Skywatcher 17 Amp Power Tank

[Taff]

Hi' Do anyone use a Skywatcher  17 Amp Power Tank with their scope and mount.If so how long does the power last for until it needs charging up again.Thanks for looking.Mark

[teoria_del_big_bang]

In it's simplest terms this battery should give you an average of 1 amp for 17 hours, or 2 amps for 8.5 hours and so on. In reality not so simple as even the rating can depend on what current draw the manufacturer bases the rating.

Also in practice it is probably not straight forward. For instance you should not fully discharge it during use or it will not fully charge again, I have seen advice about only discharging to 50%, although not sure this is true. Also the temperature will have a big effect and if used in very cold weather this will reduce the time it will last, and obviously depends what you are running on it.

The current from the mount will depend on the mount and to some extent how heavy the scope and other equipment is, especially if not balanced correctly. The general figures banded about for a HEq5 I think is about 1.6A for slewing and 0.9A for tracking.

So if only using the mount then with an average of say 1 amp you should get in theory 17 hours use, but not discharging it fully probably more like 9 hours use.

If also using dew heaters then this will reduce as each heater probably takes 0.3 to 0.5 A all depends on size and temperature but they are obviously a significant draw.

So I guess after all that rambling on my answer is I do not know but IF you only have the mount and say a camera and one heater (so say average 2 amps) then I would think you would easily get 5 hours, could well be a bit more but would not bank on it without discharging it too much.

 Also always put it on trickle charge after a session to fully recharge again and also if you have a long period not using it just get it out and trickle charge it now and again.

Steve

[wornish]

With two dew heaters and my cooled camera, guide cam and mount all running I get about 3 - 4 hours use before the mount starts to complain about low voltage and doing funny things.   Of course it could be my wiring but I don't think so.

I have recently assembled my own waterproof 12V power supply in a box and that is connected to the mains for doing longer runs. That said,  chance to do a long run would be a great thing if the clouds would just stay away.