Which is best outdoor power source ?

[Nova2000]

Hi all

Normally when we go outdoors we rent a car battery and use clip which are connected to a cigarette lighter splitter which then powers laptop , camera and mount .

But I've heard that these batteries are not safe and they don't give a constant voltage .

What would you'll recommend to power the equipment? We stay up full night cause we don't go often the the dark areas .

Thank you

[Skipper Billy]

'Starter' batteries and 'Leisure' batteries look similar to each other which is a shame as they are completely different animals.

'Starter' batteries are designed to give out an enormous amount of power very quickly to start the car and then be immediately recharged.

'Leisure' batteries are designed to give out low power for a long time and not necessarily;y be recharged straight away - they will also tolerate being deeply discharged although it is best to avoid it.

The best one to use to power your outfit is a leisure battery ie one designed for domestic supplies on a boat or caravan etc.

If you cant access a leisure battery then using a starter battery will do no harm to your equipment.

Both supply ~12v

Hope that helps.

 

[Neil H]

get a good power pack like this it will power everything

https://www.firstlightoptics.com/batteries-powerpacks/celestron-lithium-lifepo4-powertank-pro.html

[Alan64]

Try to find a 12V marine-type battery, and get a box for it.  You can add USB-ports to the box, and other 12V DC connections.  You will need to research that...

https://stargazerslounge.com/topic/288564-portable-12v-power-box/

 

[JonCarleton]

I like the marine battery approach, but I run everything off 110V AC at home, so I just add a 1000W inverter to the mix.  This lets me run off a marine battery for long-term and my truck battery for shorter term.  There is very little loss running this way over running straight 12V from a battery and you get the added advantage of running 5V or other "wall wart transformer" voltages and making use of the voltage control and surge protection in those devices which protect your motors and GOTO computers.

[Swgogtrs]

I had a car battery I used at one time, made the whole case for it, cig outlets, fuses etc. etc. but that puppy was heavy. Thought of using a marine battery, not cheap and you have to remember to charge em all of the time or it can die. 

Finally went to a Celestron power tank. *(you'll love this). After not charging it on a regular basis it died too. Replaced the battery in it and it is up and working now. You can buy replacement battery for it, please make sure you research the brand your getting if not an original. I went cheap ($40) at first and the first one showed up damaged, and the second one did too. Got my money back and purchased locally a Duracell battery at $75.00 (USD). 

Now I leave the radio on it on while working on different things, or leave the radio on for the fur kids while at work. I charge it on a more regular schedule now and no problems for 8 months now. 

[bsdsgl84]

On 16/02/2020 at 04:16, Nova2000 said:

Hi all

Normally when we go outdoors we rent a car battery and use clip which are connected to a cigarette lighter splitter which then powers laptop , camera and mount .

But I've heard that these batteries are not safe and they don't give a constant voltage .

What would you'll recommend to power the equipment? We stay up full night cause we don't go often the the dark areas .

Thank you

Hello, 

Good to hear from you.., 

To be honest, it depends on a number of factors: - 

• Mount  
• Ambient temperature 
• Actual activity requirements
• Peripheral and accessory power draw profile 

to name a few.., 

Not a lot of folks think about how "noisy" (frequent, random individual polling for more power) dew heaters are as far as power draw is concerned and the fact that if on a shared power source, it can affect the operation of other devices also powered from the same power source. 

A common mistake folks make when faced with lots of deviices to power is to go out and get a bigger, single battery, when really is far more effective to simply use more power sources, be they batteries or AC power. Ideally, you'd want dew controllers, variable-draw devices (like computers)  fan-assisted and other similarly "noisy" devices being powered by sources that are independent from your mount for one - and cameras. 

For higher-end mounts 12v from a deep cycle battery is actually not ideal in conditions where the load is high (examples of these include Losmandy, Astro-Phyics and Paramount) and / or in cold weather.  I've owned both Losmandy and currently have an AP mount, and both these mounts are much happier at 15 VDC under load or in colder temperatures.., this is based on information provided by both AP and Losmandy themselves over the years..,  

Best to assess and categorize your devices into noisy vs not-noisy and calculate their power draws and use separate power sources for groups of devices. Bit more work in terms of set up, but safer and more effective in the long run. 

Hope that helps.., 

Best.., 

bsdsgl84 

 

 

 

 

[Nova2000]

9 hours ago, Swgogtrs said:

I had a car battery I used at one time, made the whole case for it, cig outlets, fuses etc. etc. but that puppy was heavy. Thought of using a marine battery, not cheap and you have to remember to charge em all of the time or it can die. 

Finally went to a Celestron power tank. *(you'll love this). After not charging it on a regular basis it died too. Replaced the battery in it and it is up and working now. You can buy replacement battery for it, please make sure you research the brand your getting if not an original. I went cheap ($40) at first and the first one showed up damaged, and the second one did too. Got my money back and purchased locally a Duracell battery at $75.00 (USD). 

Now I leave the radio on it on while working on different things, or leave the radio on for the fur kids while at work. I charge it on a more regular schedule now and no problems for 8 months now. 

Hi 

How long does it power your gear ?

[Swgogtrs]

1 hour ago, Nova2000 said:

Hi 

How long does it power your gear ?

I do most of my observing from my back yard at the moment. I have gotten a good 7 hours out of it, but consider this, I am not out all night either. It is a Celestron power tank 17. I am only powering the scope though, I don't have extras connected to it, like a designated astro camera$, auto guider$ and a lap top etc. Hopefully soon.   

[noah4x4]

On 18/02/2020 at 19:13, JonCarleton said:

I like the marine battery approach, but I run everything off 110V AC at home, so I just add a 1000W inverter to the mix.  This lets me run off a marine battery for long-term and my truck battery for shorter term.  There is very little loss running this way over running straight 12V from a battery and you get the added advantage of running 5V or other "wall wart transformer" voltages and making use of the voltage control and surge protection in those devices which protect your motors and GOTO computers.

Good solution!

For astronomy I use (UK) 240v/12v AC/DC as I never leave home. But when I did, I used a 12v 22Ah Tracer Li-Po for camera, focuser etc and 20v MaxOak K2 for Intel NUC. If I had my time again, I would pursue an Inverter solution (much cheaper!).

For example ; I am also involved with outdoor sports broadcasting away from any mains supply. There I use a 12v 18Ah mobility scooter battery. I then use a Bestek 12v/240v 300 watt inverter from that to offer me the equivalent of local mains power. I can then use regular AC/DC (or POE)  'bricks' to distribute power at the 24v, 18v and 12v I need for different devices. It might be wise to get a 400 watt or even higher wattage Inverter for astronomy, but that depends on the demands of your kit.

[Nova2000]

How to calculate how long can a battery power a mount ? I don't know much about this .

[noah4x4]

If your telescope requires 12 volts (force) and draws 2 Amps (current), a quality 12v  battery rated 12 volts 8 Amp Hours (Ah = capacity ) will supply power for four hours (8 Ah/2 amps = 4 hours) assuming it can supply continuous current exceeding 2 amps.

Beware, some cheap asian  manufactured batteries  claim large capacity amp hours (Ah) but offer low continuous current. If the continuous current offered exceeds that drawn by the device it will only take what it needs. However, if the continuous current is too low there could be problems resulting in damage. Similarly if too few or too many volts. 

Power might be expressed in watts. Watts = amps x volts. Hence if a scope was rated 24 watts and 12 volts it needs 2 amps. I mention this as most AC/DC bricks supplied with telescopes are rated in Volts and Watts and you might need to convert the current required to amps. 24 watts/12 volts means it needs 2 amps. A 10 Amp hour battery offering 2 amps would then last five hours. Again beware, cheap batteries have discharge curves that overstate their capabilities. 12 volts might rapidly deplete to perhaps 9.6v.

Edited February 26, 2020 by noah4x4

[Nova2000]

https://www.tracerpower.com/12v-22ah-lithium-polymer-battery-pack.html

Are battery packs of this type usefull?

Does anyone have a link to a battery pack building guide  ?

thank you 

 

Edited March 1, 2020 by Nova2000

[johninderby]

The LifeP04 batteries are the ones to go for. Nott just better suited to powering a mount due to their discharge characteristics but much safer. 

https://www.tracerpower.com/tracer-lifepo4-battery-packs-high-output-current.html

Edited March 1, 2020 by johninderby

[Juicy6]

On 22/02/2020 at 23:14, bsdsgl84 said:

Not a lot of folks think about how "noisy" (frequent, random individual polling for more power) dew heaters are as far as power draw is concerned and the fact that if on a shared power source, it can affect the operation of other devices also powered from the same power source. 

Poorly RFI shielded PWM heater controllers emit noise. IMHO controllers are also superfluous. I leave my dew heater on full power all the time. It draws only 0.6 ampere for 7 watts. Its resistive load will give absolutely no noise.

[PlanetGazer]

On 16/02/2020 at 16:58, Neil H said:

get a good power pack like this it will power everything

https://www.firstlightoptics.com/batteries-powerpacks/celestron-lithium-lifepo4-powertank-pro.html

I second that

[Nova2000]

If I get a 60ah. Leisure or marine battery. I logically be able to power the mount , laptop and dew heaters/camera all together then I suppose?

(Correct me if I'm wrong my knowledge about batteries is very limited)

[m.tweedy]

As stated above the LiPo4 batteries are ideal.

They are also a LOT lighter than lead acid ones. A 24Ah one is virtually equivalent to a 50 Ah lead acid one (leisure batteries can be discharged more that the 50%)

Here is another supplier that I use as well as Tracer. Same technology different brand.

https://www.libertybatteries.com/lithium-golf-trolley-battery-package-36-hole-extended-life-97-p.asp

36 hole is a 24Ah one.

Edited March 19, 2020 by m.tweedy
additional info

[Nova2000]

Those lifepo4 battery packs come with a cigarette lighter port so ,I should be able to use a splitter and power multiple stuff. 

You mean a lifepo4 can power gear for longer when you say 24ah=59ah of  lead acid ?

[m.tweedy]

3 minutes ago, Nova2000 said:

Those lifepo4 battery packs come with a cigarette lighter port so ,I should be able to use a splitter and power multiple stuff. 

You mean a lifepo4 can power gear for longer when you say 24ah=59ah of  lead acid ?

Lead acid batteries should not normally be discharged more than 50% otherwise damage can occur. Leisure ones can be discharged more-not sure by how much more.

24ah LiPo ones have a flat discharge ie output virtually the same level of power until empty.

[m.tweedy]

I B also moved away from cigarette type power to Anderson Powerpole. I much more secure connection.