12V power to multiple devices and 5V

[rnobleeddy]

Figure this might be the best place to ask this. 

I'd like to sort out the mass of cables I have. I have a bunch of stuff in a waterproof box beneath the mount and cables running to the mount. Powered from the mains with a 4-way adapter and 4 separate power supplies. With the dew strap needing to be a thing now, I've decided I'd prefer to mount everything alongside the OTA, especially as I now have a mount that can take the weight.

I need 3 x 12V outputs (EQ6 mount, dew controller, focus controller) and 2 x 5V outputs (Raspberry Pi + powered USB hub) and probably some room to have some more kit in future. I tot that up to around 3A at 12V and maybe 5A at 5V (as this powers my Canon Camera too). 

Current plan is to use an outdoor rated 12V PSU such as https://www.amazon.co.uk/Idealyuan-Waterproof-Transformer-Adapter-Lighting/dp/B07JP15KTG/ref=sr_1_6?crid=UF7D8GRFRMMZ&dchild=1&keywords=12v%2Boutdoor%2Bpower%2Bsupply&qid=1601935128&refinements=p_76%3A419158031&rnid=419157031&rps=1&sprefix=12v%2Boutdoor%2Bpowe%2Caps%2C140&sr=8-6&th=1 (although if I can find something more reputable that's not too expensive, I'll swap for that). I figure that apart from the lottery that is unbranded chinese hardware, it has plenty of headroom even if I do need 8A at once.

I was then planning to just naively split the 12V (e.g. something like https://www.amazon.co.uk/kenable-Power-Splitter-Adapter-Camera/dp/B06XXCDLK1?th=1) and then a couple of 12V to 5V converters (e.g. https://www.amazon.co.uk/Converter-Step-Down-Power-Supply-Black/dp/B009P0504M). 

I figured I'd also add something like https://www.amazon.co.uk/Akozon-Analyser-0-100A-Precision-Analyzer/dp/B07L9WCD9H to keep track of power usage.

I'm happy that providing the PSU is good for outdoors, any mains plugs are joined in outdoor rated boxes, and I use an RCD, I probably can't kill myself.

My main question is if there's anything better, and if I should worry about running everything off the same power supply? I'm far from an electronics expert but as I understand items like the dew heater may cause feedback and therefore reduce the quality of the power to the places it matters (e.g. the mount and Pi). Having two smaller PSUs would also be an advantage from my current situation. 

I guess what I really want is https://www.altairastro.com/pegasus-astro-pocket-powerbox-advance-power-supply-2846-p.asp but I can't bring myself to pay that much for a PSU!

Edited October 5, 2020 by rnobleeddy

[MarkAR]

Get the Pegasus Ultimate PB, it will save a ton of messing and stray cables. If you're using Stellarmate or EKOS it will talk directly for complete control through the Pi as a server.

There's another thread about a couple of add on boards for a Pi that will give you power and dew.

 

[bottletopburly]

I use the deepskydad power hub2 

https://deepskydad.com/dchub2

[rnobleeddy]

2 hours ago, bottletopburly said:

I use the deepskydad power hub2 

https://deepskydad.com/dchub2

Thanks. I ordered one of these. At around £60 including postage, it seems like a decent bit of kit for the price.

[bendiddley]

On 06/10/2020 at 09:07, rnobleeddy said:

Thanks. I ordered one of these. At around £60 including postage, it seems like a decent bit of kit for the price.

Hi. I stumbled upon this post whilst researching 12v hubs. Just wondered how you got on with the deepskydad box? Thinking I would quite like something similar to this. Cheers.

[rnobleeddy]

23 hours ago, bendiddley said:

Hi. I stumbled upon this post whilst researching 12v hubs. Just wondered how you got on with the deepskydad box? Thinking I would quite like something similar to this. Cheers.

The only negatives are that it took a little while to arrive (maybe 2.5 weeks) and the finish isn't as professional as the more expensive alternatives (i think it's 3d printed).

Definitely recommend it - it's great value for money. I've used it with a few different setups and must have been drawing close to the maximum current a few time and it's been rock solid. I power everything from it, including the mount, raspberry pi, camera, dew strap and focuser.

[bendiddley]

3 minutes ago, rnobleeddy said:

The only negatives are that it took a little while to arrive (maybe 2.5 weeks) and the finish isn't as professional as the more expensive alternatives (i think it's 3d printed).

Definitely recommend it - it's great value for money. I've used it with a few different setups and must have been drawing close to the maximum current a few time and it's been rock solid. I power everything from it, including the mount, raspberry pi, camera, dew strap and focuser.

Cool sounds good. I might give this a go. I'm weighing up options at the moment, even considering making my own one, have started another post to find out more about that, if the price is right though I'm all up for buying a ready made hub as I'm not very electronically minded, but up for a challenge too if needs must