How much convert-o-tron power do I need per drill-o-matic?

[Newnard]

This is an ISRU factory I'm planning on sending to Minmus. It has:

• 1x Drill-o-matic (the 1.25 ton version, not the Jr.)
• 1x Convert-o-Tron 125 (the smaller one, because it balances nicely weight-wise with the drill)
• 8x radial ore tanks (at 75 ore per tank, total capacity 600 ore)
• 2x Thermal Control System (medium)
• 4x Radiator Panel (large)
• about 4.5k electric charge capacity
• 8x gigantor solar panels.

I'm using some mods, but most of them hopefully aren't relevant to this question -- exception might be TAC life support because the kerbals need electric charge to stay alive. The complete list is:

Chatterer - 0.9.7.86
Contract Configurator - 1.9.6
Contract Pack: The K Files - 1.1.1
Contract Pack: RemoteTech - 2.0.1
Contract Pack: Tourism Plus - 1.4
Kerbal Attachment System - 0.5.5
Kerbal Engineer Redux - 1.0.19.4
Kerbal Inventory System - 1.2.5
KSP-AVC Plugin - 1.1.5
Final Frontier - 0.9.8.1882
RCS Build Aid - 0.7.7
RemoteTech - 1.6.9
SmartParts - 1.6.6
TAC Life Support - 0.11.2.1
Kerbal Alarm Clock - 3.5
TweakScale - 2.2.6
Waypoint Manager - 2.4.5

So here are the actual questions: If I'm planning on running the drill and the convert-o-tron pretty much continuously until the LFO tanks are full...

1. Which processes ore faster, the drill producing the ore, or the convert-o-tron 125 turning it into fuel? In other words will my ore tanks fill up because the drill is faster, or empty out because the convert-o-tron is faster?
2. If my ore tanks fill up, will the drill shut down? If so will it start back up when some space becomes available?
3. If my ore tanks empty, will the convert-o-tron stop working, or simply wait for more ore to be put in the tanks?

I know the answer to question 1 potentially depends on the abundance of ore at the dig site, but I'm looking for a general answer based on people's typical experiences. This is my first attempt at using the stock ISRU system, I don't want to waste funds and time sending a mission that has no chance of working, and for mental health reasons I don't want to start up a separate sandbox to test this out for free first.

Thanks in advance for any replies. Hints regarding electric charge and heat dissipation would also be very welcome.

Edited March 15, 2016 by Newnard
Whoops bad title, etc.

[FancyMouse]

2.3. As long as they still stay on, they'll operate at a reduced rate where everything (tank, drill rate, ISRU rate, temperature) is in an equilibrium.

1. Note that ISRU can convert LFO at 3x rate by activating all of LFO+LF+O, so really, in most cases one is enough, and spam as many drills as you can.

Edited March 15, 2016 by FancyMouse

[Superfluous J]

It actually depends on several things, most notably the concentration of ore and the skill level of the highest skilled engineer in the ship, if present.

Drills will drill 0.075*c*m per second, where C is the concentration and M is a multiplier based on engeneer skill level:

Level	Multiplier
☆☆☆☆☆	5x
★☆☆☆☆	9x
★★☆☆☆	13x
★★★☆☆	17x
★★★★☆	21x
★★★★★	25x

(Stolen from the wiki)

So if the concentration is - say - 10% (a good percentage) then your unmanned station would drill 0.075*0.1*1 = 0.0075 ore per second. A level-5 engineer would bump that oup to 0.075*0.1*25 = .18 ore per second, or an ore unit every 6 seconds, or about 10 ore units a minute, or about 600 per hour. The converter is easier, it just converts ore to LOX at the rate of 1 combined unit per second, costing 0.5 ore per second.

More important than which goes faster is what can they do in 6 hours. When you leave your mining base and come back six months (game time) later, a simulation is run very quickly that drills and then converts things in 6-hour blocks. Because the bottleneck is likely to be the converter, you can just make sure the ore tanks have enough room to hold 6 hours of ore supply for the converter, or 360 minutes, or 21600 seconds, or 10800 units. Unless I mathed bad. But the idea's sound.

Edited March 15, 2016 by 5thHorseman

[Newnard]

4 minutes ago, FancyMouse said:

2.3. As long as they still stay on, they'll operate at a reduced rate where everything (tank, drill rate, ISRU rate, temperature) is in an equilibrium.

1. Note that ISRU can convert LFO at 3x rate by activating all of LFO+LF+O, so really, in most cases one is enough, and spam as many drills as you can.

Thanks FancyMouse!

3 minutes ago, 5thHorseman said:

More important than which goes faster is what can they do in 6 hours. When you leave your mining base and come back six months (game time) later, a simulation is run very quickly that drills and then converts things in 6-hour blocks. So, you should make sure you have the ore tanks to hold 6-hours worth of ore, and then let everything else sort itself out. Also, because the bottleneck is likely to be the converter, you can just make sure the ore tanks have enough room to hold 6 hours of ore, or 360 minutes, or 21600 seconds, or 10800 units. Unless I mathed bad. But the idea's sound.

And thanks 5thHorseman! This bit about the fast-forward algorithm was completely unexpected.

I note that FancyMouse and 5thHorseman seem to disagree on whether the drill or the ISRU converter is a more likely bottleneck, but that is really a side effect of 5thHorseman factoring in engineer skill I think.

 

[Superfluous J]

I also never thought to run the converter in double time by activating LF/O, LF, and O. So we're all learning things here

[FancyMouse]

7 minutes ago, Newnard said:

I note that FancyMouse and 5thHorseman seem to disagree on whether the drill or the ISRU converter is a more likely bottleneck, but that is really a side effect of 5thHorseman factoring in engineer skill I think.

Oh well I should've said I play in moderate (80% global multiplier) career (low star eng). Along with the 3x rate, ISRU has never been a bottleneck to me. But things might change in a normal sandbox. You did mention that you just need the playing experience so I stated my experience in my earlier reply

[Nich]

The small converter sucks I think it is 4 times less efficient then the big converter.  If this is a factory just put the big converter on it.

[mrclucks]

I built an ISRU factory the other the day with 6 large drillers and 6 smaller convertors manned by two level 3 engineers and tested it on the launch pad.  I find that they convert ore fairly quickly.  They also seem not to overheat regardless if I have my radiators or solar panels deployed, however that will probably not be the case in a vacuum

Edited March 17, 2016 by mrclucks