SatNav in lighter socket and 'surge' risk before engine running?

[Bookman]

Hello

I have a Navitel SatNav. The instruction book advises: To protect the device from sudden surges in the on-board power supply, always connect the car adapter only when the engine is on.

Is this a common piece of advice from manufacturers? I presume it means do not plug the satnav into the cigar lighter socket until the engine has started or you risk frying something in the circuit board. Unfortunately, neither my car's socket nor the satnav's plug come with an on-off switch/button, so this means mechanically plugging and unplugging the unit which in my experience wears things out and eventually leads to a bad connection.

I know there are on-off lighter socket accessories out there, and it looks like that's the only option.

 

[Nuvi-Nebie]

Most satnavs run off 5 Volts via a 12 / 24 Volt to 5 Volt USB car charger, does your Navitel have one of these?, this device should also protect your unit from any power surges created when the car is started

 

[Bookman]

Thanks for the reply. I think so -- it's this one: (page 2 and 7)

https://findinstructions.com/instructions-for-navitel-re900-lifetime/download/

But the thing is that the instruction book gives that warning, so I am a bit worried.