DIY Power panel.. The return !

[Gina]

With 12v DC I don't see that it makes any difference which connection is which on a fuseholder but with a mains fuse you don't want any possibility of getting a shock if the power is on so the rear connection wants to be connected to the live (line) side of the supply.  The fuse should be in the line rather than neutral.

[Alien 13]

The only issue with mains fuse holders and indeed the fuses is that the contact resistance in a 12 V system can become significant even more so with age and temperature it might be a few tens of milli ohms but can be enough to drop a few hundred milli volts or more if it is subjected to a significant load.

Alan 

[Vox45]

On 26/04/2016 at 10:48, Vox45 said:

Good news (for me at least) ... it was a bad case of Murphy's law !

After pondering for quite a while on what the problem could be, I went back to basic troubleshooting: "start from the outlet".

So I did. I tested every connection in my powerpanel and the cig ligther. Everything was fine, so I moved on to the cord itself by doing a continuity test ...

Lo and behold, the continuity test failled ! I opened up the cig light plug and this is what I found:

Quick update on this. A friend of mine was travelling to Dallas for work so I ordered 3 Marinco 12VPG SeaLink Deluxe Marine 12-Volt Plug (Black) at 10$US a piece (instead of a ridiculous 43€/each on Amazon France)

Got them this morning, I will change the plug on the mount and HitecAstro focus box... I am keeping one as a spare, I may sell it to finance the other 2's later on  

[ChrisLX200]

You can buy them off Ebay.. http://www.ebay.co.uk/itm/291171331824?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT  ;-)

ChrisH

[Vox45]

On 17/05/2016 at 17:04, ChrisLX200 said:

You can buy them off Ebay.. http://www.ebay.co.uk/itm/291171331824?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT  ;-)

ChrisH

The one you linked to are rated at 8A with a 5A fuse supplied. The one I got are 10A. They do look the same... pfff hard to tell as sometime the advertising picture do not match... Anyways, thanks for the link

[Vox45]

Done!

The device is now working properly and attached to the mount. I can power everything and there are only 2 cables dangling from the mount, power lead to battery and the USB extension. Next step will be adding a Raspeberry PI and use either an Ethernet cable or USB extension. Using the RPI WIFI would leave only the battery cable ...

Just a bit of aesthetic modifications needed on the protective case...

 

[Vox45]

I was unhappy with the way the powerpanel was attached to the mount ... I could not get a smooth meridian flip with cables getting stuck and the case moving around.

Not a good idea, so I went back to the drawing board

This design is way better. The box being very light it act as a counter weight to the guide scope. No problem balacing the whole thing.

This is the naked design as a proof of concept, I'll add the protective case tonight and work on the placement of cables.

The end goal is that I can remove the scope/cables/distribution box in one go after unplugging the mount/EQDIRECT/DSLR. This should simplify tenfold setting up and tearing down !

[Gina]

This is the sort of think I want to do.  Saves having either lots of cables floating around or putting them all in the umbilical.

[Physopto]

I did a similar thing a while ago, but machined up aluminium bars to fit across the Losmandy plate and  hold the connection boxes. I have one either side, held on with 5mm hex head bolts. That way you do not have to loosen off the scope clamps to remove or fit them. The photo was when testing before I tidied up the wiring with a loom.

Derek

[Vox45]

1 hour ago, Gina said:

This is the sort of think I want to do.  Saves having either lots of cables floating around or putting them all in the umbilical.

I was giggling like a schoolgirl last night when doing meridian flips over and over again ... everything was rock solid, no dangling cables and not an ounce of tension on any piece of equipement connected.

But imagine my joy when I realized that I could just remove the scope with all cables attached and put it back in less than 2 minutes! For a nomade astronomer, that is really cool. No cables to untangle or plug in the dark or in the cold...

Pure bliss

I'll add some pictures when the protective case is finalized...

As I was trying to share my enthusiasm with my better half, she noticed that the case is black and white like my setup and it makes it pleasing to the eyes... although she is right and that I failled to notice it before, we clearly don't have the same appreciation for my top-notch craftsmanship.

[Vox45]

Since I am now using a Raspberry Pi with my powerpanel, I decided to add a relay board to my project.

The end goal is to be able to cutoff current to 4 of my devices: the focuser, the DSLR, the USB hub, the mount.

This will give me the ability to turn on and off different devices if needed (reboot of the device) or turn off for a period of time when not needed (focuser for example)

(8€ from amazon)

 

 

 

[Vox45]

Quick update on this thread. Here is the finished look and a demonstration of the power panel in action using my DIY bench power supply and a laptop running Linux and INDI Kstars/Ekos

I am quite please with the result and would like to thank all those who have contributed to this thread as your help and advices have been invaluable

 

[Physopto]

2 hours ago, Vox45 said:

Quick update on this thread. Here is the finished look and a demonstration of the power panel in action using my DIY bench power supply and a laptop running Linux and INDI Kstars/Ekos

I am quite please with the result and would like to thank all those who have contributed to this thread as your help and advices have been invaluable

 

Very nice job. I am sure it will make life a lot easier for you.

Derek

[Vox45]

Thank you!

I really like the fact that all the connectors and cables are protected in the nylon case and the low warmth that is generated keeps everything free of condensation.

Also, having only 2 leads from the mount is much easier to manage ! The ultimate goal is to eliminate the data cable using only WIFI to the RPI3 (the PI act as an access point) I've done some tests but I did experience some speed issues.... more tests needs to be done

The nice thing about the PI is that I was able to fit a relay board so I can turn on/off my mount, the powered hub, my DSLR and the focuser... I know, I know, I am only a few feet away but that is nice

[BRUN]

@Vox45 sorry if its already been said, but what size fuses are you using, how many amp ?

[Vox45]

18 hours ago, BRUN said:

@Vox45 sorry if its already been said, but what size fuses are you using, how many amp ?

That would be:

Pixnor 5x20mm fast acting fuse and 5x 20 mm fuse holder. I chose the amp according to each device connected and a 10A fuse for the main.