People without knowledge sometimes offer advice.

This is often advice without knowledge.

It is irrelevent whether you disconnect the battery or not.

What is important is the earth path.

When you wish to electric weld, it is vital that the earth connection for the welder is directly onto the part you wish to weld.
This ensures that the current path is only via the part to the welding electrode.

Keeping the battery connected may reduce the possibility of electrical damage, since it limits the magnitude of any induced spikes.

disconnecting batteries can cause more problems than its worth, lost radio codes , windows, sunroofs, alarms ,drive parameters, and adaptive learn stuff losing thier programs.
If you are worried use a surge protector across the battery.

Just out of interest.
How many exhaust shops disconnect the battery or isolate anything?
They just put a good welder earth close to the area being welded and unplug sensors in the system.
The above is based on a few observations.


Adrian VW Amarok 2014 Highline auto

I have not welded anything with the complex electronics like a rangy, but when i was working in the garage we allways used to use a surge protector clipped on the battery and as said before make sure you have a nice clean earth.

This is what we had; http://www.dropshiponline.co.uk/product_info.php?products_id=3664

Now if it does anything or not i couldnt tell you, but we had one so why not?

I have worked on the development of automatic welding systems and we have had our fair share of fried PCBs that cost a cool 5000 GBP each at the time.

Electrical current always chooses the path of least resistance and by taking away all of them, the ground clamp is left. Having the ground clamp on a clean surface is also very important as it affects welding voltage as well (and in pipeline welding that is a big no-no). Another is stray arcs and they are even a bigger no no as they do some serious damage to the pipe surface (and cutting out pipe joints on vessels that cost somewhere between 250,000 and 1 million USD per day, that is not appreciated at all).

My point is, don't take any risk, the cost if it goes wrong is just not worth it (to me). MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!