Power Tanks, batteries and other wizardry...

[Newforestgimp]

Evening All,

what suggestions for outdoor power source for mount etc ?

I am an electrickery phobic have no real understanding of which sockets are required and the off the shelf power tanks are probably the answer but they seem very expensive for the convenience factor ? are there other better options than the Astro specific  power tanks ?

Andy

[nephilim]

6 minutes ago, Newforestgimp said:

Evening All,

what suggestions for outdoor power source for mount etc ?

I am an electrickery phobic have no real understanding of which sockets are required and the off the shelf power tanks are probably the answer but they seem very expensive for the convenience factor ? are there other better options than the Astro specific  power tanks ?

Andy

I use this & it will keep my imaging rig going for an evenings AP, its not cheap but, lightweight compared to a lead battery & doesnt need to be 'looked after' as a lead one does. https://www.firstlightoptics.com/batteries-powerpacks/celestron-lithium-lifepo4-powertank-pro.html

[teoria_del_big_bang]

What equipment are you needing to power and is this for use in remote areas or from your back garden ?

Steve

[Newforestgimp]

Yeah the price is prohibitive TBH, £250 seems like a lot to me.

[Newforestgimp]

Just now, teoria_del_big_bang said:

What equipment are you needing to power and is this for use in remote areas or from your back garden ?

Steve

I think it will be mount, dew heater, laptop, phone.

Home and remote is what I envisage ?

[Alien 13]

The power requirements depend on the specific mount etc. for example my EQ3 only requires 6V so I can power it, my dew heaters and tablets/mobiles etc of cheap mobile phone power banks making everything very portable.

Alan

[nephilim]

8 minutes ago, Newforestgimp said:

Yeah the price is prohibitive TBH, £250 seems like a lot to me.

I agree with you there. It was actually £39 cheaper when I bought it 2 months ago (I've noticed a fair few pieces of astro related gear has recently shot up in price for no apparent reason) but still pricey. I wanted something that was relatively light, reliable for a full evening session & easy to use which this is. A lead battery although cheaper needs to be charged up every couple of months & cant be run down down where as this can & when not in use can just be put away & forgotten about.

[SMF]

Hi Andy,

Been looking into this as well.

Lowest cost option I’ve seen so far is:

https://www.halfords.com/motoring/battery-maintenance/jump-starters/4-in-1-jump-starter-594335.html
 

Machine Mart do a few alternatives as well:

https://www.machinemart.co.uk/c/clarke-jump-starts/
 

Then this on Amazon:

https://www.amazon.co.uk/BEAUDENS-Portable-Generator-Phosphate-Emergency/dp/B07MC7TV2G/ref=sr_1_9?dchild=1&keywords=portable+power+bank+12v&qid=1608416316&sr=8-9
 

Not made my mind up yet, convenience of Lithium or low cost of sealed lead battery.
 

Hope helps.

Steve

[Newforestgimp]

3 minutes ago, Alien 13 said:

The power requirements depend on the specific mount etc. for example my EQ3 only requires 6V so I can power it, my dew heaters and tablets/mobiles etc of cheap mobile phone power banks making everything very portable.

Alan

Interesting,

as I say I’m electric phobic it’s a dark art to me, I have a EQM-35, will need to run a dew heater and phone/tablet nonguiding with laptop for now.

[Ships and Stars]

Hi there, I went to Tayna Batteries UK and just bought a van leisure battery. 

They have the Exide 80 amp hour for £62 plus £8 shipping. That's a LOT of reserve power.

With 80 amp hour, you can power everything you want for the whole night and then some, or just run the scope for at least 3 or 4 nights. I can even run a diesel heater and a 150W stereo most of the night off of mine.

The drawback? Big and heavy compared to a li ion pack but not too bad. 27 x 22 x 17cm. A real workhorse and probably half the price of tiny 7 amp hour lithium ion pack. 

If you go that route, you'll need a decent 12v car battery charger as well. I'd just get one from screwfix, etc.

Edited December 19, 2020 by Ships and Stars

[Newforestgimp]

5 minutes ago, SMF said:

Hi Andy,

Been looking into this as well.

Lowest cost option I’ve seen so far is:

https://www.halfords.com/motoring/battery-maintenance/jump-starters/4-in-1-jump-starter-594335.html
 

Machine Mart do a few alternatives as well:

https://www.machinemart.co.uk/c/clarke-jump-starts/
 

Then this on Amazon:

https://www.amazon.co.uk/BEAUDENS-Portable-Generator-Phosphate-Emergency/dp/B07MC7TV2G/ref=sr_1_9?dchild=1&keywords=portable+power+bank+12v&qid=1608416316&sr=8-9
 

Not made my mind up yet, convenience of Lithium or low cost of sealed lead battery.
 

Hope helps.

Steve

This is more like it, repurposing something not branded as Astro and pushing price up 👍

many clues on how long a charge will last ?

[Alien 13]

4 minutes ago, Newforestgimp said:

Interesting,

as I say I’m electric phobic it’s a dark art to me, I have a EQM-35, will need to run a dew heater and phone/tablet nonguiding with laptop for now.

Think that mount needs 12V so my solution wont work.

Alan

[Newforestgimp]

2 minutes ago, Ships and Stars said:

Hi there, I went to Tayna Batteries UK and just bought a van leisure battery. 

They have the Exide 80 amp hour for £62 plus £8 shipping. That's a LOT of reserve power.

With 80 amp hour, you can power everything you want for the whole night and then some, or just run the scope for at least 3 or 4 nights. I can even run a diesel heater and a 150W stereo most of the night off of mine.

The drawback? Big and heavy compared to a li ion pack but not too bad. 27 x 22 x 17cm. A real workhorse and probably half the price of tiny 7 amp hour lithium ion pack. 

If you go that route, you'll need a decent 12v car battery charger as well. I'd just get one from screwfix, etc.

Thank you,

how do you go about the physical connections from the devices to the battery ? 
sorry if this sounds a but dumb but unless there’s a socket on a box I get confused how to DIY it ?

[Bartman]

This is what I use. A little expensive but lightweight, long lasting and lots of connections. Worth the money for me. 
 

https://www.skyatnightmagazine.com/reviews/accessories/bresser-portable-power-supply-100-watt-review/

[Ships and Stars]

17 minutes ago, Newforestgimp said:

Thank you,

how do you go about the physical connections from the devices to the battery ? 
sorry if this sounds a but dumb but unless there’s a socket on a box I get confused how to DIY it ?

I just use a fused cigarette lighter socket that has battery alligator clamps on the ends of my cables - those just clamp directly on to the +/- battery posts. I'll stick a small plastic storage tub over the top to keep the dew off, or whatever's handy. You can get a two ciggie socket cable and run a dual USB adapter off one, and plug the dew heater into the other. The dew heater controller should have a power out port for the telescope.

Each person's set-up is a little different, so you will have to look online for the right parts.

I also have a charger for my laptop that plugs into a cigarette lighter.  

Beware of cheap three socket cigarette lighter adapters, the wiring is really small gauge for the load it has to carry. You want a good quality cable and socket (s) that's long enough to do the job. 

Maybe draw a simple diagram of everything you need to run, then see how many cig sockets/power ports you need and at what voltage. The laptop charger would be a separate item to buy if you don't have one. 

It all makes sense once you do a bit of searching online for the right bits!

If others have a simpler solution, then naturally that's perhaps more attractive, but mine's not terribly complicated. I do visual only, but I'm sure I could easily run an astrophotography setup off mine in remote areas.

Edited December 19, 2020 by Ships and Stars

[Jiggy 67]

37 minutes ago, Newforestgimp said:

Yeah the price is prohibitive TBH, £250 seems like a lot to me.

Yep, it’s expensive but most things of quality in astronomy are. If you want a power supply that does the job year in year out without losing it’s ability like lead batteries do and is simple to use with multiple devices then this is worth the money and will make life easy. You could go for cheaper options but life could be difficult and require a bit of electrical knowledge. I have the same knowledge as you so I have the Celestron battery and it works perfectly powering an EQ6 R Pro and dew bands over at least two or three nights without a recharge 

[Newforestgimp]

17 minutes ago, Bartman said:

This is what I use. A little expensive but lightweight, long lasting and lots of connections. Worth the money for me. 
 

https://www.skyatnightmagazine.com/reviews/accessories/bresser-portable-power-supply-100-watt-review/

Thanks 🙏🏼. Another promising off the shelf 

[Ships and Stars]

Lead acid batteries will last for years if you don't let them sit for months and go flat. When a lead acid battery drops below around 12.4 volts, sulfation begins to occur which coats the plates inside the battery with fine deposits and prevents the battery from taking or keeping a proper charge. The solution is to put it on a trickle charger or charge it occasionally. 

They are more maintenance than li ion, but everything has a shelf life and if the battery does pack it in, it's a lot cheaper to replace as all the wiring and sockets is independent of the battery as opposed to a li ion pack where it's all integrated.

Anyway, that's my sales pitch!  

PS I do like to mess about with things and am fairly good with making stuff and I am CHEAP, lol, so if you want no fuss/simple then perhaps li ion is the ticket. A lot lighter as well. 

Edited December 19, 2020 by Ships and Stars

[SMF]

33 minutes ago, Ships and Stars said:

Hi there, I went to Tayna Batteries UK and just bought a van leisure battery. 

They have the Exide 80 amp hour for £62 plus £8 shipping. That's a LOT of reserve power.

With 80 amp hour, you can power everything you want for the whole night and then some, or just run the scope for at least 3 or 4 nights. I can even run a diesel heater and a 150W stereo most of the night off of mine.

The drawback? Big and heavy compared to a li ion pack but not too bad. 27 x 22 x 17cm. A real workhorse and probably half the price of tiny 7 amp hour lithium ion pack. 

If you go that route, you'll need a decent 12v car battery charger as well. I'd just get one from screwfix, etc.

I like Ships and Stars suggestion. Nice one.

Ive just looked at the web site and noticed this to go with the battery:

https://www.tayna.co.uk/battery-leads-terminals/battery-boxes/bison-box/
 

Starts to add up but for 80 amp hours of power in a sealed box that’s cheap and leisure batteries only need a top up charge every 2 or 3 months if not used regularly. 

[nephilim]

1 hour ago, SMF said:

Hi Andy,

Been looking into this as well.

Lowest cost option I’ve seen so far is:

https://www.halfords.com/motoring/battery-maintenance/jump-starters/4-in-1-jump-starter-594335.html
 

Machine Mart do a few alternatives as well:

https://www.machinemart.co.uk/c/clarke-jump-starts/
 

Then this on Amazon:

https://www.amazon.co.uk/BEAUDENS-Portable-Generator-Phosphate-Emergency/dp/B07MC7TV2G/ref=sr_1_9?dchild=1&keywords=portable+power+bank+12v&qid=1608416316&sr=8-9
 

Not made my mind up yet, convenience of Lithium or low cost of sealed lead battery.
 

Hope helps.

Steve

I'd had a look at the Halfords one & a few of the jump start type batteries before just taking the hit for the Celestron one, but the whole thing of not been able to run them right down (meaning yet another thing to keep an eye on) & remembering to charge every couple of months if not in use put me off, plus most of these don't have USB 3 (only USB 2.0) which a lot of astro related gear benifits from. 

I'll also add that although not a deal breaker, there's a big red (there's also white) light that's on the side & is a massive help as it illuminates your whole imaging area rather than a head torch or handheld torch, great for setting up & working with. I obviously wouldn't be shelling out this type of cash just for the big red light though 😂

Edited December 20, 2020 by nephilim

[Newforestgimp]

11 hours ago, Bartman said:

This is what I use. A little expensive but lightweight, long lasting and lots of connections. Worth the money for me. 
 

https://www.skyatnightmagazine.com/reviews/accessories/bresser-portable-power-supply-100-watt-review/

Thanks 🙏🏼. Another promising off the shelf 

[Newforestgimp]

Anybody know how suitable this might be ?

https://www.maplin.co.uk/portable-power-technology-powerpack-100-0616010988476?wgu=276885_59032_16084570983641_95583ad322&wgexpiry=1616233098&utm_source=webgains&utm_medium=affiliate&utm_campaign=59032
 

it seems like the specs are deliberately confusing, some quote AHours sone Mha this one WattHours ??

wished I’d listened at college now...

Andy

[Shimrod]

12 hours ago, nephilim said:

I use this & it will keep my imaging rig going for an evenings AP, its not cheap but, lightweight compared to a lead battery & doesnt need to be 'looked after' as a lead one does. https://www.firstlightoptics.com/batteries-powerpacks/celestron-lithium-lifepo4-powertank-pro.html

I have one of these as well (it can be picked up for £214 from picstop) and it is both lightweight and has all the power connectors I need. You don't have to worry about keeping it charged (like lead acid or Li-on) batteries, and the battery technology (LiFe-Po) is much safer than Li-on when it comes to possibly knocks or damage to the battery. It beats lugging the equivalent 20kg lead acid battery around and it will last for years. It is the battery technology rather than the brand that makes this expensive - have a look at tracer batteries which use the same technology and cost similar amounts.

[teoria_del_big_bang]

Some interesting finds and I am also particular interested how good either the Amazon one or the Maplin one is (I guess Mapling have remained an on line company as sadly I thought they went bust a while ago)

Amazon

Maplin

Both claim to be about 150W/Hrs which for a smallish imaging rig sounds good. One thing I would say is that whatever power they claim they can deliver in practice it will always will be less and in some cases maybe only half (that is a guess I cannot say for sure and sometimes you only find these things out by trying them). Many things contribute to lack of performance such as temperature, efficiency of the circuitry when creating all the different voltages.

If it was just a HEq5 size mount and a dew band drawing an average total of 1 to 2 amps at 12V throughout the night that is an average of 24 Watts so in theory would last 150 / 24 = 6.25 hours. But I would think if I were buying this I would only bargain on getting 4 to 5 hours. 

Now it may well be you actually only draw around 1A on average with this setup so long as you are not slewing from target to target every few minutes as it is the fast slewing to target that draws a high current (on HEQ5 I think it states around 2A). When tracking it will only be drawing about 0.5 A.
A dew band probably takes 0.5 to 1A depending on size, so a 100 mm dia scope probably about 0.5A but a bigger one on 200mm or bigger diameter may be 1A or a little more.
That's why I suggested maybe 2A average. But if a small scope and you are not doing a lot of slewing you may keep to around 1A to 1.5A so may get 8 hours or more, very difficult to say without knowing  exactly the current draw of each item and the efficiency of the supply.

One thing I haven't mentioned is the laptop. If use on an inverter then this will very quickly run down your battery and no actually idea how long it will last with the laptop as well. In fact it is impossible because many older laptops have woefully poor battery life so would be on mains power nearly all night. Most laptops have power supplies around 50 to 80W (I think - mine is 65W at 20V). This will be a maximum it can provide and so the laptop may not take this amount to charge or run. But lets say it takes 40W at 20V that means that with 150W/Hrs available (if it were 100% efficient - which it will not be) then the laptop alone will only run for 3.75 hrs (150 / 40).
Also the inverter will be nowhere near 100% efficient and my guess is in reality you will get only 2 to 2.5 hours running the laptop + of course what ever the battery can provide. 

So as I said very difficult without all the info of power used by each item and also how efficient the supply is with a small mount, small dew band and laptop with good battery my best  guess is you might get 2 to 3 hours from these at best.

There are things you can do to extend this life all of which are to draw less current:

• Use dew band at a lower voltage than 12V so it does its job but not over warm the scope.
• Use a low power tablet instead of laptop.
• If you use laptop then get a good battery, maybe two and hot swap them when one runs low (I do not know how feasable this is as I have never tried) but even one good battery means you can run only on battery for 2 to 3 hours before plugging into invertor.
• Do not use the invertor to run laptop but get a seperate 12V to Laptop Voltage supply (Like This) that will probably be more efficient and run it from the 12V, also only plug into supply for a short while and run most of night from battery (or ideally batteries).
• Dim screen right down and let it automatically turn off altogether when not being used.
• Install  a solid state drive rather than conventional HDD.

On a last note I think the Watt/Hrs is a better indicator of battery life than A/Hrs or mA/Hrs.
mA/Hrs is really the same as A/Hrs but rated in 1/1000's of an Amp rather than Amps. So if you divide mA/Hrs by 1000 you get A/Hrs.
If it is stated in A/Hrs or mA/Hrs then really it should state at what voltage. Some scrupulous sellers quote the A/Hrs as a ridiculous figure that makes it seem really powerful but they are quoting it from what is on the batteries which will be 3.6V for lithium-ion. But at 12V the figure will be 3.33 less than this quoted figure.

Steve

Edited December 20, 2020 by teoria_del_big_bang

[Cosmic Geoff]

If you are electro-phobic and do not want to pay for a LiFePo power tank, a car engine starter would be best buy.  You can get splitters to power items other than the mount.  A laptop would be a power hog, but I rely on the internal battery of mine, even though the endurance is very short.  I don't use dew heaters, as I have only rarely experienced the need with a dew shield in place.   Dew intensity may vary from one part of the country to another.