12v circuit on hook up for tv

When on EHU any 12v item still runs on 12v but your leisure battery recharges courtesy of the mains EHU .

Assuming you have a TV that can run on 12V or on 240V with a power adapter, on EHU you have a choice. My preference would be to use 240V, it spreads the load between the onboard 12V supply and your power adapter.

When I looked at the failure rate of electronic equipment, mains powered adapters had the highest failure rate. The days of us using a big and heavy transformer in a PSU are in the past and now replaced by switch mode units with lots of components that can fail, more so if they run hot. I've repaired two mains USB chargers when a capacitor inside has popped its top, other switch mode PSUs just went in the bin for recycling.

Spread the load and occasionally feel how hot a switch mode supply is running, it may give you some warning if it might fail soon. At least you can make sure it has good ventilation and not covered up.

Hi  

Peter Brown wrote:Its always best to connect the tv to 12v.  When fully charged the battery charger float charges the battery - effectively supplying all the power to the 12v devices whilst maintaining the battery fully charged.

Absolutely agree, no battery drain from the 12V system on EHU, and apart from any other considerations if you have a 230V TV you can only use it when you have an EHU.

Relaxez-Vous wrote:When I looked at the failure rate of electronic equipment,  mains powered adapters had the highest failure rate. The days of us using a big and heavy transformer in a PSU are in the past and now replaced by switch mode units with lots of components that can fail, more so if they run hot

I seriously doubt is the small load of a modern TV will affect the reliability of a van’s PSU/charger. Reliability is an “extremely” complex subject so I don’t think we can do it justice on a forum like this but a couple of points.

OK a 12V TV on EHU will be powered from the “probably” switch mode van charger but a mains TV will be powered from an internal switch mode power supply.
So either way power comes from a switch mode supply. It’s just that one’s external and one’s internal.

Even in the old large mains transformer based power supplies the capacitors used to fail and the transformers had a tendency to overheat and blow an internal fuse (or just smoke).

Brod