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Current Harware Version: 0.0.1
Current Firmware version: 0.0.3 

Version 0.0.3 ARM-GCC compiler http://www.vscp.org/download/thehulk2_firmware003.zip

The HULK was a project built many years ago to control a wood burning furnace. The project came about because the control card for the system was broken when I bought the used system. Originally this was a tank for wood-chips (not sure this is the right English word) which I used for wood pellets. A motor driver screw that fill up a burning chamber in front of the furnace with fuel.

The original HULK did not have any light mechanism and the fire must be kept lit all the time so the functionality of this system was to keep a full fire in the burning chamber when the preset furnace temperature has not been reached and a slow burning fire when the preset temperature was reached. Quite an easy task.

The system is used to warm up our house (wish is both the home of my family and the office for my wifes and my business on the ground floor).

This original system had some problems from a security perspective. The main problem was that the fuel transport mechanism and the burning chamber was on the same level and therefore there was a risk for a fire in the transport mechanism itself which in worst case could reach the fuel storage tank. To prevent this a security mechanism was mounted on the screw that filled it with water when it reached above a certain temperature.

I bought the mechanics for the HULK II from a good friend of mine. This was a combination of things he built him selves and a commercial system. The system also had a lightning mechanism wish is a good plus. The first two years I had this system I used the embedded control card that came with the system. This worked good most of the time but there was some pickups in the system that made it fill fuel in an uncontrolled way and sometimes start and stop the fuel fill motor also in an uncontrolled way.

As seen in the drawing above the fuel transport mechanism does not live on the same level as the burning mechanism also the fuel storage is smaller. I now have to fill fuel very day but I will solve this later by adding a second screw from my 30 m3 main fuel storage.

The schematics picture above show the burning chamber. The transport mechanism screw that fill fuel. The fan that provide primary and secondary air for the fire. The heater that light the fire when needed. The fire detector that detect a fire. This is just a LDR that have have a main sensitivity in the IR region of the spectra. Its the same thing that is found in most oil burners.

The control scenarios are very simple really

To light the fire and start up the system.

1. Power Fan and heater
2. Fill fuel.
3. Wait until fire is detected and turn of heater if so starting full screw.

While the furnace temperature set point is not reached the fuel screw and the fan is running. When the set point is reached the fan is run for some time to burn out fuel in the burning chamber and lastly the screw is run for a short time to prevent any backfire in the screw. The system is then put to rest until its time to start up again.

Some years ago a lightning strike took out the water heater in my house. The control mechanism was fried and looked more like a piece of toast then a circuit board. I then built a Microchip PIC16F84 based board to control this unit.

The unit got four 3kW electrical elements. There should be a delay between switch on of elements and in the original design there where two stages. First 6kW was switched on and after two hours another 6kW was switched on.

The temperature in the heater is sensed with a Smartec temp sensor (see http://www.vscp.org/vscp/modules/kelvin_smart2/index.html ) and there is a mechanical over temperature protection to prevent the system from boiling in case of control system failure. This has been needed a couple of times when the sensor has been burned buy other nearby lightning strikes.

The heater is used both as a backup during the winter in case the main system fails and during the summer for hot water production.

The system got a RS-232 control interface that allows me to control certain functionality of the system.

1. Preset water temperature can be set.
2. Can be enabled/disabled.
3. Current hot water temp can be read.
4. and more…

With this functionality the hot water temperature could be lowered during periods and raised just before the need for a lot of hot water occurred.

I decided to add control for this system also into the HULK II. This was because of two reasons. The original control software was written in assembler and the PIC16F84 was now obsolete.

For those interested in this original control software (!!!) it is available in the VSCP CVS under /can/src/eda/hardware/mumin/picnode/esc1

So the new system should control the new HULK II hardware and the water heater. Another important consideration was that I wanted to use VSCP to control the system externally as this is what I use for the rest of the functionality of my house. I use CAN and Ethernet for this but decided to use can for this system.

When I was thinking of the design Circuit Cellar ran a design contest for the LPC21xx series of ARM based controllers from Phillips. I entered this contest and got a Keil MCB2130 board. This board have a LPC2138 on board and thus plenty of I/O, Flash, A/D's etc for my project. I have never before worked with the ARM core and also saw this as a great way to get to now that arcitechture.

The main design goals was something like the following:

• I wanted lots of LED's that showed status for different parts of the system to help to search for errors when there is some problem.
• I wanted an LCD with buttons that showed status and also let me configure setpoints etc.
• It should control two 380V 3-phase trasport motors.
• It should control one 240V Fan.
• It should control one 240V Heater.
• It should have an A/D input for a fire detector and a fire detector reference.
• It should be able to directly control a 12V alarm.
• It should be able to report furnace water temperature, return water temperature, temperature on the transport mechanism closest to the burning chamber.
• It should report hot water temperature.
• It should be able to control the four 3kW heating elements of the water heater in two stages.

The Keil MNC2130 board is documented here http://www.keil.com/mcb2130/ It is a great board but was missing CAN so I used the Lawicel CAN232 for the CAN link. http://www.can232.com/ The second serial port is used for the CAN232 adapter and the first is used for status and debug information.

Above is the driver for the LED's and relays to control the two 380V three phase motor (Motor A, Motor B), the relay for the 240V FAN, the relay for the 240V Heater and the relays for the two water heater stages.

This is the alarm driver. Note that R5 may not be needed for some alarms as they has enough internal resistance.

This drawing show the control connections for the furnace control

and this show the control connections for the water heater.

The above schema is the control electronics for the water heater.

The above is the fire detector input stage. Some input protection is also added but not shown.

Dallas 1-wire interface is used to read less important temperatures.

Also needed an eeprom for persitant storage both for VSCP data and for device parameters.

Added to this is a switched power suppluy for +5V DC and +12V DC, button and LED interfacing. Mounted in the box it all looks like this

This picture show the clectronics mounted on the chassis

Another chassis picture

The driver stage

The alarm driver

EEPROM and 1-Wire electronics

and mounted in the box

The front

This is another picture of the front on an active system. The LCD display show the water temp of the furnace (no temp sensor connected here). The system is active and therefor the fan an transport A+B is running feeding fuel to the burning chamber.

The Forward, Down, Up, Enter buttons can be used to move around in the menu system and look at different live data, enable disable the system or certain functionality and configurate setpoints and other parameters. The force transport allow me to manually fill fule in the burn chamber. A feture that is very useful when the transport mechanism has been run empty and the preset fule fill time before start is to short.

This is the realybox

Fire in the burning chamber

The HULK II

The HULK II

The HULK II

The HULK II

The old water heater control unit

The water heater elements with the accumulator tank.

Send event every minute.
CLASS.MEASUREMENT TYPE=6, Temperature
Format: Integer Format (one byte).
Data coding: 0x60 Index = 0

Send event every minute.
CLASS.MEASUREMENT TYPE=6, Temperature
Format: Integer Format (one byte).
Data coding: 0x61 Index = 1

Send event every minute.
CLASS.MEASUREMENT TYPE=6, Temperature
Format: Integer Format (one byte).
Data coding: 0x60 Index = 2

Send event every minute.
CLASS.MEASUREMENT TYPE=6, Temperature
Format: Integer Format (one byte).
Data coding: 0x60 Index = 3

Send event every minute.
CLASS.MEASUREMENT TYPE=6, Temperature
Format: Integer Format (one byte).
Data coding: 0x60 Index = 4

Send event every minute.
CLASS.MEASUREMENT TYPE=50, Relative Level
Format: Integer Format (two byte).
Data coding: 0x60 Index = 0

On/off

CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=0

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=1

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=2

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=3

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=4

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=5

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=6

CLASS.ALARM TYPE=2, Alarm occurred.
Zone=Configurated
SubZone=7

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=8

On/off.
CLASS.INFORMATION TYPE=3/4, ON/OFF
Zone=Configurated
SubZone=9

The following events can be sent to the module to control certain functionality.

Send
CLASS.CONTROL TYPE=5/6, TurnOn/TurnOff
Zone=Configurated
SubZone=7

Send
CLASS.CONTROL TYPE=5/6, TurnOn/TurnOff
Zone=Configurated
SubZone=8

Send
CLASS.CONTROL TYPE=5/6, TurnOn/TurnOff
Zone=Configurated
SubZone=9

• 2006-06-28 - 1-Wire removed. P0.17 is now Furnace core temp and a SmartTemp sensor is used.