Passive shield tanking

From EVE University Wiki
Revision as of 14:54, 9 April 2017 by Abelard Andedare (talk | contribs) (Thermic/Thermal)
Jump to: navigation, search
This article should be cleaned up or improved.
The reason is: Overlaps with Shields: How They Work.
{{{1}}}
This page covers the use of shields as a passive tanking strategy. As such, it focuses on the advantages of passive tanking and the process of fitting a ship to use a passive tank. It assumes that the reader knows the fundamental principles of how shields work.}}

The Basics

This section gives a quick overview of passive shield tanking techniques. A more detailed discussion follows.

There are three fundamental approaches to shield tanking:

  • Active – uses modules that draw on the ship's capacitor to improve shield performance,
  • Passive – prefers modules that do not draw on the ship's capacitor; mostly to improve shield recharge rate,
  • Buffer – prefers modules that do not draw on the ship's capacitor; mostly to increase the shield's capacity and resistance.

These are discussed and compared in the E-UNI course on Shield Tanking. Passive Tanking is discussed in detail in this article.

When to Use Shields

The general article on Shields covers the advantages and disadvantages of shields as a means of defense.

Shields and armor should NEVER be mixed when fitting a ship tank for combat.

In general, you should consider a shield tank whenever one or more of these conditions holds true:

  • your ship has a bonus that favors shields,
  • your ship has a shortage of low slots or a surplus of mid slots,
  • you need to favor modules that improve weaponry (which tend to fill low slots),
  • you have less need for modules that support tackling and scanning (which tend to fill mid slots),
  • your skills are biased towards shields.


Example: The Caldari Moa
  • Bonus: 4% to all shield resistances
  • Five mid and four low power slots
  • Bonus to medium hybrid turrets: 5%
  • Five turret hardpoints
  • Fifteen m3 drone capacity
caldari moa attributes

With low drone capacity, bonus to turrets and five guns, this looks to be a close combat ship. The bonus to shield resistances is a difficult benefit to ignore, and it has enough mid power slots to accomodate a shield tank.

The Passive Tank

The Passive approach to shield tanking:

  • depends on the natural recharge rate of the shield
  • uses modules and rigs that boost the recharge rate
  • uses modules and rigs that increase the capacity of the shield, which in turn also boosts the recharge rate
  • prefers modules that do not draw power from the capacitor.

The pilot should keep in mind that a shield tank is a defense. The ship has a purpose, and resources in support of that purpose must also be fitted. Too much defense can be as much of a mistake as too little.

Strategy

To construct a shielding system that will grow back at least as fast as it takes damage. This approach will work best in situations where damage is more or less constant, or growing slowly, preferably over a longer period of time. It will also work in situations where the pilot can remove the ship from combat periodically to let the shields recharge.

Tactics

These methods either limit damage to a manageable amount, or they provide time for the shield to rebuild itself.

  • Kiting: by running from the enemy, and stringing them out "like the tail on a kite", and then slowing to match their speed, the pilot brings the enemy ships in one at a time, thus keeping shield damage constant.
  • Long range combat: by using speed to stay beyond the range of enemy ships, and applying long range weaponry, the pilot keeps shield damage low.
  • Acton breaks: through "hit and run" attacks, or by means of natural breaks in the fighting, the pilot allows the shields time to rebuild.

The Details

A passive shield tank fit wants to meet the goals listed above. On the other hand various other concerns, including such as stacking penalties, pilot skill levels, and power slot availability will impact on the final choice of modules and rigs.

Shield Recharge Rate

As you know, the Shield Regeneration Rate increases by more than double, based on Shield Capacity, as the shield takes damage. Since this change is a percentage, a ship that starts with a higher average regeneration rate will get a bigger boost in its optimum rate. In addition, since the shield regeneration time is constant, a larger shield will regenerate faster.

For example, these are all Caldari ships. Many Caldari ships prefer shield tanks.

Ship Type Shield Capacity (hp) Shield Regeneration Time (sec) Average Regeneration Rate (C/T)
CaldariKestrel (frigate) 500 650 1.3
CaldariCorax (destroyer) 950 625 1.5
CaldariMoa (cruiser) 2500 1250 2.0
CaldariDrake (battlecruiser) 5250 1400 3.75
CaldariRaven (battleship) 7000 2500 2.8

Without any modules, and assuming the pilots had the same skills, the Drake would rebuild its shield almost three times faster than the Kestrel. The Raven would rebuild about twice as fast as the Corax, but slower than the Drake. All other things being equal, the Drake, with its large shield capacity and very fast recharge time, would make the best candidate for a passive shield tank.

These cruisers and battlecruisers provide a representative sample comparison of ships by faction.

Faction Ship Type Shield Capacity (hp) Shield Regeneration Time (sec) Average Regeneration Rate (C/T)
CaldariDrake Battlecruiser 5250 1400 3.8
MinmatarHurricane Battlecruiser 4250 1400 3.0
GallenteBrutix Battlecruiser 4000 1400 2.8
AmarrHarbinger Battlecruiser 3000 1400 2.1
CaldariMoa Cruiser 2500 1250 2.0
MinmatarStabber Cruiser 1600 1250 1.3
GallenteThorax Cruiser 1200 1250 1.0
AmarrOmen Cruiser 1200 1250 1.0

The Caldari and Minmatar tend to have the larger shield capacities and higher shield recharge rates. Thus it is not surprising that ships of these factions are more likely to be shield tanked.

Combat Situations

Because a Passive Tank depends on the shield's recharging, it works best in situations where the damage is constant or builds slowly over time. It works least well in situation where the shield will take a large amount of damage in a very short time. Passive tanking can be used, then in situations where the pilot can "kite" the enemies to control how much damage comes in – or in situations where the pilot is using long range weapons and depending on speed to keep away from enemy fire.

In fleet situations the assigned combat role may be a factor. If the ship is to be tackling other ships, for example, its mid power slots may be needed for e-war modules, and it may be exposed to high, brief peaks of damage - so an armor tank will likely be preferable.

Modules and Rigs for Passive Shield Tanking

The following influence the passive shield tank.

Unit Slot Capacitor Drain Effect Notes
Shield Extender mid - Capacity increases Signature Radius
Core Defense Field Extender rig - Capacity increases Signature Radius
Shield Booster mid medium Capacity uses batteries stored in cargo
Power Diagnostic System low low Recharge Rate and Capacity small benefit
Shield Power Relay low - Recharge Rate reduces capacitor recharge rate
Shield Flux Coil low - Recharge Rate lowers capacity
Shield Recharger mid - Recharge Rate small benefit
Core Defense Field Purger rig - Recharge Rate increases Signature Radius
Damage Control low small Resistances limit of one per ship
Shield Resistance Amplifier mid small Resistances stacking penalty
Shield Hardener mid small Resistances stacking penalty
Screen Reinforcer rig - Resistances increases Signature Radius, stacking penalty

Initial Fit

The usual starting point is to try to fill several low slots with Shield Power Relay modules, several mid slots with Shield Extender modules, and to fit all three rig slots with Defense Field Purger rigs. Of course, this will need to be modified to fit slot availability, stacking penalties and other considerations, but it is a good place to start.

Stacking penalties are particularly troublesome. In short, some kinds of modules are reduced progressively in effectiveness if they affect the same attribute. For shield attributes:

  • Penalized: Shield resistances; Shield boost
  • Not Penalized: Shield recharge rate; Shield hit points

The penalty will only apply to the module's impact on the affected attribute, and will progress as follows:

1st mod: 100.0% effectiveness
2nd mod: 86.9% effectiveness
3rd mod: 57.1% effectiveness
4th mod: 28.3% effectiveness

... and so on – the weakest module is penalized first, the strongest is not penalized at all.

With that in mind, although Shield Power Relays reduce capacitor recharge rate, they have no stacking penalties, and they are the most powerful modules in terms of increasing shield regeneration.

Shield Extenders increase the capacity of the shield, and, because recharge time is a constant, this in turn increases the recharge rate. These modules have a Signature Radius penalty associated with them, and they impact on the power grid, but they have no stacking penalties, and their benefits outweigh these costs. In addition, it is often possible to "upsize" Shield Extenders ... putting Large Shield Extenders on a Cruiser, for example, or Medium Extenders on a Frigate.

Finally, Defense Field Purger rigs are almost always more effective than Defense Field Extender rigs in a passive shield fit. The extender increases the capacity of the shield, which does have the effect of also increasing its recharge rate. However, the Purger directly increases the recharge rate by enough to make a difference. The Purger does, however, have a larger impact on Signature Radius.

A tank built from these modules will greatly increase the shield recharge rate, will somewhat increase the shield capacity, will have no stacking penalties, will increase the ship's Signature Radius, and will reduce the Capacitor's recharge time (but will not draw directly on the Capacitor for power).

Possible Alterations

  • Most ships have "damage holes", a type of damage from which they are not well defended. A specific damage type shield hardener may need to be equipped to cover such holes. Hardener modules for other types of damage may be added to account for the primary damage types expected in the encounter. Keep in mind the stacking penalties that arise if a second hardener module is used to alter the same type of damage.
  • If the pilot's skills are not sufficient to install T2 modules, substitutions may be in order. You will have to experiment with T1 modules ... or you may find it better to just wait until your skills improve.
  • Once your tanking modules are set, check to see if your ship's capacitor is stable. If it isn't, and the amount is significant, consider swapping one or two Shield Power Relays for Shield Flux Coils. If you have to swap more than two Shield Relays for Flux Coils, consider putting back all but one of the Shield Power Relays and adding a Capacitor Power Relay.

Full Scale Example: Minmatar Hurricane

Without the use of modules that incur stacking penalties, the calculation for passive shield regeneration rate is multiplicative; the more fittings added, the greater effect each fitting has.

Consider the Hurricane, a Minmatar Battlecruiser.

Minmatar Hurricane shield attributes
  • Base shield capacity: 4250 hp
  • Base recharge time: 1400 sec
  • Average regeneration rate = 4250 / 1400 = 3.0 hp/s
  • Base peak regen rate = 2.5 x 3.0 = 7.5 hp/s
  • Note that the Hurricane's shields are weakest for EM, followed by Thermal, damage.

Why put a passive tank on a Hurricane? As an L3 Security Mission runner:

  • It has good shield capacity and a high recharge rate
  • It has six low slots – 3 for Shield Power Relays and 3 for offensive modules
  • For mission running the mid slots can be dedicated to propulsion and shields
  • Bonuses to medium projectile turrets and six turret hardpoints support artillery for PVE
  • Increases in signature radius matter less in PVE

Shield Power Relays

Shield power relays increase the recharge time directly. They have no stacking penalty, but they do reduce the recharge rate of the capacitor.

shield power relay II attributes
  • Shield Power Relay II
  • Recharge time bonus: -24%
  • No shield support skills
  • (Penalty: Capacitor Recharge Rate -35%)

The first module reduces the Recharge Time by 24%, from 1400 sec to 1400 - 336 = 1064 sec This gives a new Average Recharge Rate of 4250/1064 = 4.0 hp/sec And a new Peak Recharge Rate of 2.5 x 4.0 = 10.0 hp/s

Repeating the calculation:

Modules 1 2 3 4 5 6
Recharge Time 1064.0 808.6 614.3 466.9 354.9 269.7
Peak Regeneration Rate (rounded) 10.0 13.1 17.3 22.8 30.0 39.3

While this illustrates the power of the module, fitting six of them to a ship would be unrealistic. Three modules is a common fit, with the other slots used for other purposes. Thus, with no other skills or fittings, three Shield Power Relays would increase the Peak Recharge Rate to 17.3 hitpoints per second.

For comparison, a medium Phased Plasma projectile does about 18 hp base shield damage plus 24 hp type damage; a medium Lead Hybrid charge does about 10 hp base shield damage plus 16 hp type damage.

Shield Extenders

Shield extenders add hitpoints to the Capacity of the shield. The do not have stacking penalties, but they do increase the Signature Radius of the ship.

large shield extender II attributes
  • Large Shield Extender II
  • Shield Capacity Bonus: 2600 hp
  • No shield support skills
  • (Penalty: Signature Radius 25 m)
Base recharge time: 1400 sec
Shield Capacity: 4250 + 2600 = 6850 hp
Average regeneration Rate = 6850 / 1400 =  4.9 hp/s
Peak Recharge Rate = 2.5 x 4.9 = 12.3 hp/s

The original base Peak Recharge Rate was 7.6 hp/s. So adding a large shield extender increases the recharge rate by 4.7 hp/s; an increase of 62%.

Core Defense Purger Rigs

These rigs produce a percentage increase in Shield Recharge Rate. They have no stacking penalty, but they do increase the Signature Radius of the ship.

core defense field purger rig attributes
  • Medium Core Defense Field Purger I
  • Recharge Rate Bonus: -20%
  • No shield support skills
  • (Penalty: Signature Radius 10%)

Since these are usually the last items to be fitted, this example will build on a fit that includes one Large Shield Extender II and three Power Shield Relay IIs.

The bare ship had:

  • Base shield capacity: 4250 hp
  • Base recharge time: 1400 sec
  • Average regeneration rate = 4250 / 1400 = 3.0 hp/s
  • Base peak regen rate = 2.5 x 3.1 = 7.6 hp/s

After one Large Shield Extender II (see above):

  • Shield capacity: 6850 hp

Three Power Shield Relay II (see above):

  • Modules reduce recharge time @ -24%
  • Shield capacity: 6850 hp
  • Peak Recharge Rate = Shield Capacity/Recharge Time x 2.5
Modules 1 2 3
Recharge Time 1064 808.6 614.3
Peak Regeneration Rate 16.1 21.2 27.9

The Core Defense Purger Rigs impact on Recharge Rate in the same way that the Power Shield Relays do ... by reducing the Recharge Time by a percentage.

Three Core Defense Purger Rigs:

  • Rigs reduce recharge time @ -20%
  • Shield capacity: 6850 hp
  • Starting Recharge Time: 614.3 sec
  • Peak Recharge Rate = Shield Capacity/Recharge Time x 2.5
Rigs 1 2 3
Recharge Time 491.4 393.1 314.4
Peak Regeneration Rate 34.8 43.6 54.4

So with this fit in place, an no pilot shield skills, the Peak Shield Regeneration Rate will be 54.4 hp/sec.

Shield Skills

Shield Management: 5% bonus to shield capacity per skill level

Shield Operation: 5% reduction in shield recharge time per skill level

Any pilot considering a passive shield tank would want to train these to at least Level IV. At that level, their effect would be considerable.

Shield Management @ Level IV

xxxxxxxx

*20% increase in Shield Capacity

This would increase the Base Shield Capacity to: 4250 + 0.20 x 4250 = 5100 hitpoints

It would also increase the benefit of the Large Shield Extender II by 20%: 2600 + 0.20 x 2600 = 3120

Making the total shield capacity: 5100 + 3120 = 8220 hitpoints

Shield Operation @ Level IV

  • 20% decrease in Shield Recharge Time

This would decrease the Base Shield Recharge Time: 1400 - 1400 x 0.20 = 1120

And that value would be used in the three Shield Relay computations followed by the 3 Core Purger Rig computations

  • Relay @ -24%
851.2, 646.9, 491.6
  • Purger @ -20%
393.2, 314.5, 251.6

giving a final Recharge Time of: 251.6 seconds

These two values compute the final Peak Recharge Rate.

Recharge Time: 251.6 sec
Average Recharge Time = 8220/251.6 = 32.7
Peak Recharge Rate:  32.7 x 2.5 = 81.7 hp/sec
If you have come this far, it may be worthwhile pausing to think about what all this might mean. Keep in mind, first, that the shield begins recharging at the Average Rate and then builds towards the Peak Rate, which it only achieves when the shield is 75% gone. That means that these numbers are not very helpful in combat, they simply give a way of comparing a passive fit against a more active one, or against armor.

Passive fits more or less assume that you will be kiting, or at least firing from longer range, and that by so doing, you will not come under intense bursts of heavy fire. In other words, the shield needs time to rebuild itself as you fight.

The advantage of this approach lies in its avoidance of stacking penalties, which gives you more benefit per module fitted, and which in turn should give you extra strength in areas other than defense. This may come from having room to fit an additional module, or by savings in power or CPU that let you install more highly rated equipment.

Final Fit

Thus, a Minmatar Hurricane fitted for this particular skilled, passive tank would have a Peak Shield Regeneration rate of approximately 82 hp/sec. Again, for comparison, a medium Phased Plasma projectile does about 18 hp base shield damage plus 24 hp type damage; a medium Lead Hybrid charge does about 10 hp base shield damage plus 16 hp type damage. A complete fit might look like this:

PvE T2 Passive Shield Tank
Hurricane: PvE T2 Passive Shield Tank
EFT
[Hurricane, PvE T2 Passive Shield Tank]
650mm Artillery Cannon II
650mm Artillery Cannon II
650mm Artillery Cannon II
650mm Artillery Cannon II
650mm Artillery Cannon II
650mm Artillery Cannon II
Rapid Light Missile Launcher II

10MN Afterburner II
Large Shield Extender II
EM Ward Field II
Thermal Dissipation Field II

Shield Power Relay II
Shield Power Relay II
Shield Power Relay II
Gyrostabilizer II
Gyrostabilizer II
Gyrostabilizer II

Medium Core Defense Field Purger I
Medium Core Defense Field Purger I
Medium Core Defense Field Purger I


Hobgoblin II x6

Republic Fleet Phased Plasma Mx1
Caldari Navy Inferno Light Missile x1

Fitting template high slot label.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
Fitting template mid slots label.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
Fitting template low slots label.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
Fitting template subsystem slots label.png
Fitting template drone slots label.png
icon?size=64&.png
Fitting template drone slots label.png
Fitting template charge slots label.png
icon?size=64&.png
icon?size=64&.png
Fitting template rig slots label.png
icon?size=64&.png
icon?size=64&.png
icon?size=64&.png
FITTING DIFFICULTY
EVE VERSION
RET 1.1
ALPHA CAN USE
UNSET
EFT
SKILLS
NOTES
RECOMMENDED SKILLS
  • Minmatar Frigate IV
  • Minmatar Cruiser III
  • Spaceship Command IV
  • Minmatar Battlecruiser II
  • Gunnery III
  • Sharpshooter IV
  • Small Projectile Turret V
  • Small Artillery Specialization IV
  • Capacitor Systems Operation V
  • Capacitor Management IV
  • Power Grid Management V
  • CPU Management V
  • Electronics Upgrades V
  • Long Range Targeting IV
  • Signature Analysis IV
  • Medium Projectile Turret V
  • Medium Artillery Specialization I
  • Missile Launcher Operation V
  • Shield Upgrades IV
  • Tactical Shield Manipulation IV
  • Afterburner IV
  • Energy Grid Upgrades IV
  • Target Management V
  • Advanced Target Management I
  • Navigation IV
  • Evasive Maneuvering III
  • Warp Drive Operation III
  • Hull Upgrades IV
  • Shield Management IV
  • Mechanic V
  • Gunnery V
  • Rapid Firing IV
  • Motion Prediction IV
  • Trajectory Analysis IV
  • Weapon Upgrades IV
  • Mechanic III
  • Jury Rigging III
  • Shield Rigging I
  • Scout Drone Operation V
  • Drones V
  • Gallente Drone Specialization I
NOTES
  • This is a passive shield tanked PvE fit suitable for L3 Security Missions
  • The mid slot hardeners should be swapped to match the damage type appropriate to the enemies the pilot expects to encounter.
  • With one shield hardener running, the capacitor is stable. A second hardener will run the capacitor down in about fifteen minutes.
  • If skills are insufficient for power, consider swapping a gyrostabilizer for an Auxilliary Power Control.
  • This is a highly skilled fitting. Weapons and modules can be scaled back to meet pilot skills. Watch dps and shield recharge rate and try to balance the decline.
  • The mid slot hardeners should be swapped to match the damage type appropriate to the enemies the pilot expects to encounter.
  • With one shield hardener running, the capacitor is stable. A second hardener will run the capacitor down in about fifteen minutes. Since this fit is intended for L2/L3 Security Missions, that should not be a problem. If it becomes a concern, consider replacing one of the low slot gyrostabilizers with a Capacitor Flux Coil.
  • Low slot modules can be replaced by Auxiliary Power Controls, Capacitor Flux Coils, and/or Power Diagnostic Systems as needed.

More Example Fits

Certain ships are often fit out with passive tank. Rather than copy those fits here, this article links to their Wiki pages, where you can see the full information, including a sample passive shield fit, for each ship.

  • Caldari Drake: battlecruiser - level 3 mission runner, wormhole pve explorer
  • Caldari Caracal: cruiser - level 2 mission runner
  • Gallente Myrmidon: battlecruiser - level 3 mission runner
  • Minmatar Rupture: cruiser - level 2 mission runner
  • Minmatar Stabber: cruiser - level 2 mission runner
  • Minmatar Rifter: frigate - level 1/2 mission runner