Why is this Industrial Steam Engine about to explode?

[Omicron]

Buildcraft engines dump *all* of their power when the moving bar hits the front of the engine. Their power is built up through the rest of the animation, then dumped in all at once. The internal buffer of most machines cannot handle that much power all at once, so most of it can't leave the engine.

So, if you have an engine producing 4MJ/tick, and if the engine pulses once per second (20 ticks), that is 80MJ delivered in one tick. If the engine pules twice per second, it works out to 40MJ delivered in one tick. If the machine you are powering can only use/store 20MJ at a time(tick), in the first cast, the machine takes 20MJ, leaving 60 still in the engine with nowhere to go. The next pulse, the machine takes 20MJ more, leaving 60MJ additional in the engine with now 120MJ stored. In the second case with 2 engine pulses per second, the machine would take 20MJ, leaving 20MJ in the engine. The next pulse, the machine would take another 20MJ, and leave another 20MJ in the engine for a total of 40MJ. Much better than the 120MJ in the first scenario, but will still eventually overload the engine.

Since buildcraft power can be "stored" in the pipe, the pipe absorbs the power from the engine, then trickles out the power to the machines over several ticks and averages it instead of the massive power spikes when powering a machine directly.

11 posts in, finally the correct answer. Quoting again because it apparently isn't common enough knowledge yet

This, by the way, is the same reason you shouldn't ever use anything but redstone engines on pumps, despite the multitude of videos and guides that use magmatic or even combustion engines there. The maximum burst intake of a pump is 10 MJ, and maximum continuous consumption is 0.5 MJ/t at 1 bucket per second.

 

[Whovian]

I think it's producing a LOT more power than is being consumed. I thought the railcraft engines didn't explode in this case, but rather shut down and required a whack with a wrench.

No, that's Thermal Expansion.

 

[KirinDave]

No, that's Thermal Expansion.

Well in any event, doesn't this mean duty cycle control needs to occur? If the engine is producing more energy that consumed over time, isn't that an explosion waiting to happen no matter how you spread it out over ticks?

 

[Omicron]

Actually KirinDave is partially correct. That feature is new in Railcraft 6.15, but none of the FTB packs have updated to it yet (IIRC).

 

[RavynousHunter]

What about running the pump off a single, low-output electric engine being fed by a hybrid solar panel? Feeding the pump via conduit, of course...always conduits. If I remember correctly, the hybrid solars have their own internal EU buffer, so you might not even need a batbox or MFE for the night hours. One engine, two conduits, one pump, one tesseract pair, and one chunkloader. Probably the simplest oil derrick one can make.

 

[Whovian]

Well in any event, doesn't this mean duty cycle control needs to occur? If the engine is producing more energy that consumed over time, isn't that an explosion waiting to happen no matter how you spread it out over ticks?

Yep. Well, without Energy Conduits. Using Conductive Pipes is still an explosion waiting to happen, though it's not the engine exploding.

Actually KirinDave is partially correct. That feature is new in Railcraft 6.15, but none of the FTB packs have updated to it yet (IIRC).

Hmm, interesting. Will keep that in mind.

 

[KirinDave]

Yep. Well, without Energy Conduits. Using Conductive Pipes is still an explosion waiting to happen, though it's not the engine exploding.

Yeah. I just find it very variable how soon people can reach the point where they can spare the resources for conduits. They're great and useful, but if you focus on an IC2, factorization, or pure TC (which someone on my server is now doing and it is both cool and scary) then redstone conduits for the occasional carpenter, thermionic fabricator or rolling machine is tough to justify.

 

[AlanEsh]

What kind of machines? Several of them drain a little bit of power continuously whether they're being used or not (rolling machines, thermionic fabricators).

Hm... I have pulverizer, powered furnace, rolling machine, liquid transposer, magma crucible... sounds like that's the problem. I guess I should put a switch on my last storage block and turn that off to stop the drain.

 

[RavynousHunter]

Hm... I have pulverizer, powered furnace, rolling machine, liquid transposer, magma crucible... sounds like that's the problem. I guess I should put a switch on my last storage block and turn that off to stop the drain.

Yeeeeeep, rolling machine's the source of your drain, then. TE machines only use power when they're running or filling their internal buffer. Maybe a cobble structure pipe w/ gate (if has work, then redstone signal on) that's got a bit of wire going over a redstone energy cell that's set to fill (both input and out) the working needs of the machine, but only doing so while its active would do the trick...

 

[Dafuq?]

Yeah the gate should work for the rolling machine, but afaik it doesn't work for the thermionic fabricator.

I personally have the two energy conduits that power my rolling machine and thermionic fabricator accessible. I switch them to supply mode only when I need the machines, preventing them from pulling energy all the time. I don't need them that often, and the omniwrench is on my hotbar anyways....

 

[netmc]

thermionic fabricators need a constant energy supply to keep the material liquid. if you use a cell, you can limit the power they consume. still needing to figure out if you can have multiple cells right next to each other, or if you need spaces in between. I want to place a row of thermionic fabricators to support the different liquid metals and tool/armor molds. I want to limit each fabricator to just enough mj/tick to keep the heat at the right level, but not at max, as that is a lot of wasted energy.

 

[AlanEsh]

thermionic fabricators need a constant energy supply to keep the material liquid. if you use a cell, you can limit the power they consume. still needing to figure out if you can have multiple cells right next to each other, or if you need spaces in between. I want to place a row of thermionic fabricators to support the different liquid metals and tool/armor molds. I want to limit each fabricator to just enough mj/tick to keep the heat at the right level, but not at max, as that is a lot of wasted energy.

Are you worried about one cell sending power to a neighboring cell rather than/along with sending it to the Thermonic Fabricator it is supposed to be supplying?

 

[netmc]

Correct. I am hoping cells will not directly power each other.

 

[Omicron]

I'm pretty sure I tested this once and they didn't.

 

[AlanEsh]

Should be easy to test with two full cells side by side and a pair of powered furnace or other TE machines that have internal power bars.
Since these "MFEs for MJ" don't have a specific output side, I would bet they'll output to each other. I'll test it tonight if you don't

/edit -- or in light of Omicron's post, maybe I won't