Powering printers without mains

[Billy Whizz]

Paul

Adventure Racer has pointed the way. Take a second car battery (could be in an adjacent car); link in series and power the printer directly, providing 24v. The car batteries will supply 2amps (peak demand only as previously observed) for longer than you'll need. Any laptops can be powered from the inverter (v small current drain).

[Paul Frost]

The problem is how to then connect the 24v supply to the printer which has a weird 3 pin din type power socket.
But the whole idea was to have a quick, simple easy to use setup. So lining up 2 cars, cables between them etc. is way too complicated.
It looks like a slightly higher wattage inverter should solve the problem and keep things simple.
So thanks for all the advice and helping me understand the issues.

[Adventure Racer]

The problem is how to then connect the 24v supply to the printer which has a weird 3 pin din type power socket.

Ah! I was assuming a standard jack connector, hence my suggestion being plug and play. Thought about suggesting the dual battery approach, but reckoned that was more complicated. If it was mine I'd get out a soldering iron and rewire the connector (it's probably something fairly standard which you could get a spare for rather than hacking apart the existing power supply), though probably not a realistic option for you.

[SIman]

We have bought a 40Ah battery with integral 300W invertor, £110 from Halfords, which does very well for any event which doesn't need a laser printer.

[Paul Frost]

I've done a few more tests and someone has given me a 75Ah leisure battery.
I now suspect that the mains lead/transformer for the printer may be faulty.
I tried connecting my laptop which has a similar 1.6A rating and it works fine, even in the lighter socket.
So my next question is there any way I can test the questionable mains lead?
It works fine when plugged into the mains.

[Adventure Racer]

If it works fine plugged into the mains, then it probably is fine. The issue is almost certainly as I suggested before, that the printer transformer has a large inductive component which the inverter doesn't like, whilst the laptop power supply is far more like a resistive load - I'd expect a laptop power supply to have a much cleaner loading on the mains given the whole thing is likely to be more sophisticated.

[Wayward-O]

Something like this:

https://www.voltageconversion.co.uk/sto ... ctid=16308

would enable you to run 24V equipment direct from a single 12V battery, cutting out the inverter / transformer problem.