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Old Mar 19, 2003, 10:09 PM
Registered User
Kings Park, New York, USA
Joined Sep 2001
813 Posts
How do you measure Static Amps? Within 5 seconds of a fresh charge or?

How do you measure Static Amps?

For instance Astro Bob told me to prop static for no more than 18 amps. is that 18 amps for the first few seconds on a fresh peaked pack, or after 10 or 15 seconds or after 30 seconds or 45 seconds?

I have a AF020 7T with a superbox.


Anyway with 8 CP1700SCRs and a 11x8 Graupner cam Folder

On a fresh pack i get 20.8amps static for a very short time

After 15 or 20 seconds down to 17.7 amps and goes lower from there.

Thanks
Ron Parigoris
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Old Mar 20, 2003, 02:47 AM
Registered User
N. Staffs, UK
Joined Jan 1997
5,654 Posts
In terms of the value that the motor can stand, I usually count it as the current after around 30 sec running. It will stay close to the value for most of the run. It's a bit tricky to measure though because I don't like to run the system for much more than 30 sec static (i.e. with no air cooling etc) so I have to be quick .

The absolute peak value for a second or two on a freshly charged pack isn't really of much interest.


Steve
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Old Mar 20, 2003, 09:39 AM
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Fredrik W's Avatar
Stockholm, Sweden
Joined Jul 2002
1,249 Posts
When I do my motor tests I start take readings after 1/6 of the batterys capacity has been used. This to avoid the initial peak of the pack.

// Fredrik Wergeland
Sweden
www.flyingmodels.org
The Great Electric Motor Test
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Old Mar 20, 2003, 10:30 AM
Space Coast USA
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Space Coast
Joined Oct 2000
20,698 Posts
You can always let the battery sit overnight before testing...or

You can run the motor at 1/2 power for several minutes before testing at full power......or

If you have some foam cutter wire, you can bleed off some of the battery energy by using a 12-18" piece of that wire across the battery terminals.

It takes about 1 min of full throttle to get the battery on the "level" part of the discharge curve.

From your description, looks like you are OK. Remember, a hot battery, hot off the charger, can put out quite a bit of juice for a short time as compared to a cool battery that has set for awhile.

hoppy
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