12v power supply

[terry67]

hello.....i have an eq6 mount and am looking for a 12v power supply

i have read that some of you designed your own or is the skywatcher powertank any good

any advice is appreciated 

thanks terry

[messiermark]

hello terry

i use a large leisure battery,  very easy to charge even with solar panels if you want to go to atsrocamps, don't get car battery or some jump packs because they don't like being totally drained and recharged  

[Tinker1947]

If you have mains power then a Maplin/FLO PSU works well, just have a long low voltage cable outside....

http://www.firstlightoptics.com/power/maplins-xm21x-7a-138v-regulated-mains-power-supply.html

[terry67]

hi...ok the power supply is so i can go to dark sites to do obseving

[Pyrodave]

+1 for a leisure battery, I've had 3 so called power packs and every one has failed after a few months 

[ronin]

You will really need a bigger battery then the power tanks that are often used.

Reason is simply that these use a small lead acid battery and will drain easily, once drained they are damaged and you can easily find you need a new one all over again.

Not helped by the fact that we tend to use the power tank until it is unable to drive the mount, then we pack in and go home. Bit the power tank is drained too much.

The leisure batteries are designed differently and are for a long slow drainage, they may also need a trickle charger not a normal car charger.

One option is visit Maplins and get one of their DC adaptors for a car, set it to 12v and run the scope from the car battery. Just make surte the car battery is not on it's last legs. You could leave the car running while observing - nice warm car, somewhere to sit and store stuff. Just arrange yourself away from the exhaust. I do this with the car running as I have a 12v kettle and it means I can heat water for a hot drink, and as I say use the car for keeping stuff in (less to pack up at the end).

[cosmological]

I've used a jump start for years and had no problems with it, I always make a point of keeping it topped up.

[matteboy]

Definite yes on the leisure battery, I bought a 110ah one, from a caravan place and it should last for ages!  You do not want to be carrying it too far though unless, of course, you're training for world's strongest man! 

As mentioned above you really want a long slow drain, a normal car battery needs to give massive amps in a short period of time to turn an engine over, same with the 'jump-packs' but the leisure batteries are designed to run TVs and fridges in caravans so should be good for supplying a long reliable continuous power at low amps.  A good charger is a good investment too, helps if you run the battery too low.  They do need to be charged after every use, but I think that applies to any of the power supplies you can use.

[oldpink]

problem with power tanks & battery's is they take for ever to charge and when they run out thats it
I have a small camping generator that does 240 & 12v and more than enough to power everything on one tank of petrol (4L) for 5 - 6 hrs
and its pretty quiet I stick it out the way with a 30ft extension, should be ideal for the scope & laptop, paid £80 new with a 2 year warranty 
that was 4 years ago and its never let me down

Oh came in handy when a muppet from the council put his JCB through the main power cable to out block
and we had no mains for 16 hrs in Nov
Mrs didn't miss corry & eastenders, that would have been a major issue
 

[ChrisLX200]

For use at home I bought a 30A 12V PSU and, more recently, some armoured cable which I'll run out to the pier for a permanent installation. For portable I use a power tank - a larger one then normal having a 34A battery. The power tank is fine unless I use the dew heaters full blast which does tend to flatten it after 8hrs or so (found that out recently!).

ChrisH

[sloz1664]

If you are flush with cash and don't want to suffer from a bad back try one of these:-

http://www.lithium4golf.com/golf-batteries/golf-36-hole-24ah-lifepo4-battery.html

Steve

[Owmuchonomy]

I wouldn't go near a power tank for serious use.  They have very limited lifespan and energy output.  You could use a caravan/boat deep cycle leisure battery like ours.  110AH gel type.  Gel because you can't spill the contents and it is 'fume' safe for enclosed use. However, they are VERY heavy!  If you use dew bands just make sure you get a decent voltage regulator or fused cable.

[ChrisLX200]

I mentioned earlier I have a 30A 12V supply I intend to use for powering my rig, it is of good quality and the output voltage is tunable/adjustable. So I was wondering what voltage to set it at? 12.0V might be the obvious answer but then ordinary batteries tend to work at 13.8V, and some electonics hate under-voltage even more than over-voltage. So what voltage - 12.5, 13.0.... 13.8?

ChrisH

[oldpink]

anything from 11 - 15 volt will work, its more about a constant Amp rating
my EQ5 requires 2 Amps to work according to the manual, I tend to use a 12v 3A power supply from an old 15" tv thats ideal 

[Davey-T]

If you are flush with cash and don't want to suffer from a bad back try one of these:-

http://www.lithium4golf.com/golf-batteries/golf-36-hole-24ah-lifepo4-battery.html

Steve

+1 for Lith-ion battery, I use a 40ah one and it runs mount,dew heaters, cameras etc all night in winter and hardly makes a dent in it, recharges in minutes with supplied 10ah charger and most importantly as far as I'm concerned weighs no more than  a 17ah L/acid power pack so you don't need a troupe of bearers to carry your gear across the fields for you

Dave

[terry67]

ok thanx guys some useful tips,,,,now to start searching

thanks terry

[Astral Enigma]

Guess my starting question is the same - not sure what to get to run my 925 VX GEM and Nexstar 6SE - former is quoted as needing 3.5A. For now at least it will mostly be at home so running off the mains is simple and lots of you seem to suggest power tanks can be risky because they can easily go flat - over OR under use - and then just die, although the suppliers I've talked to see it as not much of an issue.

Has anyone used the Baader 12v 5A supply? Or this HiQ supply from Opticstar ? A few cpeople have mentioned Maplin's XM21X 5A supply too. If so, any thoughts?

Of course, a Celestron or SW power tank has more outputs that may come in handy one day - are they actually identical, but SW is generally cheaper ?

Finally (for now!) I believe I heard/saw Celestron's warranty is invalidated if not used with an approved supply, and I've got two nice new scopes ....

[GuillermoBarrancos]

I bought this set from TS along with the N EQ6 Pro order back in february.

http://www.teleskop-express.de/shop/product_info.php/info/p5805_TS-Powerset---12V-12Ah-battery--charger-and-adapter-in-a-useful-shoulder-bag.html

Leisure batteries are best to use, next to the new Li-Po batteries, like these:

http://www.firstlightoptics.com/power/tracer-12v-10ah-lithium-polymer-battery-pack.html

Li-Po batteries are being used in the RC hobby for years. So it´s nice to see them finally make an entry in the Astro hobby.

[mitchelln]

You might like to consider one of these 14Ah Deben lamping batteries:

http://www.huntingsolutions.co.uk/battery-belt-pack-12v-14-amp-hr-1571?p=12_32

It even has a cigar socket on it. Avoid the SW powertank. It is a lot of money for what you get.

Best choice is a Lithium Polymer. Nice and light I've just got a 14Ah Deben Tracer and reviewed it on this thread:

http://stargazerslounge.com/topic/213924-deben-tracer-14ah-lipo-battery/

Pretty expensive though, but does the job very well.

[Tinker1947]

Here is what i use, maybe should have just got a 30amp 13.8v supply to start with, but never thought i would need more than one.....

[Hootsitabernacle]

Here is what i use, maybe should have just got a 30amp 13.8v supply to start with, but never thought i would need more than one.....

I take it you use the maplins power pack to run your scope?..amongst other things...

[Tinker1947]

the one on the left runs the scope the other leads goes to a LED Volt meter, middle PSU  2 X Dewheaters 11" in length no voltage reduction they get warm,as one sits on top of the other, corrector plate is always clear, the right hand PSU runs a short dew shiel for the guidescope, will in the fulness od time run a GoTo Dob and anything else that may turn up......

[jamie56]

Hi terry ,

Have a look out for a 110ah gel type, should last a fair time before total discharge and added safety of none spill if knocked over, nothing worse than battery acid over everthing, hope this helps.happy gazin and clear skies.

Jamie

[mitchelln]

This is the best advice I've seen for lithium batteries:

http://www.engrish.com/wp-content/uploads//2014/04/prevent_occurrence_bang.jpg

[Mr TamiyaCowboy]

I run lipos myself. 

11.1v 35-70c discharge @2200mah 

top dollar cell packs for fpv flying, they dont mind high drain so long as your sticking to the rated C discharge rate.

problem is if you drain them to much they become highly unstable, overcharge them slightly and they become highly unstable.

with propper care and saftey systems in place they can be good, light weight and packing a huge punch.

my packs i can draw near on 180amps before they blow/explode/catch fire for around 10s. 

a telescope will not put much stain on the cells themselves, but a mistake like reverse polarity

or no low voltage cut off could end up you burning down the whole rig setup..

truth is i use them, have seen them pop and even now dont trust them one bit.

all my batterys are stored in vented metal biscuit tins filled with inert sand.

and checked every two weeks for natural seepage and re-toping to storage voltage levels.

More hassle than the good old lead acid i now use for main 12v power systems.