12v distribution- CCTV Power Supply

[Zakalwe]

Hi guys,

I'm thinking of changing the power distribution that I currently am using and am interested on hearing your thoughts. Currently I use a Maplins regulated power supply for the CCD. A separate 12v PSU (Fusion 200w thing) powers the dew heaters, mount, USB hubs, focus controllers (two Hitec devices). I was thinking of splitting the dew heaters onto their own supply and using the Fusion PSU solely for the mount.

Anyhoo, I found that you can get 12v distribution boxes for CCTV. These seem to look like a good solution- they could be mounted to the pier which would tidy up a lot of cabling. Can anyone suggest any reasons why this would be a bad idea?

https://www.amazon.co.uk/Nordstrand-Camera-Power-Supply-Distribution/dp/B00PRBSVTO/ref=sr_1_7?ie=UTF8&qid=1475829571&sr=8-7&keywords=12v+Power+Supply+Distribution+Box

https://www.amazon.co.uk/Reelva-CAMERA-POWER-SUPPLY-DISTRIBUTION/dp/B01G8GQNUK/ref=sr_1_2?ie=UTF8&qid=1475830079&sr=8-2&keywords=12v+Power+Supply+Distribution+Box

[SkyBound]

Sounds like a good idea to me, also mount a nano PC on there as they run from 12v and you have it all in one, that is my plan anyway, so I will watch thismthread with great interest

[RayD]

These units are good, and I use one for my CCTV system.  However, a couple of issues for AP that I can see are:

1. Whilst the supply is ample, each channel output is relatively small.
2. If you lose 1 supply you've lost everything.  There's no chance to quickly rig up a splitter on another supply to keep your session going.

As far as the technicalities go with regard to harmonics etc. I couldn't tell without looking at the spec. sheets, but the above would be my personal main concerns.

[SkyBound]

One thing I would say, is the fusion power supply you have will be a good regulated one, the ones in the CCTV supply boxes may not be and may cause issues, I have read that these along with PC power supplies aren't that good for imaging kit due to this..

[Zakalwe]

5 minutes ago, SkyBound said:

Sounds like a good idea to me, also mount a nano PC on there as they run from 12v and you have it all in one, that is my plan anyway, so I will watch thismthread with great interest

I've toyed with that but the main stumbling block is that I also do solar work, using an ASI174 camera. That needs USB3 and a decent SSD due to the high framerates. Getting those in a nanoPC tends to be expensive. No doubt, they'll be available for buttons soon enough though.

2 minutes ago, RayD said:

These units are good, and I use one for my CCTV system.  However, a couple of issues for AP that I can see are:

1. Whilst the supply is ample, each channel output is relatively small.
2. If you lose 1 supply you've lost everything.  There's no chance to quickly rig up a splitter on another supply to keep your session going.

As far as the technicalities go with regard to harmonics etc. I couldn't tell without looking at the spec. sheets, but the above would be my personal main concerns.

Losing power wouldn't bother me too much.

The low per-channel output shouldn't be a problem for the focus controllers and  USB hubs. It might be a bit tight for the dew heaters though....I'll need to check this.

2 minutes ago, SkyBound said:

One thing I would say, is the fusion power supply you have will be a good regulated one, the ones in the CCTV supply boxes may not be and may cause issues, I have read that these along with PC power supplies aren't that good for imaging kit due to this..

I'll be keeping the Maplins and Fusion (both regulated) for the mount and CCD camera. My thinking is that separating the "noisy" dew heaters and other kit from the camera and mount can't be a bad thing.

Thanks for the comments guys.

[SkyBound]

24 minutes ago, Zakalwe said:

I've toyed with that but the main stumbling block is that I also do solar work, using an ASI174 camera. That needs USB3 and a decent SSD due to the high framerates. Getting those in a nanoPC tends to be expensive. No doubt, they'll be available for buttons soon enough though.

Losing power wouldn't bother me too much.

The low per-channel output shouldn't be a problem for the focus controllers and  USB hubs. It might be a bit tight for the dew heaters though....I'll need to check this.

I'll be keeping the Maplins and Fusion (both regulated) for the mount and CCD camera. My thinking is that separating the "noisy" dew heaters and other kit from the camera and mount can't be a bad thing.

Thanks for the comments guys.

I have been discussing this in another thread, and I have just bought a nano PC new from eBay for £54 but have to add my own RAM and SSD so with that it has cost around £130 with 240gb SSD and 8gb RAM, the PC is a quad core J1900 intel processor so has enough power. It has 6 USB ports 4x USB 2.0 and 2x USB 3 0

here is a link if you are Interested:

http://www.ebay.co.uk/itm/162213239069?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[martin_h]

For the low power per channel limit could you not connect 2 or 3 channels in parallel to up the current?

[RayD]

1 hour ago, martin_h said:

 

For the low power per channel limit could you not connect 2 or 3 channels in parallel to up the current?

 

You could indeed, but that would negate the point of having this type of power supply.  You would then be better just getting a 10A switch mode supply, chucking it in a box and putting some cigarette outlets recessed in with fused supplies to each.  It would be cheaper and you could change the supply only if it failed in the future.

 

Edit: You could also then put the supply in an IP rated box.  These ones I don't think are IP rated, so are intended for indoor use, which isn't really ideal for AP. 

[martin_h]

4 hours ago, RayD said:

You could indeed, but that would negate the point of having this type of power supply.  You would then be better just getting a 10A switch mode supply, chucking it in a box and putting some cigarette outlets recessed in with fused supplies to each.  It would be cheaper and you could change the supply only if it failed in the future.

 

Edit: You could also then put the supply in an IP rated box.  These ones I don't think are IP rated, so are intended for indoor use, which isn't really ideal for AP. 

Which is exactly what I do, a 24 v one for the roof motor and a 12 v one for everything else... http://www.ebay.co.uk/itm/12-volt-DC-power-supply-enclosed-switch-mode-12V-8-5A-100W-/221233365175?hash=item33828940b7:g:1mYAAOSw3ydVhH4d

[SkyBound]

20 minutes ago, martin_h said:

Which is exactly what I do, a 24 v one for the roof motor and a 12 v one for everything else... http://www.ebay.co.uk/itm/12-volt-DC-power-supply-enclosed-switch-mode-12V-8-5A-100W-/221233365175?hash=item33828940b7:g:1mYAAOSw3ydVhH4d

I was under the impression that switched power supplys were not good for Astro kit.... as there are not well regulated and can spike

[RayD]

3 minutes ago, SkyBound said:

I was under the impression that switched power supplys were not good for Astro kit.... as there are not well regulated and can spike

Depends if you get cheap one which has insufficient filtering and suppression as the switching does create some noise otherwise.  In theory SM supplies are better as they use much less energy and generate less heat, and can therefore be quite a bit smaller.

If a linear power supply is easier to come by then that also would be fine.  It's hard (very hard) to get a totally clean DC supply unless using a battery, or a very very good and very expensive power supply.

My point was these CCTV units aren't really designed for outside use, but a reasonable 10A supply in an IP56 box with AUX sockets would be ideal as you can fuse 1 @ 5A (mount?), 2 @ 2A (Heaters) and 1 @ 1A (whatever you want).  Something similar to what I did with my battery box in the attached image, but with a 220V transformer inside instead of a battery.  Accepted the box would be smaller, such as a Wiska box, but the idea only is what I'm suggesting.

[Pippy]

Be very careful about powering up those switched mode PSU's if their is any possiblity of damp / dew having formed on the PCB.

We had one here which we took apart to see what the mains <> 12V DC physical isolation was like on the PCB (we didn't strip the transformer down to check that). it was mostly OK apart from the PCB layout designer having brought the mains DC supply within about 1mm of the 12V DC output, the silly berk .. bridge that with damp / dew and something will give at some point - the PSU, the connected equipment and/or yourself - "give" as in bang, smoke and / or electrocution.

So becareful with those metal meshed switched modes.

[martin_h]

2 minutes ago, Pippy said:

Be very careful about powering up those switched mode PSU's if their is any possiblity of damp / dew having formed on the PCB.

We had one here which we took apart to see what the mains <> 12V DC physical isolation was like on the PCB (we didn't strip the transformer down to check that). it was mostly OK apart from the PCB layout designer having brought the mains DC supply within about 1mm of the 12V DC output, the silly berk .. bridge that with damp / dew and something will give at some point - the PSU, the connected equipment and/or yourself - "give" as in bang, smoke and / or electrocution.

So becareful with those metal meshed switched modes.

Mine is in the warm room and in an IP rated enclosure with all cables in and out through glands.

[Zakalwe]

1 hour ago, Pippy said:

Be very careful about powering up those switched mode PSU's if their is any possiblity of damp / dew having formed on the PCB.

We had one here which we took apart to see what the mains <> 12V DC physical isolation was like on the PCB (we didn't strip the transformer down to check that). it was mostly OK apart from the PCB layout designer having brought the mains DC supply within about 1mm of the 12V DC output, the silly berk .. bridge that with damp / dew and something will give at some point - the PSU, the connected equipment and/or yourself - "give" as in bang, smoke and / or electrocution.

So becareful with those metal meshed switched modes.

A very good point. Bigclive.com regularly pulls Chinese stuff apart ond the lack of isolation in some of the stuff that they pump out is extraordinarily bad.

I've gone from the CCTV box to plans for an IP box with a built in nano-PC. No doubt apathy will kick in over the weekend and I'll end up with an IP rated box, a 4 port mains extension lead and a few plug in wall-art transformers.

[Pippy]

Yes. Well, when it comes to having PSU's in damp places / outside, I'd always prefer a less efficient (power comsumption wise) and physically bigger linear PSU (they also generate no HF noise). Sooo much more safer.

[SkyBound]

2 hours ago, Zakalwe said:

A very good point. Bigclive.com regularly pulls Chinese stuff apart ond the lack of isolation in some of the stuff that they pump out is extraordinarily bad.

I've gone from the CCTV box to plans for an IP box with a built in nano-PC. No doubt apathy will kick in over the weekend and I'll end up with an IP rated box, a 4 port mains extension lead and a few plug in wall-art transformers.

That's my plane too, as USB extensions just don't seem to be cutting it for a lot of people, so. Nano PC at the mount is the way forward, and then with teamviewer installed in host mode, it can be controlled from another PC in the warm somewhere.

it will have to run in host mode as there will be no monitor, mouse or keyboard connected to mine.

The nano PC I ordered should be here tomorrow...

[Zakalwe]

12 hours ago, SkyBound said:

The nano PC I ordered should be here tomorrow...

I am interested to hear how you get on, particularly if it can cope with a modern planetary cam. My ASI1600 generates massive USB traffic.

[SkyBound]

53 minutes ago, Zakalwe said:

I am interested to hear how you get on, particularly if it can cope with a modern planetary cam. My ASI1600 generates massive USB traffic.

Hmmmm

not sure it will cope with that to be honest 

i only have the ASI120mc-s USB 3.0 version for planetary, should cope with that ok, but my main interests is deep sky, with my newly acquired Atik 383L+ mono, I looked as the ASI 1600 but this 383 came up for £795 so could not resist, and its mint..

it has arrived but still waiting for the hard drive and RAM, but will keep you informed, it also has a mini serial port, so ordered the cable for that too, so I can connect my mount direct without using a USB to serial adapter, and so giving me another free USB port.

[SkyBound]

Well here is a few i boxing images, all very well and professionally packed, all tools included, and software on a USB memory stick, certainly looks better than £54 worth...., proof will be when I get it all up and running.