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Alexborek
06-11-2017, 06:18 PM
So... I'm looking foward to take my setup under some decent dark skies and not rely on leaving the car on for a few hours to power all the equipment. Thus, a neat portable power supply is needed!
Equipment: Laptop, neq6, dew control.
Budget: :shrug:
Aim: to make it through the night!

Cheers!;)

Wavytone
06-11-2017, 06:27 PM
12V inverter to power laptop,
SLA battery + charger from www.batteryworld.com.au
Female car cigarette lighter sockets, inline fuse, wiring and assorted crimp lugs also available.

Or buy the parts from Jaycar and build a DIY power distribution board.

Work out what the peak power draw of your mount, inverter and heaters amount to; the battery must be able to supply that as a peak current.

The second question is how many amp-hours are needed overall (ie on average) (amps x hours, understand ?). This is less than the peak current but I'd multiply by 8 to 12h to make sure it has plenty of capacity.

toc
06-11-2017, 11:37 PM
Quite a fan of these products:

https://powerwerx.com/powerpole-power-distribution

To replace cigarette plugs, but jaycar sell a four way cig adapter that works well and is not expensive.

AEAJR
07-11-2017, 09:25 AM
12V to 110 V are quite inefficient. You are converting 12V to house voltage and then typically the laptop adapter is coverthign back to 19V which is what many of the laptop adapters provide to the computer. Better to go from 12V DC to 19V DC directly using a car adapter for your laptop.

These Lithium Jumper packs can be a good choice. They pack a lot of capacity into a small package
https://www.amazon.com/s/ref=nb_sb_ss_i_3_12?url=search-alias%3Daps&field-keywords=lithium+jump+starter+and+p ortable+power+bank&sprefix=Lithium+jump%2Caps%2C129&crid=2TZRNN12M6VZ3

These can handle high amperage bursts to start cars but the load we put on them is very low and steady. The number you want to look at is the mAH ratngs. This is a capacity number. The higher the mAH rating or AH rating the more capacity the pack has to run your equipment.

I am in the USA so I am showing USA sources. Naturally you will look for local sources.

As far as power distribution well that depends on what kind of power you need and what kind of connectors they use. If they have USB connectors you can plug them into the laptop USB ports. Or many of the car jumpers have USB ports. Some of these can output 19V directly and may be able to power your laptop directly if you have the right kind of cable?


Likewise if you have the larger 12V accesory plug then you can get multiport adapters for those.

xelasnave
07-11-2017, 01:23 PM
Try and figure what you draw.
Starting point perhaps...lap top 2 amps? eq6 say 1 amp, dew control I guess maybe 2 amp...on that basis add them up we get 5 amps..lets say 6 times hours run max probably 8 ..round it out say 50 amps ..at 25 % discharge a 200 amp hour battery would seem the go... but finally you need to know what each item draws to make a list. In any event make sure you have some device that cuts the battery off when it drops to a particular level... from Jcar for under $50.

I like to have a battery bank not struggling and try to discharge only 20% to hopefully extend the battery life.

alex

Littlegreenmen
08-11-2017, 06:10 PM
I've been using a 7ah SLA for about 6 months now without a problem for GoTo as others have stated "keep it charged" and if your using GoTo yourself save a ton of power and make the big alt az moves manually if possible.