Engine modification: Changing from 2 fuels to 1

[TheAlmightyOS]

I am having some difficulty modifying a part. Namely an ION engine

Here is the stock module:

MODULE{
	name = ModuleEngines
	thrustVectorTransformName = thrustTransform
	exhaustDamage = False
	ignitionThreshold = 0.1
	minThrust = 0
	maxThrust = 2
	heatProduction = 0
	PROPELLANT
	{
		name = ElectricCharge
		ratio = 1.8
	}
	PROPELLANT
	{
		name = XenonGas
		ratio = 0.1
	}
	atmosphereCurve
 	{
		key = 0 4200
 	}

}

Now, I wanted to change this engine so that it only runs on electricity. So I removed the XenonGas portion from the module. I then changed the max thrust from 2 to 40. Although I know the fuel intake scales with the thrust, I also wanted the it to require an even higher electric charge to operate as it no longer required xenon so I changed the ElectricCharge ratio from 1.8 to 3. This is what it looks like now:

MODULE{
	name = ModuleEngines
	thrustVectorTransformName = thrustTransform
	exhaustDamage = False
	ignitionThreshold = 0.1
	minThrust = 0
	maxThrust = [COLOR=#ff0000]40[/COLOR]
	heatProduction = 0
	PROPELLANT
	{
		name = ElectricCharge
		ratio = [COLOR=#ff0000]3[/COLOR]
	}

	atmosphereCurve
 	{
		key = 0 4200
 	}

}

What I got was an engine with a fuel consumption of infinity. I messed with the atmosphereCurve thinking that was the issue but no.

I am looking though the documentation on here but I have not found my mistake yet. I am sure it is something easy that I fouled up or missed. I suspect that "ratio" is the problem yet I don't understand how I can set the fuel consumption rate without it?

[MrHappyFace]

The fuel needs to have mass, ElectricCharge has no mass.

[TheAlmightyOS]

Well that was quick. Thank you

So in order for ModuleEngines to function, it requires fuel which has mass. being as I doubt squad wrote a module for a purely electric means of propulsion though space as it defies physics as we know it, I am probably going to have to write one.

Could you do me one last kindness? I have unity installed and at the project wizard, however I am not sure what packages to import in order to create a module. First time using it

[NathanKell]

You don't use Unity for coding; you write the plugin in C# and compile it. Here's the (old but AFAIK still valid) guide:

http://wiki.kerbalspaceprogram.com/wiki/Plugins

You might want to, instead, do what FireSpitter does: have the ModuleEngines use a resource that the part itself (via a ModuleGenerator) creates. Check out FireSpitter's electric engines; they do this (using FSCoolant IIRC).

[TheAlmightyOS]

I will take a look at what FS did for his. I think I get the idea as I messed a little with the ModuleGenerator for a mater-antimater reactor mock up. But I think I will take the harder path and try coding something. That way I learn something about the game engine instead of just messing in config files.

Thanks for the link

I'll see ya around