Power options

[iapa]

Has anyone tried one of these? https://smile.amazon.co.uk/Redrex-Universal-Regulated-Switching-Transformer/dp/B01MRSAT39/ref=pd_day0_hl_60_4?_encoding=UTF8&pd_rd_i=B01MRSAT39&pd_rd_r=063bf7d7-decf-11e8-9244-bbcc5e42676d&pd_rd_w=Mk4MT&pd_rd_wg=IRUpq&pf_rd_i=desktop-dp-sims&pf_rd_m=A3P5ROKL5A1OLE&pf_rd_p=b082d07b-aaea-4f40-9ff3-d27463f747d7&pf_rd_r=EP80BX38VBJDBV3QV4AZ&pf_rd_s=desktop-dp-sims&pf_rd_t=40701&psc=1&refRID=EP80BX38VBJDBV3QV4AZ

or their equivalent

It looks to be suitable to feed a multi port power distribution - a bank of RCA connectors maybe?

[symmetal]

I use a similar design for powering my dual imaging rig, though mine's a UK made one so cost quite a bit more. I've put some filters in the outputs depending on what it's feeding to minimize noise though on tests with my CCD camera there was no difference in image noise level with or without the filters and was the same as powering it off a battery. You'll need to put it in a suitable case of course. They are a single output with the screw terminals commoned to spread the current load.

However I wouldn't use RCA connectors as output connectors apart from on dew strips as that's normal for them. The connection is not very robust, particularly the screen (ground) and aren't designed for significant currents.

Alan

[adyj1]

2 hours ago, iapa said:

Has anyone tried one of these?

I use something very similar, rated to 10A.

I run female XLR sockets for the various 12v devices and then step down to 9v and 6v as required and use different connectors (one is male XLR socket, and another is 5.5/2.1mm dc power leads). All outputs are individually fused, which is probably overkill... 

All in a nice big box which has room for my bare-shell mini PC and astroeq control box.. 

Ady

[mikeyj1]

+1 for the XLR's, and the PSU: I have the same 20A version powering everything (Scope, Computer, Cameras, Dew control and three bands, telrad dew-heater)

[iapa]

belt and braces

I order 3 of the PSUs

A reel of cable and some screw connect 2.1mm connectors - proof of concepts.

If the PSUs prove to be reliable I'll look at putting the three in parallel with some control circuitry.

 

Re RCA, I mentioned as I happen to have a few dozen of these in various colours, and it's intended to be a permanent set up, so plug/unplug is likely to be low

[adyj1]

4 hours ago, iapa said:

Re RCA, I mentioned as I happen to have a few dozen of these in various colours, and it's intended to be a permanent set up, so plug/unplug is likely to be low

I think the main concern was the current rating for RCAs, (esp if you're putting 60A (!!!) up for grabs...)

Ady

[symmetal]

That's certainly belt and braces. 

Most 'higher quality' RCA (phono) connectors are gold plated. Gold plating is used on contacts where the currents are small, in the range of a few mA, as the gold doesn't tarnish and so a reliable connection is made. The plating is very thin. Plugging and unplugging DC connectors carrying significant current will likely cause a small arc as the contact is made or broken. This arc would burn off the very thin gold plating where it strikes. The higher the current the bigger the arc. Gold is also soft so is easily worn away.

Connectors used for DC power connectors are usually silver plated (like XLRs) as silver is a better conductor than gold (less resistance) and is also harder. The plating can also be thicker. Silver does tarnish when exposed to air causing a higher resistance but the higher currents used in DC power connectors 'burns' through the tarnish to maintain a good connection.

Using phono connectors for dew straps is because they are cheap and easy to make. A poor connection there isn't a serious problem but for a mount or camera it would be a real pain.

Alan