View Single Post
Old 16-07-2020, 12:54 PM
The_bluester's Avatar
The_bluester (Paul)
Registered User

The_bluester is offline
Join Date: Feb 2011
Location: Kilmore, Australia
Posts: 2,794
I reckon a good rule is to work out what you need, add 30% fat. Then double it.

I know from experience of forgetting to turn on my DC supply one night that a 7.2AH battery in good temperature conditions will run my rig of Orion Atlas mount, cooled ZWO cam, guide cam, focuser, heater for a small refractor and small PC for about half an hour. It would be drawing at least double what the Dob would, so call that an hour or so (Probably more with the lower discharge current) so I would guess 18AH might reliably get four or five hours running a dob for visual if you don't need heaters?

That really is a back of the napkin guess, but you don't want to be over discharging an SLA battery on a regular basis or it will drop off in capacity pretty quickly.
Reply With Quote