12v socket making lights flash

[Loafer]

Why have you fitted a rectifier?

 

I'm not sure he has.

 

What have you put in there Tommy?

[tommyleyland]

I've been told to fit a 12v rectifier (I got one from a motorcycle) to make sure when charging my laptop via the 12v charger whilst the engine is running it doesn't damage the laptop. Is this correct?

[Boredrider]

A 12v rectifier from a motorcycle is used to get DC (Direct Current) from an AC (Alternating current) source, such as an alternator. If you fitted the 12V socket to the batteries then you should not need a rectifier, as the supply from the batteries is already DC. If the laptop charger is designed to work off a cigarette lighter socket in a car, then it won't be damaged when your engine is running, as it is designed to work off the sort of voltages produced by a car alternator (say up to 14.5 volts or a little more).

[Loafer]

Sounds to me like the advice to fit a rectifier was a 'bum steer', as we old aviators say. Or the advisor wasn't fully appraised of your set-up.

 

2p.

[Paul C]

Maybe he means (and I don't know the official terminology for one) "voltage stabiliser" which is designed to limit the voltage to 12V or a little over, rather than the possibly wider variation of a 12V electrical system of a boat during charging/discharge etc. An adapted laptop PSU might not be tolerant of a wide voltage range and need this.

 

Having said that, I've never used one and although there's been plenty of threads on them, never been sufficiently interested. Instead, I use a small inverter and the laptop's normal power supply. Someone did power measurements and there was no gain in overall efficiency over the inverter+PSU route.

[tommyleyland]

Oh right, makes sense. I'll leave the rectifier off in that case