Heat loss..short circuit...as near to perma as poss

Well, the recharge cap is 400%: http://paragonwiki.com/wiki/Limits
So 6m/(1+4)=1.2 minutes = 1 minute 12 seconds

The debuff lasts for 30 seconds so that 42 seconds of down time + the activation time or 44.17 seconds down for every 30 seconds up.

However, you won't be able to reach the 400% recharge cap without external buffs.

The rech cap is actually 500%, +400%, but we start with 100% for the purposes of figuring things out.
360/5 = 72 seconds at cap.

As mentioned I have an ill/cold with it at 94 ish seconds, which once you factor in cast time and a quick repositioning gives it a 7-8 second downtime. For the buff of course, not the debuff.

That is actually a staminaless build (or at least the last version I made of it is) and it works very well. The toon burns way more end than a cold/elec ever could (short of nuking) and I figure I could get by with about 15 seconds total downtime of HL and still not feel the pinch for stamina.

The highest build I've managed has it at 89.xx seconds, but it sacrifices a few set bonuses that I didn't want to lose.

Of course all that will change now that stamina is becoming inherent.

edit: the debuff itself is at best up about 1/3rd of the time

-Frosticus

Two different ways of thinking about recharge. I tend to use the 400% rather than the 500% (including the base recharge), since I think it makes the recharge formula:

Recharge_Time = Base_Recharge/(1+Recharge_Modification)

eassier to understand... rather than using the formula

Recharge_Time = Base_Recharge/(Recharge)

but use whatever works best for you. Regardless it boils down to the same 1 minute 12 second recharge + activation time.