Im with you there Mark, only issue is some people cry if they hear a mosquito farting 300m away on dark sky camps........ I know they are quiet but yeah ive been stung before! Genny during the day, battery by night plenty of redundancy if all goes to pot
Battery life is, as John has implied, a function of depth of discharge.
Discharge fully and you'll get less cycles before the battery is worn out, lighter discharge will result in a longer service life.
The single most important thing is to fully charge the battery immediately (within a day or so) after any discharge and don't pump high current in to the battery if it's in a low state of charge. Equally important is to maintain the correct electrolyte level, if the level falls below the top of the plates due to overcharging the life of the battery will suffer.
If you leave the battery in a discharged state for any longer than a couple of days the sulphate formed from the discharge process will harden and recovery is difficult if not impossible.
Another factor not usually considered is the care that the battery has had before your purchase, self discharge on deep cycle batteries is around 5% per month, a new battery left on the shelf for months could be in a sulphated state before you even buy it.
Another misconception regarding stat of charge is battery voltage, as a rough guide 12 volts with no load represents 50% discharged, 11 volts is pretty well dead flat.
Very well articulated Paul.
Batteries and charging etc,is a very important topic,that one has to try an gain some knowledge on.Many of these outdoor hobbies such as camping,hunting,and astronomy are so much more enjoyable when good battery gear and charging gear is bought,and most importantly looked after properly.As has been mentioned-you get what you pay for.\
Go to a dedicated battery shop,such as 'battery world' or similar,and find a proper sales person who knows what they are talking about.I have been lucky and found a very helpful person in kingaroy battery world (he's keen on astronomy-so picked my brains to buy gear,so this has helped alot).
Buy a proper battery charger,not some crap thing from cheap auto shops.Spend between $200-$300 on one,either Ctek,or projecta.
I bought a $250 Projecta one-it has screen you can toggle through see what's going on.Also talk to dumpies,occasionally they get batteries in the might be reasonable-I got this 97amp deep cycle battery from tip,looked clean and not old,had it tested,the battery guy said it was in very good order-I've used it to power my engal for camping and dew heaters.However,on long term trips,I'll spend the money on a 120amp hour AGM.
A good AGM 120 amp battery will cost $320 along with a good charger $200 plus-worth the money.
Maybe IIS should have a battery 'sticky' Pauls advice is very good,over on hunting/fishing forums they have battery/power sticky.I've noticed some here think they can get get out off power supply issues cheaply-it just does not work.I've done a lot of research into it,and its paying off in my field trips
Even the cable in image here cost $50-proper socket for fridge.fuse,all heavy duty.If you spend $1000 plus on a fridge/mount whatever,spend a proportional amount on fittings.
I only use the battery for powering my mount and auto guider
NEQ6 Pro Mount about 2ah. SG-4 needs about 200 mi.ah. (2.02ah)
So if you use the 40ah/10hr battery for 10 hours @ 2.02amps it will be 50.5 % discharged
Therefore if you use the battery for an average 5 hours a night 5 hours @ 2.02amps it will be 25.25% discharged
That should only be your Maximum usage ever!
Thats a lot of current draw ? I have a meter to monitor battery use , mount uses about .5A tracking , All up with camera ,mount , focuser and fans every thing going I draw about 3A tops. Even laptop only uses 0.9 after boot up I total 5Ah use after 7hr running the laptop.
AGM will discharged lower than 50% as well . The spec sheet for mine say good for >1400 dischages to 10v , they are designed to go much lower than your normal battery , thats what you are paying the extra for.
Mark
Quote:
Originally Posted by GrampianStars
NEQ6 Pro Mount about 2ah. SG-4 needs about 200 mi.ah. (2.02ah)
So if you use the 40ah/10hr battery for 10 hours @ 2.02amps it will be 50.5 % discharged
Therefore if you use the battery for an average 5 hours a night 5 hours @ 2.02amps it will be 25.25% discharged
That should only be your Maximum usage ever!
Im with you there Mark, only issue is some people cry if they hear a mosquito farting 300m away on dark sky camps........ I know they are quiet but yeah ive been stung before! Genny during the day, battery by night plenty of redundancy if all goes to pot
Yep, I used to take a genny camping and it never really bothered me.... I would let the tank run dry thru the night and then it was just me, the campfire and the stars... that was when I began to appreciate the total lack of noise.
Hence my move to a solar setup. No power issues and zero noise. Was cheaper than a genny too, for me anyway
Sounds like you've purchased wisely Ken. A mount and guider shouldn't draw more than 1amp, unless you're slewing all of the place continuously (which usually isn't the case for imagers).
Max discharge down to 33% gives you 26ah, which should give you at least 2 very long nights of imaging. Recharge as soon as you can, and trickle top up from time to time. Sounds like you already have a good charger which is very important.
I've bought from Aussie Batteries before with no probs at all. You can always buy an extra >100ah 2nd battery in the future if you start running dew heaters, laptops and other juice hungry beasts!
Last edited by RobF; 18-05-2012 at 07:26 PM.
Reason: language/spelling
As an example of battery powering a telescope I have a LX200 classic that I use for school nights and other displays. The telescope operates in alt/azm mode. Sessions usually run between 2 and 3 hours.
I have used a 12v 18 AH battery that was discarded from my golf buggy due to poor capacity 4 years ago after two years use. It gets charged up when I want to use it. It has never failed to last the distance for this use.
Great thread and input from everyone. Very timely for me.
I'll be heading out to Leyburn again each month after several years hiatus. I have equipped myself with a 2nd 12inch LX200, spare SXVHR9 and all the other bits I needed to do my SN search once a month from there - ok an extravagance, but like government policy why pay for one when for twice the price you can have 2, at least that way the home observatory stays intact.
I have bought a new Full River 85amphr/20hrs deep cycle battery and a Jaycar 600w full Sine wave inverter. This will power the LX200, The Starlight camera and my Toshiba laptop. The dew zappers will run directly 12v from a 55 amphr battery.
Can someone confirm that the LX200 will use about 1amphr (doing say 300+multiple short slews). The SXVHR9 is rated at 1amphr or less and the lappy about 6.5 amphr. So over say 7 hours that would be 8.5amp draw per hour so I should get a night out of it without draining the battery too low. Then when I get home within a few days fully recharge the battery and this will prolong its service life.
Thanks
The LX200 will probably work OK directly from the 12volts without the inverter and AC supply. All the ones I have worked with do. This may save a few watts. Try it first. They do slew a little slower on 12volts but that is not usually a problem.
You really need to stick an ammeter or multimeter in the circuit to see what you're drawing Peter. I did experiments with my laptop in all sorts of states, imaging, slewing etc before buying an extra battery to get my by 2 nights at Leyburn. Camera draw depends a lot on how hard you're pushing cooling too of course. I don't routinely run dew heaters - they can be hungry for juice and pretty essential for an SCT.
Peter the using of a 600w inverter is a very inefficient way of powering it all it won't take too long to kill an 85Ah battery with a 600w inverter, it's overkill for what you're powering. I would of gone down the DC to DC route a far more efficient means.
BTW the Full River AGM is an intelligent buy, one of the best AGM's out there. Deep Cycle batteries aren't all equal.
Quote:
Originally Posted by PeterM
Great thread and input from everyone. Very timely for me.
I'll be heading out to Leyburn again each month after several years hiatus. I have equipped myself with a 2nd 12inch LX200, spare SXVHR9 and all the other bits I needed to do my SN search once a month from there - ok an extravagance, but like government policy why pay for one when for twice the price you can have 2, at least that way the home observatory stays intact.
I have bought a new Full River 85amphr/20hrs deep cycle battery and a Jaycar 600w full Sine wave inverter. This will power the LX200, The Starlight camera and my Toshiba laptop. The dew zappers will run directly 12v from a 55 amphr battery.
Can someone confirm that the LX200 will use about 1amphr (doing say 300+multiple short slews). The SXVHR9 is rated at 1amphr or less and the lappy about 6.5 amphr. So over say 7 hours that would be 8.5amp draw per hour so I should get a night out of it without draining the battery too low. Then when I get home within a few days fully recharge the battery and this will prolong its service life.
Thanks
Great thread and input from everyone. Very timely for me.
I'll be heading out to Leyburn again each month after several years hiatus. I have equipped myself with a 2nd 12inch LX200, spare SXVHR9 and all the other bits I needed to do my SN search once a month from there - ok an extravagance, but like government policy why pay for one when for twice the price you can have 2, at least that way the home observatory stays intact.
I have bought a new Full River 85amphr/20hrs deep cycle battery and a Jaycar 600w full Sine wave inverter. This will power the LX200, The Starlight camera and my Toshiba laptop. The dew zappers will run directly 12v from a 55 amphr battery.
Can someone confirm that the LX200 will use about 1amphr (doing say 300+multiple short slews). The SXVHR9 is rated at 1amphr or less and the lappy about 6.5 amphr. So over say 7 hours that would be 8.5amp draw per hour so I should get a night out of it without draining the battery too low. Then when I get home within a few days fully recharge the battery and this will prolong its service life.
Thanks
Good luck with the search Peter-you might meet up with David Trappet-he use to come up here.
As mentioned going with the sine wave inverter will really chew you battery,a DC option would be good.
Yes,quite a useful thread,its one of the major topics on camping and outdoor forums,I am surprised we have not had a thread like this here,its a good one.
What's did the 'full river' battery cost Peter-looking at buying a 120 amp AGM soon,looking at different options.
Im with you there Mark, only issue is some people cry if they hear a mosquito farting 300m away on dark sky camps........ I know they are quiet but yeah ive been stung before! Genny during the day, battery by night plenty of redundancy if all goes to pot
Thats easily fixed Brenden, tell them to get stuffed . Bet they will be around in the morning wanting to get batteries recharged.
Thanks John and Chris.
I guess my ignorance of DC had me concerned when I read somehwhere about potential problems for the laptop from having multiple DC connected to the battery. The DC is an option as I have cables and input for dc to the battery.
Chris have sent you pm re the Full River.
John wont the scope etc only draw what it needs from the inverter, I am ignorant on how it will flatten the battery quicker.
Peter
Thats the issue. they aren't astrophotographers stay up till 1am max and then pike! anyhow i have a big battery now and another one should be on its way within a month.
Quote:
Originally Posted by marki
Thats easily fixed Brenden, tell them to get stuffed . Bet they will be around in the morning wanting to get batteries recharged.
they aren't astrophotographers 
