Tom, this Programmable Logic Controller is whats going to control my container Combined Heat and Power.
Since Im going to need something that is sturdy and not easily corrupted I chose to use a PLC.
This type of controllers is what all serious builders use when they build something that is automated and is supposed to run for thousands of hrs.
If you guys feel that the PLC stuff is boring I can focus on only the build it self?
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Roger,
It is just that most of us use or are planning to use very simple controls for the equipment we are operating. I know the industrial PLCās are great and reliable, and even available surplus. There is a learning curve associated with those that is just out of our usual area of experience. I have some surplus PLC stuff in my junkpile that I may use or just a few simple analog controls. You are breaking new ground with your fully automated system. Please keep sharing your progress!
Mike
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I have a question regarding automatic igniters, can a regular glow plug for a diesel engine be used for this?
Im not sure how long they can stay lighted before they break down.
The pellet oven igniters might work too but to fit it through a double mantled gasifier is not that easy.
My programing would be: set valve to atmosphere, start ignition for 60 seconds, start fan, after 60 seconds look at the temperature probe for the heart, if its going up dont repeat, if the temperature is going down then repeat the cycle.
After learning how long it would take to make good quality gas (lets say 5 min) stop fan, switch valve to motor, start solenoid for 5 seconds, if the RPM is going up or is stable over 1500 RPM dont repeat cycle, if the RPM fall down to 0 RPM repeat the cycle, if the motor dont start after 5 cycles shut down and display error message and send a allarm text msg.
This would just be to get the motor started.
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Roger, that sounds pretty complicated and expensive for an electronically challenged guy like me when the computer between my ears can do the same thing for free.
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Hey Don, if you are going to build a automated system you need something to govern it other than your self 
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Roger,
My home heating furnace uses a small plate-like surface that gets red-hot to ignite the fuel (propane) then there is a standard gas valve that will cut the gas off if the flame goes out using a bulb-type mechanical fluid sensor feedback to the valve. This is pretty standard stuff for home heating and small boiler controls. You need to get to know someone who installs this type of equipment, they can help you not re-invent the wheel!
Here in the USA, it would be a āPlumbing and Heatingā Company.
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Hi Mike, I have been looking in to a few solutions like that, but the problem start with the double mantled tank the gasifier is mounted in. I also need to make this service friendly so I dont have to tear down the whole gasifier just to replace the igniter. The glow plug of a large diesel engine or tractor is something Im looking at right now, with the threaded rod I can make it air/gas tight against the inner tank just above the heart of the gasifier with a pipe in pipe solution, the outer pipe so big that I can use a cup and a ratchet to dismount and mount the replacement.
I also like the glow plugs because they take up a small space and they are mechanically rigid.
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Roger, with auger feeding and running a generator connected to the grid, whatĀ“s the reason for shut down and start up? Maintenance of cource, but at such occations you are present and you donĀ“t need the light up automation. Also when a gasifer cools down things happens. Toasted fuel will glue to the lower funnel and form a bridge, which will have to be busted lose and the charbed tightens and needs some attention. If it was me I think I would try to run as long as possible between shut downs and do manual lightups. But thatĀ“s just me 
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Hello Roger .
On one of my earliest gasifier I tried the diesel glow plug for starting . I had to install it far enough away from the char bed for it to survive the heat.
This area of the gasifier contained toasted wood or simi char. The glow plug would light the simi chared wood but would take a while for the fire to travel down to the char bed area.
I ended up taking the glow plug out and lighting the gasifier through the fuel hopper right down on the char bed . With me it was much faster lighting up with the torch and clean gas right from the lighting .
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I agree with Joās philosophy. And Wayne speaks from experience, thatās an extreme environment.
I might aim for some kind of torch lighting, that would be sure ignition, and can be made automatic if it needs to be.
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JO one of the reasons is that I dont know how long durationās I can run the gasifier, I want to be able to remote start it again from my phone, in the summer I dont need so much heat and I expect that I cant run for so long before I reach high temp.
But like you say its no problem lighting it manually, the wife would like a button to press if Im not home thoā¦
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Hi Wayne, I dont mind that it would take some more time to do the light up, this is a stationary system and its no rush to drive of like you guys do
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Roger, that explains a lot. I didnĀ“t realise you were planing on capturing waste heat, but looking back on your initial post I can see you added some information and pics.
We all have different needs and priorities. I guess most of us here are doing all this mostly because of the fun of it. Some get the thrill from pushing limits. Personally I get part of the thrill from saving a few pennies (ƶren), which to me, for some reason, is much more fun than earning money. And of corse the wonderful smell of wood and smoke is hard to beat.
I heat with wood using a 4m3 storage tank, but by the end of April when the heating season is over I donĀ“t light a single sticker in the boiler until September. I feel the small amount of hot water needed doesnĀ“t justify running the boiler. I have a 10m2 solar panel (with coolant) that takes care of 75% of the need during this period and the rest is topped off with electric.
Also, when fall comes itĀ“s so much more fun again to light up the boiler. (Mother used to hide our toys in batches for a couple months at the time. After sitting for a while the old toys felt brand new again.) For some reason I donĀ“t seem to need to rest from the gasifier though.
By now IĀ“ve forgotten what I was aiming at. IĀ“ve been in bed in the flue during the week and maybe itĀ“s still the fewer talking. I donĀ“t expect you to answer any of this. I guess I just wanted to share my personal view of effort and return in this.
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Iām sorry I zoned out a bit when offering gas valve advice, I assumed you were just trying to ignite finished wood gas to do some work, like heating water or a flare. You could use your waste heat in the summer to heat a nice swimming pool, or something I have been toying with for years, fill a large underground storage tank with hot water and use it later. Maybe run a Sterling heat engine (Rabbit hole alert!!) 
That glow plug looks like it would be tough enough, but like Wayne said, direct contact with the char bed when in operation is a crazy hot environment. You could use some kind of propane burner to light the char bed, or like J.O. said, just leave it run as long as possible. You should think of your gas plant as an industrial process you could throttle back, but keep the fire lit, like a steel mill, or nuke plant.
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JO, I am drawing up the plant in Fusion 360 so I can see how much space I have in the container and Ill post pictures of it when I have most of the components drawn in.
In the future I hope to have some solar too like you, to add both heat and electricity, that is further down the road tho.
Like it is for you this is going to be a hobby for me to both save me some money, but also to keep my creative skills honed, it gives me ideas that I can use at my workplace.
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Mike, my plan is for when I have a controlled shutdown to stop the feed in to my preheated auger screw and just let it empty it self in to the gasifier, based on experience I would then know how long I need to run the gasifier for it to be almost empty, this way I wont have problems when I start it up again, hopefully I would stil have a char bed in the bottom and fresh wood chips on top of that.
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I open a 1/2 inch plug and ram a long metal rod through the gasifier to break up bridging and voids before restarting .
I like advice to keep running . I have a gas dryer igniter for flare
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Having a working gasifier with a flare .Then you try to start the engine . The strangest run was a snow crash of the display for the DSE 8610 because it was receiving more errors then it could display , still generating power engine ramping up and slowing down . Trying to start engine with emergency stop depressed . Trying to start with governor sealed with tar or inoperable . Trying to start with no spark , fouled plugs , loose connection to coil . Replaced governor with something cheap
. got engine running could not get engine to power generator no power from engine then no flare . Had to back flush gasifier with water pressure , gas outlet from gasifier was sealed blocked with char tar . At this time I tried to remove dse 8610 as not needed or wanted . I then could not get power to oxygen sensor ,Lambda for air fuel ratio . at this point I just stopped work on gasifier powered stationary generator
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Henry,
You have so many problems here it is hard to sort through them. I will try to help. I briefly looked at the web page for the DSE8610 Automatic Generator Control System. I think you can work on some basic manual operation before you worry about that too much. Lets start with the flare and the amount of tar you are describing. You say your engine speed governor is sealed with tar or inoperable, plus your gas outlet was blocked with tar. This is a good place to start. Is your wood feed stock dry enough and is the average size of a chunk or chip too small or too large for your gasifier design? Also, is the gasifier the right size for the engine / load you are running? Too small or too large will cause excess tar. Others with more experience can help out, but you need to figure out these basics and should be able to flare for an hour or more without complications.
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