Is this suitable?

[Jm1973]

Hi people. I'm here to pick your brains again. 

Would you think this is a suitable power supply to power my mount and camera in the field?

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

It's got 2 cigarette lights type 12V ports, and a USB. It's 17ah.

I only have to power my camera and EQ5 synscan. I would think it should be plenty. 

And it's £50 quid as opposed to about £130 for the Skywatcher 17ah version...

Opinions, thoughts, alternatives are all very welcome.

Edited November 27, 2020 by Jm1973

[Peter Drew]

Should be ok, the astro branded ones are usually more expensive     🙂

[Waldemar]

The powersupply you linked to, is a jumpstarter, meant to provide a very high Amps output for a very short time to start cars...
What you need is a battery that can deliver a low Amp output for a long time. A totally different kind of battery, called deep cycle battery.
The best would be a LiFePO4 battery, which can deliver constant power until it is almost empty, while the lead-acid batteries you are mentioning drop below 12 Volts very fast and make your equipment not doing the things you want it to do.
The difference in price is not because it can be used for astro purposes, but because it is a totally different type of battery, with a far better output and also far longer lifespan.

Be aware that the so called cigarette lighter connectors are exactly that: to light cigarettes, not for constant power use. 
The plus connectors (tip) of the plugs are spring loaded and tend to work themselves out of the ports to make a bad or non contact when you least expect it.
I really don't understand why astro companies still use those 🤬 things for such expensive equipment. Must be economics...
Just use connectors that are made for the purpose of constant full contact.

Edited November 27, 2020 by Waldemar

[Jm1973]

27 minutes ago, Waldemar said:

The powersupply you linked to, is a jumpstarter, meant to provide a very high Amps output for a very short time to start cars...
What you need is a battery that can deliver a low Amp output for a long time. A totally different kind of battery, called deep cycle battery.
The best would be a LiFePO4 battery, which can deliver constant power until it is almost empty, while the lead-acid batteries you are mentioning drop below 12 Volts very fast and make your equipment not doing the things you want it to do.
The difference in price is not because it can be used for astro purposes, but because it is a totally different type of battery, with a far better output and also far longer lifespan.

Be aware that the so called cigarette lighter connectors are exactly that: to light cigarettes, not for constant power use. 
The plus connectors (tip) of the plugs are spring loaded and tend to work themselves out of the ports to make a bad or non contact when you least expect it.
I really don't understand why astro companies still use those 🤬 things for such expensive equipment. Must be economics...
Just use connectors that are made for the purpose of constant full contact.

Two answers, both completely different.

I know a lot of people use these types of multi-functional jump-starters to power their mounts. It was more of a question as to whether this particular one is ok, not so much whether jump-starters can be used.

Interesting that you should say not to use them at all.

[LoveFromGallifrey]

30 minutes ago, Jm1973 said:

Two answers, both completely different.

I know a lot of people use these types of multi-functional jump-starters to power their mounts. It was more of a question as to whether this particular one is ok, not so much whether jump-starters can be used.

Interesting that you should say not to use them at all.

I don't use it to power a mount currently, but I have that and use it to power 3 dew heaters for via a controller for several hours without any issues. The power cable uses a cigarette plug. 

Brought it for three reasons - 1. because it was cheaper than a branded powerpack for astronomy and 2. Because other people recommended it as an alternative, and 3. after some issues with my car's battery I decided I needed this sucker handy. 

Edited November 27, 2020 by LoveFromGallifrey

[teoria_del_big_bang]

Personally, I would sort of agree with both replies, which may sound odd as they are quite different.

In short:

• I suspect the jumpstarter will in effect be no real different to the skywatcher lead acid option.
• From my experience with them they will power a small mount and camera for a reasonable time , probably for at least 4 to 6 hours reliably - but all depends on whether it is just the mount and camera and how often you are slewing at fast rate which takes a lot more current, and that you are not also using dew bands and other bits on the 12V.
• I suspect it will last a number of years so long as you maintain its charge and when you have finished a session you put it on trickle charge till fully charged and when left in storage you take it out and trickle chage to fully charged every few weeks. But that will be no different with the Skywatcher version.
• A far better, but more expensive, option is something like Celestron Power Tank

Inside the starter will be a small lead acid battery similar to 17AH Battery and in my opinion is fine for powering a mount and I have used similar in the past with no issues.

I cannot tell for sure , without buying one and looking inside, but as it is a relatively cheap so called "Jump Starter" if it like the ones from Halfords I have had in the past it will not have a specialized high current battery inside but one very like the link which are still capable of high currents so will start most car engines if it is fully charged but do not tend to last too long if used a lot. But they seem to work fine as well delivering 1 to 2 A as you will require, so long as they are looked after properly and charged properly. 

To be honest although again I do not know I always assumed the Skywatcher Power Tanks  (which are now £99 from FLO Skywatcher Power Tank 17aH ) were just the same as the Jump Starters and would have the same batteries. But I could be wrong and would be nice to know from any owners that have had them apart if the batteries inside are any different.

BUT, as @Waldemar does say it is not ideal for several reasons .

Whatever, both the Jumpstarter and the Skywatcher are lead acid and do suffer from lowering in voltage as they discharge and will start off at 13.8 V  and will quickly drop to around 12 to 12.5 v and eventually will be a little below 12V as they approach being discharged. Again when I used these I never had issues either with mount or camera when even a little below 12V but I have read threads where people do have issues with the mount when slewing at 12v or below.

Also they need looking after in that they do not like being fully discharged and if left discharged for any length of time you will lose a lot of its potential and will not really be capable of providing 17AH anymore and if left a long while will become almost useless. They will also discharge themselves to some extent even when left in storage not being used so if you need to use it and have not used it for a month or so you may need to do a bit of a charge before using it if you want it's full potential.

A far better option is a  LiFePO4 battery, but you will pay more than £50  for something around 17Ah, but ultimately might save money as they will last many years longer and will be easier to look after (and they are a lot lighter if you are traveling with them.

Also I do agree with @Waldemar about the cigarette lighter connectors, totally useless and give too many problems with bad connections for astro use but so much equipment uses them.

 

Where are you wanting to use your scope ? Is it just from home or are you traveling to remote sites ?

If just from home why not use something like this Outdoor 12V supply Ideally housed in a waterproof housing that is large enough to stop supply over heating and also then connected via a Rcd unit.

Steve

Edited November 27, 2020 by teoria_del_big_bang

[Jm1973]

16 minutes ago, teoria_del_big_bang said:

Personally, I would sort of agree with both replies, which may sound odd as they are quite different.

In short:

• I suspect the jumpstarter will in effect be no real different to the skywatcher lead acid option.
• From my experience with them they will power a small mount and camera for a reasonable time , probably for at least 4 to 6 hours reliably - but all depends on whether it is just the mount and camera and how often you are slewing at fast rate which takes a lot more current, and that you are not also using dew bands and other bits on the 12V.
• I suspect it will last a number of years so long as you maintain its charge and when you have finished a session you put it on trickle charge till fully charged and when left in storage you take it out and trickle chage to fully charged every few weeks. But that will be no different with the Skywatcher version.
• A far better, but more expensive, option is something like Celestron Power Tank

Inside the starter will be a small lead acid battery similar to 17AH Battery and in my opinion is fine for powering a mount and I have used similar in the past with no issues.

I cannot tell for sure , without buying one and looking inside, but as it is a relatively cheap so called "Jump Starter" if it like the ones from Halfords I have had in the past it will not have a specialized high current battery inside but one very like the link which are still capable of high currents so will start most car engines if it is fully charged but do not tend to last too long if used a lot. But they seem to work fine as well delivering 1 to 2 A as you will require, so long as they are looked after properly and charged properly. 

To be honest although again I do not know I always assumed the Skywatcher Power Tanks  (which are now £99 from FLO Skywatcher Power Tank 17aH ) were just the same as the Jump Starters and would have the same batteries. But I could be wrong and would be nice to know from any owners that have had them apart if the batteries inside are any different.

BUT, as @Waldemar does say it is not ideal for several reasons .

Whatever, both the Jumpstarter and the Skywatcher are lead acid and do suffer from lowering in voltage as they discharge and will start off at 13.8 V  and will quickly drop to around 12 to 12.5 v and eventually will be a little below 12V as they approach being discharged. Again when I used these I never had issues either with mount or camera when even a little below 12V but I have read threads where people do have issues with the mount when slewing at 12v or below.

Also they need looking after in that they do not like being fully discharged and if left discharged for any length of time you will lose a lot of its potential and will not really be capable of providing 17AH anymore and if left a long while will become almost useless. They will also discharge themselves to some extent even when left in storage not being used so if you need to use it and have not used it for a month or so you may need to do a bit of a charge before using it if you want it's full potential.

A far better option is a  LiFePO4 battery, but you will pay more than £50  for something around 17Ah, but ultimately might save money as they will last many years longer and will be easier to look after (and they are a lot lighter if you are traveling with them.

Also I do agree with @Waldemar about the cigarette lighter connectors, totally useless and give too many problems with bad connections for astro use but so much equipment uses them.

 

Where are you wanting to use your scope ? Is it just from home or are you traveling to remote sites ?

If just from home why not use something like this Outdoor 12V supply Ideally housed in a waterproof housing that is large enough to stop supply over heating and also then connected via a Rcd unit.

Steve

Thanks for the replies.

I used to build and fly drones so I am used to the drill with charging/discharging/recharging etc.

I will only be using this when I travel to dark sites etc. Which realistically won't be that often.

I generally image from home, and I use an extension lead in a box, going back to the house and plugged into an RCD then.

 

Edited November 27, 2020 by Jm1973

[teoria_del_big_bang]

Just now, Jm1973 said:

Thanks for the reply.

I used to build and fly drones so I am used to the drill with charging/discharging/recharing etc.

I will only be using this when I travel to dark sites etc. Which realistically won't be that often.

I generally image from home, and I use an extension lead in a box, going back to the house and plugged into an RCD then.

 

Very much like myself then.

If you fly and maintain drones I suspect you would have little issues with buying a 17A/H  battery  and making a nice box with all the required connectors.

Personally, I think it would work fine for the small current you are drawing (probably no more than 1a most of time). If you are using Dew bands though this may add around another 1a to the draw.

In my ey experience I have used them for my mount in the past and also used to use them when overnight carp fishing to run lights and a 12v television so worked on low currents.

Steve

[Jm1973]

17 minutes ago, teoria_del_big_bang said:

Very much like myself then.

If you fly and maintain drones I suspect you would have little issues with buying a 17A/H  battery  and making a nice box with all the required connectors.

Personally, I think it would work fine for the small current you are drawing (probably no more than 1a most of time). If you are using Dew bands though this may add around another 1a to the draw.

In my ey experience I have used them for my mount in the past and also used to use them when overnight carp fishing to run lights and a 12v television so worked on low currents.

Steve

Hi  Steve.

While I currently don't have dew heaters, now that weather is getting colder it may be that I start to need them soon.

I have noticed the telescope gets pretty wet now. Although it hasn't been a problem as far as the optics are concerned.. yet.

Maybe I should just buy a leisure battery and build a box around it like you suggest....

Any thoughts on using that sort of setup?

John.

Edited November 27, 2020 by Jm1973

[teoria_del_big_bang]

John,

That's what I would do. If you do not move too far from the car so weight not a big issue you can either but the 17Ah battery and leave a space to add a second one if you need more power or probably will get a bigger battery for £50 or so.  It/s not easy to say how long things will run reliably run on these batteries as i am sure you know although it states 17Ah you will not get a full 17 hours at 1 amp from them. Also whether your mount will give any funnies at 12v or below really needs checking, my HEQ5 seemed fine at even 11.5v but the manual says not to go below 12v and I have read threads about steppers missing pulses at low voltages.

Steve

[Zermelo]

1 hour ago, Jm1973 said:

Maybe I should just buy a leisure battery and build a box around it like you suggest....

Any thoughts on using that sort of setup?

There have been several threads in the DIY Astronomer thread, for example:

https://stargazerslounge.com/topic/187469-powertank-step-by-step/?tab=comments#comment-1952536

https://stargazerslounge.com/topic/212375-custom-power-pack-with-all-electronics/?tab=comments#comment-2271189

https://stargazerslounge.com/topic/303145-field-power-pack-battery-box/?tab=comments#comment-3316386

Some of these are very ambitious!

[nephilim]

I luckily bought the Celestron 13.2Ah power tank before it recently jumped in price another £30 or so for whatever reason. It should power all my kit for a good 8hrs plus being lithium doesn't need as much looking after. Unfortunately its pretty expensive but then again what in this hobby isn't. Sorry not much help but just adding my two penneth

[StevieDvd]

Can't vouch for that specific jumpstart model but you get essentially the same issue with the astro equivalents in that leaving it to run down can prevent it working. You'l see a lot of them for sale used with comments like just needs a new battery.

I have an old Maplins jump starter where I replaced the battery with a decent branded one and it's served me well for a few years. It even starts cars like the big 4x4 truck of my neighbour. A monthly charge keeps it going but I use a C-Tek charger rather than the cheap wall plug-in.

 

[Waldemar]

In fact your best option is to get soldering skills and knowledge about electric circuits and build your own powerbox, using quality parts.
Simple electrickery is no rocket science 😁

[Cosmic Geoff]

You can use a variety of things to power a mount (see above replies.)

I used a 7 AH sealed lead-acid battery + home-made leads for several years until it seemed to be needing a charge more often.  Now I use a Celestron LiFePo 84.48Wh power tank (which also works as a low-voltage inspection light - very handy).

I also have an engine starter/light/air compressor unit which I acquired used along with a telescope.  It was fine till the mount stared acting up and I found the battery had partly failed.  I wanted to repair it, so had to buy a matching battery (12v 22AH, sealed lead-acid) for £47 (ouch).  It has a trickle charger accessory to keep it charged between uses.

I think that regardless of what engine starter or astro 'power tank' you buy, it will have a standard type of sealed lead-acid battery in it.  There seems no reason not to buy an engine starter device, especially if you actually can use it for its intended purpose (that compressor is very useful for inflating tyres).

I agree that the cigarette lighter plugs are a bit rubbish. I broke one by tripping over the power lead in the dark.

I also made up a 10x1.2v AA Nicad battery set which worked with my SLT mount and was small and light, but keeping 10 cells charged was a faff.

All the above devices would work for several sessions without needing a recharge (with my mounts).

[Jm1973]

A lot of food for thought. I guess if I was going to go for the easy option I would get a jump-starter, as they seem to be basically the same thing as the SKywatcher powerbanks but cheaper.

My other option is to build something bespoke. I have basic soldering skills. I used to build drones and that involved soldering circuit boards, so something like this should be a doddle. I can certainly follow a circuit diagram. 

I suppose the other option is something more modern like LiPo or LiFePo. Am I right in thinking the main advantage with LiFePo over Lipo is safety? 

[Waldemar]

8 hours ago, Jm1973 said:

I suppose the other option is something more modern like LiPo or LiFePo. Am I right in thinking the main advantage with LiFePo over Lipo is safety? 

This: batteries - LiFePo4 vs LiPo - Electrical Engineering Stack Exchange will tell you the differences.