highflyer1968
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I'm using this battery for my MPR launches. Will this be ok for H and I motors?
Is this a good battery
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I'm using this battery for my MPR launches. Will this be ok for H and I motors?
bobkrech
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It's fine for anything. You can launch all day with it.
An 8 AH battery has a capacity of 8 AH x 3600 S/H = 28800 AS. Estes igniters has a resistance of ~0.8 ohms so at 12 volts you use I = V/R = 12 /0.8 = 15 A. If you push the button for 2 S every time you launch you use 15 A x 2 S = 30 AS per launch. The number of launches you can make on 1 charge is 28880 AS / 20 AS/launch = 960 launches. Way more than you can fire from 1 or 2 pads in a day. If you're using 1.6 ohm e-match based igniters, the current is halved so the possible launches double. I'm not counting the steady current draw of continuity LED's but if you had 5, you average current is 0.1 A so for each hour of operation you draw 360 AS which would equal 360 AS /30 AS/launch = 12 launches per hour, again a negligible number.
If you have a PA systems, run that off a separate battery as they can easily draw over an amp.
Bob
An 8 AH battery has a capacity of 8 AH x 3600 S/H = 28800 AS. Estes igniters has a resistance of ~0.8 ohms so at 12 volts you use I = V/R = 12 /0.8 = 15 A. If you push the button for 2 S every time you launch you use 15 A x 2 S = 30 AS per launch. The number of launches you can make on 1 charge is 28880 AS / 20 AS/launch = 960 launches. Way more than you can fire from 1 or 2 pads in a day. If you're using 1.6 ohm e-match based igniters, the current is halved so the possible launches double. I'm not counting the steady current draw of continuity LED's but if you had 5, you average current is 0.1 A so for each hour of operation you draw 360 AS which would equal 360 AS /30 AS/launch = 12 launches per hour, again a negligible number.
If you have a PA systems, run that off a separate battery as they can easily draw over an amp.
Bob
rcktnut
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That battery will serve you well. I have a 20 year old 12V 7AH same type, different brand that is still going strong. I have lit K motors with 200ft. of cord, no relay without a problem.
Ditto Bob's post: I've been using similar 7, 7.2 & 8 amp/hr 12V Gel-Cells for personal launching for more the 25 years. Every thing from single motor to 6 motor clusters(on a fresh charge).
I just recently purchased a new Hobbico 12V 7 amp/hr battery for another non-Rocket application they are great for just about any limited amp use. .
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