Topic: Running two thing off 1 sla

[Swampy]

So, this is the equation to calculate battery time:

( Battery Capacity [mAH] / Current Draw [mA] ) * ( .80 )

If I want to calculate the time with two things running off one batt, should I just add their current draw??? So, if my dat draws 200 and my pre draws 500, Id just put 700 as my current draw in the equation. Would that work??? THANKS!

[Brian Skalinder]

So, this is the equation to calculate battery time:

( Battery Capacity [mAH] / Current Draw [mA] ) * ( .80 )

If I want to calculate the time with two things running off one batt, should I just add their current draw??? So, if my dat draws 200 and my pre draws 500, Id just put 700 as my current draw in the equation. Would that work??? THANKS!

Yeah, that'll give you a good rough idea.  Keep in mind the AH ratings on SLAs are based on a slower discharge rate than our typical usage.  Generally speaking, the faster the discharge rate, the less efficient the usage of the existing capacity, therefore the shorter the run-time.  But 700mA isn't real high, unless you're talking about a very small capacity SLA.  You should be just fine.

What are you looking to run off the same SLA?

[Swampy]

THanks Brian. A DIMC-20 and a D8

[Swampy]

700mA isn't real high, unless you're talking about a very small capacity SLA.  You should be just fine.

Do you think 4.5ah is too small... If my calculations are correct, it would run the dmic and d8 for 5 hours...

[F.O.Bean]

700mA isn't real high, unless you're talking about a very small capacity SLA.  You should be just fine.

Do you think 4.5ah is too small... If my calculations are correct, it would run the dmic and d8 for 5 hours...

alex, all you had to do was ask me, i ran that for 4 years or more......

i could get about 7 hrs max out of that setup(dmic + d-8), ive never pushed it to die, so you could prolly get 8 hrs if ya tried, but i cant say for sure......you can easily get 2 phish shows(about 3 hrs a piece)

[Swampy]

cool! thank bean. You ran it with a 4.5 ah?

[heath]

you can run that d8 for like 15+ hours with a simple d-cell sled...i can make you one if you like....the one i made for my m1 is a life saver!!

[greenone]

I may actually end up running *three* things off one SLA - ADC-20 and D8 through wall wart-type connectors (what are those things called?), and my V2 off a regular 4-pin XLR. My SLA came with a Y cable that splits into two female 4-pins, and I'm checking with Ed at Kindkables to see if he'll sell a 4-pin to double-wall wart separately from the SLA he sells. If he does, I'll post here for the non-soldering folk.

I do have a separate D-cell sled but I don't think I can power my whole rig off it or I'd give it a shot. They're very cool though - Heath is right in that they last FOREVER. Mine usually go over 20 hours though 15 is a safe swapout point. Actually just got some rechargeable D-cells for Christmas because I got tired of buying and tossing non-rechargeables...

--Dave

[F.O.Bean]

cool! thank bean. You ran it with a 4.5 ah?

thats a 6v 7.2a batt i was talkin about!!!

[Swampy]

Ahhh, see, what Im concerned about its, Brian said "700mA isn't real high, unless you're talking about a very small capacity SLA" Im wondering if 4.5 is too small of a capacity, because mathmaticly, it should power a d8 and a dmic for 5 hours... So, I just want to make sure it works!

[F.O.Bean]

Ahhh, see, what Im concerned about its, Brian said "700mA isn't real high, unless you're talking about a very small capacity SLA" Im wondering if 4.5 is too small of a capacity, because mathmaticly, it should power a d8 and a dmic for 5 hours... So, I just want to make sure it works!

only one way to tell, recreate the concert experience as much as possible at home, and drain that batt once.....i dont recomend draing batts too many times, but it wont hurt to test to see how long she can go!!!

[Tim]

you can run that d8 for like 15+ hours with a simple d-cell sled...i can make you one if you like....the one i made for my m1 is a life saver!!

that's a lot of batteries to be throwing away... $$$ and environmental unfriendly.

[heath]

rechargeable d cells, baby!

[Chuck]

Alex:
Another thing to keep in mind is, ideally, don't ever totally drain a SLA battery. They don't always bounce back too well from a deep discharge. It can affect how well it will hold a charge in the future.

Welcome to team "Back Breaker."
I'm right there with you buddy. I carry (2) 12v SLA's.