I need to remote start a diesel genset from a remote location but i can't work out how to approch it. What i need is something that can start the engine when i press a button or flick a switch and when button is pressed again (or switch flicked back) can stop it.
The first problem is that start and stop are not the same, when i need to start the engine i need to have Ignition ON, Glow plugs on for 10sec, Crank engine for 4sec, wait about 20sec and then switch power on.
When i need to stop it i have to remove the power, Stop engine (this is a 1sec signal for the solenoid) and remove the Ignition.
I originally built a cascade of 555 to time the starting sequence but that doesnt help the stop sequence. Now i am thinking to use logic to control the all lot and keep the 555 only for the timed sequences (glow, crank and stop). I know i could use a pic but i am not skilled to use it. I have basic electronic skills but can work with logic if the problem is not too complex.
Any suggestion?

 

Here your idea is more clear.

Does the glow plugs and crank need to activated the same time with the ignition and terminate after the delay you said?
Or they need to be switched in sequence and last as long as the delay you said?

 

Ok, assuming that everything is off, button is pressed (so will start engine) sequence will be as follow:

1) Ignition comes ON and stays on (like in cars when oil and battery lights come on)
2) Glow plugs ON for about 10sec
3) Crank for about 4sec
4) pause for about 20sec (this is to allow engine to stabilize)
5) Power ON
end

when button is pressed again, engine is running so will stop it in this sequence:

1) Power OFF
2) Stop (this is a 1sec max used to open the solenoid)
3) Ignition OFF
end

 

Yes but the crank needs to be turned on after the glow plugs turn off?

 

yes correct, at the end of (start sequence) only Ignition and power will be ON

 

I am sorry I am asking too much but I don't want to design something and then redesign it because of wrong functionality. Please write down the sequence you want like that:

1. Ignition relay on
2.Ignition relay stays on and glow plug relay on - glow plug relay off after 10 sec
3. .......

and so on. This was an example, make the same for both starting and shutting off sequence. If I understand exactly what you need I will try to design it tonight or in a few days because I have exams at university this week.

 

"Ok, assuming that everything is off, button is pressed (so will start engine) sequence will be as follow:

1) Ignition comes ON and stays on (like in cars when oil and battery lights come on)
2) Glow plugs ON for about 10sec
3) Crank for about 4sec
4) pause for about 20sec (this is to allow engine to stabilize)
5) Power ON
end

Shouldn't there be another step between #4 and #5 to somehow receive feedback from the generator that it actually started before cutting in the electrical load? Say if fuel was empty and generator couldn't start, I'm sure turning on the electrical load without the generator actually running would have unpleasant consequences?

Lefty

 

Leftyretro has some good points. Think again what do you want to do and then come here with a nice description (and a diagram if possible, it helps a lot).

 

For feedback you could use the oil pressure gauge sending unit. You will not have oil pressure if the motor isn't running.

 

Very good point LeftyRetro. As engine has the standard lights for Oil and Battery we can check them both? Also if i bring these two lines i could use them to trigger a stop sequence in case of malfunction? I am adding a little block diagram with graphs as well and hope it is clear enough. I tried to show as much as i could think of. Connection to engine is made via automotive relays in parallel to key switch and i am planning to have relays onto this board to drive the relays at the genset. Power relay (in this board) will drive the contactor at the switch board. I am also adding a picture of the gensets.
Please let me know if something is not clear enough.

 

Morning Franco oz,

By meaning "remote location" do you want to go wireless or is there actually wires running to where your on/off buttons would be possitioned?

 

i have already one rs485 line arriving there and some parts of the switchboard are controlled via RF remote control.

 

Franco,

I have seen your diagram, it doesn't look very complicated. I will try to make the circuit as soon as possible because I have exams now, I someone else don't do it before me.
Are you interested in using a PLC to do the whole job? I suggest you the PLC solution because the cost will be the same (maybe cheaper) and also you can change the function of the whole system by just reprogramming it. Have a look at Crouzet's PLCs here:

www.crouzet.com

I have used a Crouzet PLC and I can make the code to program it if you are interested.

 

Mik, thanks for all the time you are investing to help me. I am looking at the Crouzet PLC and will try to get some pricing for a starter kit. I made few mistakes "rushing" into this project and now i have a clear picture of what i need. I will try to put something down and see how i go. Good luck with exams, my circuit can wait... and gives me an opportunity to give it another go. Thanks again.

 

To start with PLC you need a programming cable and the software. I think you can download the software online from their website. I suggested you Crouzet PLCs because they are easy to program. The code is not written but you just connect building blocks (each block offers a function) on the PC and the software translates these blocks into code during programming.

Thanks about the exams. I have the last one tomorrow

 

there are some called smart relays too, i think u are talking about ladder programming? I looked at it few months ago but here in Australia they are quite expensive. Not sure have to check it out again.

 

It is not ladder programming, it is like you build a circuit in a circuit simulator. You can order the PLC from the internet and they will send it to you if you can't find any in Australia. Look in the attachment to see a snapshot of the software I use for Crouzet PLCs. If you build a control board from discrete components like gates, transistors, etc the cost will be more than buying a PLC.

 

I looked at different options, i can use RS485 and write my code in VB or buy USB to I/O, i could use parallel port too but i opted to have some "local" control inside the gensets. That is main reason i chose to do it myself. I will look more at crouzet range of plc. Any place you can suggest to buy them? Making this board using standard logics will be too much? I may try and give it a go, worse case you will tell me it won't work!

 

Yes, making a board will cost about the price of a PLC or maybe more. Also, you can't change the function unless you change some components where as with a PLC you can change the function by just reprogramming it. I am not saying that to make you buy a PLC, it is just an advice.
If you will use the port of a PC to do it then you things will be easier if the computer is near the machine. If the computer is far then you will need to translate the low voltage used for logic levels out of the PC port to a higher voltage as to be able to be transmitted at a long distance without losing information (noise etc).
Have a go to design a circuit and then post it here to check it and make improvements if needed.

 

Hi folks,
Im working on my tired old Ford diesel truck and stumbled on this thread...I joined immediately.
Sounds like a great little gadget to add for those cold or rainy mornings.
The idea of a PLC being added to my truck sounds interesting and fun to play with also.
It sounds as if you plan on this thing riding piggyback on existing diesel electrical system rather than replacing anything. All the more reason, Im interested in the results. Be fun to find out how many conditions something like a PLC could monitor and tackle.
Good luck, Im glued to this thread.
Cornbread