9 replies to this topic

[Leeroy Mechkins]

This guide is to help new players know what the Heat Efficiency stat in Mechlab means for their playstyle.

Heat Efficiency Usage Impact

<1.31 HE You cannot fire all your weapons regularly without shutting down.

1.31-1.36 HE You can fire all your weapons but need a long cooldown (30+ seconds) in between.

1.36-1.40 HE You can fire all your weapons but with about a 10-30 second cooldown in between.

1.41+ HE You can fire your weapons continually, with very short or no cooldown in between.

This is on regular maps. Hot maps appear to be around -.5HE and cold maps around +.5HE.
To summarize, 1.41+ HE will give you few heat problems, 1.36-1.40 some heat problems, and below 1.36 a lot of heat problems.

Edited by Leeroy Mechkins, 18 November 2012 - 12:23 AM.

[Turboferret]

The heat efficiency doesn't mean anything.
It's a measure of total per alpha vs. total heat capacity, not taking into consideration dissipation, which is the important thing.

[Leeroy Mechkins]

Yes, it is true, the HE is less as the number of weapons goes up. For example, 1.36 is fine on a Jenner, but much less ideal on an Atlas.
It's an imperfect rule of thumb, but for beginners its sometimes more useful to have a rough guide to start from than have no starting point.

If you want a very rough gauge, here it is:
For "good" heat efficiency (ability to fire all weapons regularly),
For light mechs go for >1.35 HE
For medium mechs go for >1.39 HE
For heavy mechs go for >1.41 HE

Of course, you don't need that heat efficiency if you are only planning to fire infrequently, cycle weapons or only use different weapons at different times.

Edited by Leeroy Mechkins, 18 November 2012 - 12:55 AM.

[SPencil]

I got 1.05 on my HBK-4SP with DHS, and I have zero problems with heat. (2 SRM6 & 2 LL)

While not a bad starting point for new players, I think it's lacking. Those values seem to only represent the optimal heat efficiency while constantly alpha-ing, or firing all your weapons within a very short time frame (CQB). What's the difference between firing both of my large lasers, versus chain-firing them? Heat is a tricky thing...

[Leeroy Mechkins]

SPencil, on 18 November 2012 - 12:53 AM, said:

I got 1.05 on my HBK-4SP with DHS, and I have zero problems with heat. (2 SRM6 & 2 LL)

While not a bad starting point for new players, I think it's lacking. Those values seem to only represent the optimal heat efficiency while constantly alpha-ing, or firing all your weapons within a very short time frame (CQB). What's the difference between firing both of my large lasers, versus chain-firing them? Heat is a tricky thing...

These figures do not apply for DHS.
And yes, these figures are for optimal heat with constant alpha, which is not the only valid playstyle.
You do not need that heat efficiency if cycling or alternating weapons.
Everyone find the numbers that work for you.
It will likely differ a bit from mech to mech and build to build.

Edited by Leeroy Mechkins, 18 November 2012 - 01:00 AM.

[MustrumRidcully]

Azrael1911, on 18 November 2012 - 12:33 AM, said:

The heat efficiency doesn't mean anything. It's a measure of total per alpha vs. total heat capacity, not taking into consideration dissipation, which is the important thing.

I believe it is actually a measure vs heat dissipation - but it doesn't matter, it's still not very illustrative of your mech's performance.

Some Alphas can be repeated every 0.5 seconds (Triple AC/2?), others every 4 seconds (Gauss + 4 Medium Lasers for example). That means quite a lot in how much heat you produce over time and how well you can dissipate it.


One "Heat Efficiency" stat that comes somewhere closer to the truth is calculating the heat you generate on average per second, and the heat you can dissipate on average per second. To figure this value out, either take the HPS values from Ohmwrecker's weapon charts, or take your weapons heat per shot, and divide it by their recycle time/cooldown. (For Lasers, add their beam duration to this time.)

But - while this makes a neat number that can tell you a bit - its meaning still varies a lot depending on your weapon loadout. A value of 0.5 can lead to very different times to shutdown - if you have only 2 Medium Lasers, it may give you an uptime of 40 seconds before you shutdown, if you have an efficiency of 0.5 with 8 Medium Lasers, you'd last less than 18 seconds.

To calculate the actual time you need before you shutdown, figure out the heat you generate per second, and the heat you dissipate per second. Subract the former from the letter to calculate your net heat gain per second. Then calculate your heat capacity (it's 30 + Heat Sinks for Single Heat Sinks, and somethnig more complicated for DHS). Divide the capacity by your heat gain per second, and now you know how long you last.

Or, if you want to be more "mathematical" about this:

Spoiler

Yes, there are ways to determining efficient amount of heat sinks. From the current experience in the game, I would suggest looking for a value that allows you to fire your "relevant" weapons without overheating in less than 20 seconds. You should usually experience this as "long enough" for most engagements. Heat Neutrality is a benchmark to determine aspects on weapon balance or general heat cost of a weapon, but when you want to know what your mech can do on a typical engagement, you will find heat neutrality to be a bit too conservative.

So, some math:
First, let's define some terms
:
H_G: Generated Heat (per second)
H_C: Heat Capacity
H_D: Heat Dissipated (per second)
T_S: TIme to shutdown
T_R: Time to recover to 0 heat after a shutdown

when H_D > H_G:

T_S = H_C / (H_G - H_D)

when H_D < H_G:
T_R = H_C / (H_D H_G)

To get into more detail (for heat system as of 2012/11/17).

n_s: Number of Heat Sinks
n_de: Number of Double Heat Sinks in Engine
n_do: Number of Double Heat Sinks outside of Engine

Heat Dissipation:
H_c = 30 + n_s
H_c = 30 + 2 * n_de + 1.4 * n_do

Heat Generation:
H_d = n_s * (0.1 / second)
H_d = (n_de * 0.2 + n_do * 0.14) / second

So, if we insert these values into the above formula for time to shutdown

Single Heat Sinks:
T_s = (30 + n_s) / (H_G - (n_s * (0.1))
Double Heat Sinks: T_s = (30 + 2 * n_de + 1.4 * n_do) / (H_G - (n_de * 0.2 + n_do * 0.14))


Now ,mind you -this is still an "idealized" value, since the damage in reality comes in discrete steps, not "per second wise", but in packages depending on your rate of fire of the different weapons. It is usually a bit higher than it actually is - and it can be about as higher as at least one full weapon cycle. For example, if you have a weapon that can fire every 3 seconds, and your calculation suggests with your setup you could last for 17 seconds, it's like you would overheat on the shot you take at 15 seconds.

To get the Heat Generation of each weapon, take its heat per shot and divide it by its recycle time. (For lasers, remember to add the laser beam duration to the regular weapon cooldown.) Or just take the values Ohmwrecker chart from the Guides forum.

To go back about what you may want your "T_S" to be:
I would aim for 20 seconds, but I usually prefer a bit "brawly" style of combat. That means that I usually have to sustain my damage for a bit. If you're a sniper and do not expect to get off more than 2 to 3 shots, before either you or the target get back to cover, you may do fine with a Ts of 9-12 (For most "snipery" weapon rate of fires, this should give you enough time for 3-4 shots, giving you a small error margin).
If you're a striker that moves in and out of brawls, you may have similar estimates.

Edited by MustrumRidcully, 18 November 2012 - 08:07 AM.

[Lege]

I like fast mechs around 1.1 heat efficiency, slow mechs around 1.3.
Not that they are hard and fast rules, just what I tend to aim for.
Fast mechs can break combat easily to cool off.
While your in the fight your only going to get off 2-3 alphas before you hide.
Slow mechs don't have that luxury, so they need to keep firing.
Some people are better at heat management than others.
If your dying a lot due to overheating, then load up on more heat sinks.

[p00k]

Leeroy Mechkins, on 18 November 2012 - 12:58 AM, said:

These figures do not apply for DHS.

yes they do

but they assume DHS all function at 1.4, even though the engine 10 function at 2.0 currently (and erroneously).

no really, test it. take a mech with DHS, slap, for example, a 300 rated engine in it. you should have 14 SHS equivalent heat dissipation (you actually have 20, but forget that for now)
now take an identical mech, but with SHS, put the 300 rated engine in it, and add 4 single heat sinks, to have 14 SHS heat dissipation. your heat efficiency rating will be the same
now, in game, the DHS one will perform better because the engine ones aren't working at 1.4 but rather 2.0

and yeah, it goes by dissipation not capacity

[MustrumRidcully]

Hola... I made something for tinkerers that want to optimize their mechs. It's a spreadsheet where you can enter your weapon loadout, declare whether they are supposed to fire or not for the calculation, and gives you how fast you'll overheat (if at all) ,and how much damage you can potentially generate in that time. It's adaptable in case weapon stats or heat sink mechanics change.

I'Ve set it to view only for now, which might mean it either doesn't work for you, or you first have to export it to yourself. Not sure yet, I am trying to figure this out.
https://docs.google....c1NDM0xuS05zM0E

EDIT: You can choose to download it as an excel sheet or an open document format.

Edited by MustrumRidcully, 18 November 2012 - 10:27 AM.

[DivineEvil]

For those who really care about truth, and not all that junk written above:

Heat Efficiency is a measure of heat dissipation, calculated by your Alpha total heat fatigue dissipated in 10 seconds. 1.0 HE means that it takes exactly 10 seconds to dissipate all the heat generated by your apha-stirke. DHS are calcualted as 1.4 dissipation power, and your dissipation can get broken when heatsinks are getting out of order due to critical damage, including those extra placed in your 275+ engine.