamber or
a mechanical cleaning mechanism with an option to be run by one controlling or powering up voltage.
All of the controlled mechanisms must work on 220VAC or 110VAC mains power supply!
User Manual / ver 3.7 http://www.naturela-bg.com/en/ page 3 of 30

Controller for pellet oven – NPBC-V3C-B
MECHANISMS AND SENS RS C NTR LLED BY NPBC-V3C
Electric feed screw motor to transfer the fuel from the bunker to the burner (power up to
1 0W)
Electric internal auger motor to forward the fuel to the burning chamber (power up to 1 0W)
Main blower with smooth speed control to regulate the air flow (power up to 1 0W)
Additional cleaning fan (power up to 900W)
Exhaust gases fan with smooth speed control (power up to 1 0W)
Heating element to fire the pellets (power up to 00W)
( ptional) Analog output for frequency inverter to power up a powerful air fan
Photo sensor to detect the burning fire
Temperature sensor or thermostat to control the back burning
High temperature pt100 sensor to control the temperature of the oven or hot air.
A potential free contact of a room thermostat for better control of the burning process
according to the room temperature.
USB interface for connection with a computer
NPBC-V3C INPUTS AND UTPUTS DESCRIPTI N
Outputs Inputs
FM Main fan RT Room thermostat. To this input could be
connected a normally opened or
normally closed contact, with no
additional voltage.
FSG Fan for the flue gases PS Photo sensor
SF Screw for fuel RB Reverse burning sensor
SB Internal screw B
PH Heating installation pump WH Key for forced stop
PWH Hot water heater pump PT pt100 high temperature sensor to control
the temperature of the oven or hot air
IGN Ignition heater OD Key to force work phase suspend (Open
Door)
FC Fan for cleaning LED
ACF Analog controlled fan ( ptional)
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Controller for pellet oven – NPBC-V3C-B
User Manual / ver 3.7 http://www.naturela-bg.com/en/ page 5 of 30

Controller for pellet oven – NPBC-V3C-B
WAY F PERATI N
A burner controlled by NPBC-V3C-B can work in continuous automatic mode or in timer mode.
While in timer mode, the burner works only during the intervals of the day and the days of the week
set by the user. While working, it goes through several stages: cleaning, igniting, unfolding the fire,
modulated burning process according to the current and set temperature of the boiler, intermediate
cleaning performed during the burning process, extinguishing and cleaning again. The current stage of
the burner is displayed in green color on the bottom line of the main screen.
Every ignition begins with a cleaning cycle to clean all leftovers of the previous burning. At first only
the main fan works for as long as it is set in the menu Factory Settings → Burning Setup → Fuel X
→ Cleaning, line Start, column Fan. Then the Cleaning fan also starts and works for as long as it is
set in the same menu, line Start, column FC. The cleaning procedure is followed by the igniting
phase.
The ignition procedure starts with loading the first fuel dose in the burning chamber. The electrical
heater fires up the fuel while the fans provide the air flow. The procedure is performed in 3 stages.
During the first stage only the ignition heater works to reach the necessary temperature for ignition
faster. During the second and the third stages the ignition heater works along with the fans that provide
the necessary oxygen for the ignition and blow the heat from the heater to the fuel. It is recommended
to set lower speed for the fans during the second stage, so that they won't cool down and blow off the
flame and higher speed for the third stage to increase the air flow. To set the maximum duration of
each stage and the fans' speed go to the menu Factory Settings → Burning Setup → Fuel X →
Ignition. When the photo sensor detects the light from the burning fire, the ignition heater turns off
and the burner goes to Unfolding fire phase to stabilize the fire. If the pellets do not ignite during the
set time for this, the burner loads a new portion and makes a new attempt for ignition. This happens
only for the first 3 ignition retries and the pellet portion for each of them is respectively 100%, 50%
and 25% of the set dose. After the last attempt for ignition, the burner stops and displays an error
message for ignition fail. The parameters for the first dose and the ignition can be set in the menu as
many retries as set in the menu Factory Settings → Burning Setup → Fuel X → Ignition. The
parameters for detection of the burning fire can be set in the menu Factory Settings → Flame
Detection.
The successful ignition is followed by the smooth unfolding procedures. If the burner goes instantly to
burning on 3rd power level, when the fire is still unstable and the burning chamber is cold, the high air
flow from the fan might blow off or smother the flame. To avoid this, the burner waits for the first
dose of pellets to burn out and then slowly increases the power to the highest required power level
according to the temperature difference between the set temperature and the current temperature of the
boiler, starting with the lowest level P1. The parameters for the Unfolding fire process can be set from
the menu Factory Settings → Burning Setup → Fuel X → Unfolding Fire.
The next phase is the burning control. NPBC-V3C-1 has settings for 4 different power levels. Three of
them are used for the burner's normal work. The 4th power level maintains the burning fire to avoid
unnecessary cycles of extinguishing, cleaning and ignition when the water in the boiler has reached the
set temperature. Of course, if there is no need for more heat in the heating installation for longer period
of time, the burner turns off. The portion of pellets for each power level is a function of the auger
motor's capacity and activate time and the cycle between two of its turnings on. The parameters for
each power level's settings are auger motor's active time, cycle between two turnings on and main and
exhaust fans' speed. These parameters can be set in the menus Factory Settings → Burning Setup →
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Controller for pellet oven – NPBC-V3C-B
Fuel X → Setup P1/Setup P2/Setup P3/ Suspend. In the beginning of every feeding cycle, the burner
automatically chooses the best power level depending on the difference between the set and the current
temperature of the boiler. The temperature difference for each power level, the maximum time for
maintaining the fire (Suspend power level) as well as the maximum temperature for overheating can be
set in the menu Factory Settings → Power Modulation. If the maximum time for Suspend power
level runs out or if the temperature of the boiler gets higher with as many degrees as set for
overheating, the burner turns off. While in Suspend mode, if the temperature difference reaches the set
value for any of the power levels and if there is still embers in the burning chamber, the burning
process resumes directly to the necessary power level.
The burner turns off because of several different reasons: automatically – because of no need of heat
anymore, or by timer, or because of an error that requires it to turn off (for example, Back burning), or
manually – from the Turn On/Off button or from a switch connected to the WH input. No matter the
reason or the way, the burner always performs the same extinguishing procedure. During the
extinguishing phase the fuel feeding stops and the fan keeps working slowly to help the last remained
pellets to burn out and to prevent back burning to the pellet bunker. When the photo sensor detects that
the fire is off, the burner goes to cleaning phase and after that in initial state.
During the cleaning phase the main fan works on 100% of its power. If there is an additional powerful
cleaning fan or mechanical cleaning system, connected to the FC output, it turns on, too. The settings
for cleaning before ignition, after extinction and in case of a problem are different. The procedure is as
follows:
1. The burner turns off.
2. The main blower turns on and works on maximum power for as long as it is in the menu
Factory Settings → Burning Setup → Fuel X → Cleaning, column Fan
3. After the above time is up, the additional powerful fan or the mechanical cleaning system
connected to the FC output turns on and works along with the main blower for as long as it is
set in the menu Factory Settings → Burning Setup → Fuel X → Cleaning, column FC
Besides the cleaning on start, stop and in case of alarm, the controller has an option for an automatic
cleaning procedures, which can be set from the menu Factory Settings → Burning Setup → Fuel X
→ Cleaning. During these procedure the burner turns off, performs the procedure for Cleaning on
Stop and then turns on again.
As an additional cleaning method, some of the ashes from the burning process can be blown away
during the intermediate cleaning procedures that are performed while the fire is burning. During the
intermediate cleaning the FC output activates and/or the main and the exhaust fans' power can be
increased. The parameters for this procedure are: cycle for the procedure to repeat, duration of the
cleaning, fans' speed during the intermediate cleaning and whether the FC output will be active or not.
During this cleaning method the pellet feeding doesn't stop.
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Controller for pellet oven – NPBC-V3C-B
EXPL ITATI N INSTRUCTI NS
NPBC-V3C-1 Control module has 6 buttons to navigate through the menus:
Controller's main screen appears shortly after turning the power supply on:
Animations on the main screen indicate when any of the auger motors or the main fan is currently
active. An animated flame in the boiler is a real time indication for the burning fire, detected by the
photo sensor. The messages on the bottom line of the screen appear in different colors depending on
the type of information they provide: white text for the date, green for the current work phase and red
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Time
Boiler's water temperature
External stop activated
(OD input)
Heating element ON
Customized
information fields
Status bar with icons for the
outputs' current state and
the Internet connection
Main fan's speed
Fuel type
Date,
burner's work phase (table 1)
or registered errors (table 2)
Menu / Enter ( )
Arrow navigation buttons
with different functions
depending on the current menu
On / Off
Micro USB

Controller for pellet oven – NPBC-V3C-B
for errors. If several messages are to be displayed at the same time, they switch on every 4 seconds.
The time must be set correctly for the burner to function properly. If it hasn't been set yet, its
indication is --:--.
Most of the error messages that appear in red at the bottom of the main screen are indicated
by a three-toned sound signalization. In some cases the error message disappears soon after
the problem is resolved. Ho ever, there are some errors that if occur, remain on the screen
until the user dismisses them manually. Examples for such messages are “Back burning”,
“Boiler Frost”, etc. They can be cleaned only by holding the left navigation button ( ◄ )
pressed for 2 seconds, hile on main screen
Customized information fields could display any of the following parameters:
Icon Displayed information
Level of illumination, measured by the photo sensor.
Exhaust fan's speed
Information about the upcoming action of the timer. If there are no active
timers or the burner is in Standby mode, there is no information under the
icon. If there is at least one activated timer and the burner is ON, regardless
of the fuel type, the upcoming action (On/Off) and the time for it (or the
day of the week if it is after 23:59 pm on the current day) are displayed
under the icon.
Current calculated power of the burner. A calibrating constant parameter
for the auger motor's capacity must be set to assure the correct value of the
burner's power. The calibrating constant is available in the menu Factory
Settings → General Settings → Feeder capacity
Status bar icons description:
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Internet connection
Active room thermostat Active FC output
Active open door key

Controller for pellet oven – NPBC-V3C-B
How to turn the burner on/off:
Press the On/Off button to enter the switch mode menu:
Press the up or down navigation buttons (▲ or ▼) to select a row and confirm your choice by
pressing the On/Off button. To abort your choice and return to the main screen press the left navigation
button (◄) or press no buttons for more than 5 seconds. The field “Fuel type” on the main screen
shows the currently selected fuel that the burner is set to burn. If this field is missing, the burner is
either off or is about to turn off. The most certain indication that the burner is off is that there is no
green text on the bottom line with any of the work phases from table 1.
Table 1
Work phase Work phase
1Cleaning 6Power level P1
2Feeding 7Power level P2
3Ignition Power level P3
4Unfolding fire 9Intern Clean
5Suspend 10 Extinguishing
While in Standby mode, the burner doesn't work. If it was working right before switching to this mode,
it will instantly start the extinguishing procedure. It needs some time to completely put down the fire
and to perform the Cleaning on Stop procedure. The burner's and the boiler's aggregates might still
work for some time during the Standby mode.
The installations' circulation pumps keep orking until the conditions for them to ork are fulfilled,
even if the burner is off, thus ensuring the maximum usage of the heat energy.
The Fuel type field appears on the screen right after the burner is on. Then the Cleaning on Start
procedure and the ignition start if all of the necessary conditions are fulfilled: the temperature of the
boiler is lower than the set temperature, the room thermostat and the WH input for external stop switch
are not activated, there are no error messages or activated timers that require the burner to stay off. All
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Currently selected row

Controller for pellet oven – NPBC-V3C-B
of the work phases (Cleaning, Ignition, Unfolding fire, Power modulation, Suspend mode and
Intermediate cleaning) are executed according to the set parameters for the currently selected fuel type.
While in Timers mode, the burner works only during the time intervals when its work is allowed.
These time intervals can be set from the menu Timers in User Settings. If Timers mode is selected, but
there are no active timers set, the burner remains off and a warning message is displayed on the screen.
As soon as any of the timers is activated, the burner will switch to Timers mode automatically:
How to change the set temperature for the boiler
Press the up or down navigation buttons (▲ or ▼) while on main screen to enter the Set Temperature
menu. Press the up or down navigation buttons again to change the value in the relevant direction.
Hold the button to change the value with 5°C per second. Press the button  (Menu) to save the
changes and return to the main screen or press no buttons for 5 seconds to exit the menu without
saving.
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Controller for pellet oven – NPBC-V3C-B
Additional information and statistics
While on main screen, press the right navigation button (►) to access the additional information and
statistics screens.
Statistics charts about the pellet consumption
The first group of information screens is about the pellet consumption. Press the up or down
navigation buttons to browse the charts for the last 4 days, starting with the current day. The horizontal
axis of the full screen histogram is equally divided for 24 hours and the vertical axis represents the
consumed pellets in kilograms. Above the chart is the corresponding date for the currently displayed
information and below is the total consumption for this day:
Information about some of the current parameters
While on Pellet consumption screen, press the right navigation button again to access the next
information screen. It provides information about the set temperature and the total pellet consumption
since the last reset:
To reset the total pellet consumption press and hold the Menu button for more than 2 seconds.
To go back to Pellet consumption charts, press the left navigation button (◄).
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Indicator for next page
Date format
dd/mm/yyyy

Controller for pellet oven – NPBC-V3C-B
Information about the WiFi modem and the Internet connection
While on Information screen, press the down navigation button (▼) to access the second page.
Description of the fields:
ID – unique identification number for each modem
IP – Modem's IP address
WiFi mode – Modem's current state can be any of the following:
•Idle – No connection with WiFi router
•Access point – The modem is waiting for the local WiFi network's SSID and
password
•AP Associated – The modem is connected to a router
•Internet Access – Established internet connection
•Connected – The modem is connected to the information system's server
Snd/Rcv – Sent/Received data packages
If the control module NRC-6 is not equipped with a WiFi modem, there is only one message on the
screen:
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Controller for pellet oven – NPBC-V3C-B
Diagnostics
While on any of the Information screen pages, press the right navigation button (►) to access the
Diagnostics screen. To go back to the previous screen press the left navigation button (◄). This is a list
with short description, date and time of every registered event or error message. Press the down
navigation button to check the older messages on the next pages if there are more than 4 entries. A
yellow star marks the newest entry. Hold the Menu button for more than 2 seconds to reset the
information.
Table 2 is a list of all the messages that can appear on this screen and their full description. Messages
from 1 to 13 also appear on the bottom line of the main screen.
In most cases of error messages, there is a three-tone alarm signal. Some of the error messages
automatically disappear after the reason for the message is no longer present. Others can be
dismissed by holding the left navigation button (◄) for more than 2 seconds hile on main screen.
Table 2
Message Cleaning the
error
Description
1Back burning Button ◄The thermostat for back burning situation has been activated
5Ignition Fail Button ◄
10 ff PT Sensor automatically pt100 high temperature sensor is disconnected
11 Short PT Sensor automatically pt100 high temperature sensor is on short
14 Menu settings --- Date and time of the last access to the Factory Settings menu
15 No Exec module --- No connection with the Executive module
16 Power n --- Date and time when the power supply to the controller was
turned on
17 Power ff --- Date and time when the power supply to the controller was
turned off
1 Reset --- Date and time when the controller's software or the
information in the Diagnostics screen has been reset.
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Controller for pellet oven – NPBC-V3C-B
The error messages appear in red color on the bottom line of the main screen.
Automatic warning messages
In case of incorrect parameter input or if a change in the current menu caused changes in some of the
parameters from a different menu, the controller displays warning messages. For example:
Parameter settings.
NPBC-V3C-B has two main groups of parameters with an option for a different access level to them:
User settings and Factory settings. Press the Menu button once to enter the User settings. They are
available for any user at any time. Press and hold the Menu button for more than 2 seconds to enter the
Factory settings. If the option for an access code has been activated, only users who know it can access
the Factory settings.
The controller has different types of menus. The examples below explain these types and the way to set
the parameters in each of them. Regardless the menu type, if no buttons are pressed for certain time,
the controller goes back to the previous screen or to the main screen. After adjusting the parameters
according to your needs, press the Menu button () to save your settings.
•List choice – A red bar indicates the currently selected row. Press the up or down navigation
buttons (▲ or ▼) to move the bar and the right navigation button (►) to confirm the
selection. An arrow pointing down at the bottom of the screen or up on the top of the screen
indicates that there are more options in the corresponding direction outside of the visible area
of the screen. In this case, press the corresponding navigation button to go to the next or the
previous page. If there is an arrow pointing right on any of the rows on the screen, there is a
sub-menu with list choice again. While looking at any screen with parameter settings, press the
left navigation button to go back to the previous screen with list choice.
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Controller for pellet oven – NPBC-V3C-B
•Parameter setting screen – At the moment when such a screen is displayed, a pink frame marks
the first editable parameter. The left and right navigation buttons (◄ ►) move the frame to the
previous or next editable parameter. The up and down navigation buttons (▲ ▼) change the
currently selected parameter's value or put/remove a check sign. The parameter's type could be
any of the following: editable numerical value, list with text values or check box that
activates/deactivates a certain function. The numerical parameters are restricted in certain range
of values. When the end of the range is reached, the value stops changing, despite the
remaining sound signal for pressed button.
Press and hold the left or right navigation buttons ( ◄ ► ) to s itch bet een the parameters in the
current menu ith 5 positions per second.
Press and hold the up or do n navigation buttons (▲ ▼) to increase/decrease a parameter's value
ith 5 points per second or to bro se the list options in list choice menus ith 5 ro s per second.
User settings
While on main screen, press the Menu button once to access the User Settings. Press the up or down
navigation buttons to move the red line that indicates the selected row. Press the right navigation
button to access the menu corresponding to the selected row:
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More options available
on the next page
This option leads to
an additional sub-menu
with list choice
Selected row
Screen title More options available
on the previous page
Menu title
Pink frame that marks
the currently selected
parameter
Check box parameter
Status: Checked
Check box parameter
Status: Unchecked
Green text:
Additional information
or parameter's name
White text:
Editable numerical
or text parameter
Parameter type LED:
Light green: Active
Dark green: Inactive
Additional information

Controller for pellet oven – NPBC-V3C-B
Set Time & Date – The time format is 23:59 and the date format is dd/mm/yy. The day of the week is
automatically calculated after setting the date. After confirming the settings with the Menu button, the
seconds start from 0 only if the time has been changed. The automatic setting is available only if the
controller is equipped with a WiFi modem and connected through the Internet to the Naturela's
information system.
Language – Press the up or down navigation buttons (▲ ▼) to select the language for the controller's
menus and confirm your choice by pressing the right navigation button (►) or Menu
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More options
available on
the next page
This option is available only if
the controller is equipped with
WiFi modem and has
an access to the Internet

Controller for pellet oven – NPBC-V3C-B
Timers – Set and activate time intervals when the burner's work is allowed. If even one timer is
activated, the burner will work only during this interval. Moreover, the rest of the required conditions
must also be presented, such as: the work mode must be anything but “Standby”, the temperature of
the water in the boiler must be below the set temperature, OD and RT inputs must not be active and
there should not be any errors that require the burner to stay off.
The time in the column “On” must be before the time in the column “Off”! If necessary, set the “Off”
time first, to provide larger range for the “On” setting.
When using timers to control the burner, it is more convenient to get information about their current
state and their next action from one of the information fields on the main screen.
If there are active timers and the burner is turned on, the timers ill be excluded by pressing and
holding the button "On. / Off. " for more than 2 seconds.
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If there is a check sign,
the timer is active
Turn on the LEDs only for the
days of the week when this
particular timer should be active.
Light green LED: ON
Dark green LED: OFF
Days of the wee

Controller for pellet oven – NPBC-V3C-B
Select Fuel – Select the preset fuel profile settings corresponding to the currently used fuel. All
parameters for each profile must be set from Burning Setup menu in Factory Settings:
Display – Change the brightness of the display, if necessary
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Controller for pellet oven – NPBC-V3C-B
Manual Feeding – Manual control of the fuel auger motor and the circulation pumps. This function is
useful to fill up the auger motor when it's empty, to measure its capacity of pellet feeding for
calibration purposes, to test the pumps or to fill up the installations with fluid. The up and down
navigation buttons (▲ ▼) check/uncheck the box to turn on/off the output and left and right
navigation buttons (◄ ►) switch between the parameters.
The maximum time for manual control is 370 seconds (6 minutes and 10 seconds). After that the
controller turns off the outputs and switches to the previous screen.
Follow these steps to calibrate the fuel auger motor:
1. Detach the auger from the burner, but not from the fuel bunker.
2. Turn on the manual feeding to fill up the whole auger with pellets. If 370 seconds are not enough,
repeat this step several times. When the auger is full stop the manual feeding.
3. Place a bucket or another tank at the end of the auger motor to collect the pellets.
4. Start the manual feeding again and leave the auger working for any exact period (see a list with the
recommended periods for this setting in table 3)
5. Remove the bucket and measure the weight of the collected pellets in kilograms.
6. Calculate the auger motor's capacity with the following formula:
Ac = F*C,
where Ac is the auger motor's capacity
F is the weight of the collected fuel in kilograms
C is the constant from table 3 corresponding to the active time of the auger motor during the manual
feeding, measured by the timer in the menu Manual Feeding
Table 3
Active time of the auger motor, measured
by the timer in the menu Manual Feeding
Constant C
120 seconds (2 minutes) 30
150 seconds 24
1 0 seconds (3 minutes) 20
240 seconds (4 minutes) 15
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Timer for the auger motor's
active time