SynScan AZ goto - current draw - rough data

[Eigen]

Hello,

I have been contemplating a minimum power supply for the mount, which would enable max. portability, I did some quick preliminary measurement of the current draw that can be expected from the mount to see whether a 7Ah source would be sufficient for a decent observing session.

Test was done on an 80-90% 7Ah dry battery, roughly equivalent to what is found in the powertanks. OTA was a 127 mak.

Approx current draws as follows:

Idle: roughly in the 100 ma range

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Finding object, goto phase.

Slew one axis, max speed: a bit below 200 ma

Slewing both, max speed ~250 with a peak of 300ma on initialization.

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Centering, observational adjustment on single stellar object

Depends on speed etc. general rule of thumb would be 100-150ma

Anyway, hope this helps anyone interested in the figures, if anyone needs a more detailed test/examination of a particular situation, feel free to ask. As for me, I think 7Ah will be more than sufficient for a decent cloudless night.

Regards,

Eigen

[Steve Ward]

I found that my SW 7ah Powertank was good for only 3-4 hours in the winter time , assume they don't like the really cold conditions .

Bought a regulated mains supply as there's nothing more frustrating than a dying power supply in the middle of the night.

[S.A.M]

Hello Elgen,

Excellent information about minimum requirements for GOTO mount, I use a car jump starter battery for my EQ6 and it lasts a very long time. Only thing I could not figure out was the statement about 'decent cloudless night', what is one of them

Peter

[Eigen]

I found that my SW 7ah Powertank was good for only 3-4 hours in the winter time , assume they don't like the really cold conditions .

Bought a regulated mains supply as there's nothing more frustrating than a dying power supply in the middle of the night.

Thanks for the info, it is indeed the cold that I am most worried about, as you suspect a cold ambient can wreak havoc on the batteries ability to supply current.

What sort of mount/ota were you using, same as my portable setup?

Ah, a decent cloudless night you ask of?...some might call the creature the Nessie of the astronomy world, often spoken off and claimed by many, but never really shown to have actually manifested itself outside the imagination.

Regards,

Eigen

[Steve Ward]

It's running an HEQ5ProSynScan ,

I do use it for short away trips with the EQ3-2 but as I generally operate from home the mains option is best for me.

I do have one dark site nearby (home site's pretty good) that I use on occasion , but this has mains available for me to use if i'm running scope , camera and computer.

Generally though it's too much faff at the moment to travel with the unpredictable weather , I can sit and look at clouds from home....