12v DC power next to USB?

[michaelmorris]

I'm soon to be installing a new regulated linear 12v power supply in my observatory.  The present switched 12v supply is much smaller and hence has room to be mounted on the side of the pier.  The new 10A/12A linear supply is much heavier and bulkier and will have to be mounted away from the pier.  At present, my two main USB leads run from the pier to the computer in a piece of trunking in the floor of the observatory.  This would be by far the easiest way to route the 12V to the pier.  Is laying 12V cable next to the USB leads likely to cause any problems?

Thanks

[Davey-T]

I've got 12volt camera supplies and USB camera cables all bundled together in trunking going to the mount, had no problems, so far 

Dave

[Juicy6]

No, no problems. If you are replacing a modern switch regulated supply with an old fashioned linear with big transformer, big electrolytes and maybe one or two power transistors on big heat sinks, you are in fact at less risk being exposed to interference. Modern switch suplies CAN be built badly with much interference being emitted, with noise often heard several MHz up the short wave bands. Usually old regulated linears are better. But both types present no problem to a hobby astronomer.

Christer

[michael8554]

Hi Michael Morris

DC is no problem, chopped DC from a dew heater controller probably would be, but I assume your controller is on the mount or OTA.

Michael8554

[Dr_Ju_ju]

Depending on how far away the supply is sited, and making sure you are using good quality cable (I personally rate the cable for at least double the expected load), then there should be no issues.

[RayD]

The issues with differing voltage parallel cable runs are generally EMF induced transients and voltage peaks, but at 13.8v and 5v this is highly unlikely to be an issue, so you will be fine with these run together.  Best practice says where they are running parallel for a distance, just move them apart in the trunking, but the EMF at 13.8v 12A really isn't very big at all, so no need to bust a gut to do it.

[michaelmorris]

Thanks folks. I've ordered some 15A cable for a 10A power supply.