electric protection

[the snooper]

I work on timber harvesters and forwarders and the electrics must be isolated AND fitted with a surge protection when welding. If you don't they wreck the very expensive computers on these machines so there must be something in it.

i would imagine its more a precaution if they are that expensive

 

[brightspark]

I work on timber harvesters and forwarders and the electrics must be isolated AND fitted with a surge protection when welding. If you don't they wreck the very expensive computers on these machines so there must be something in it.

probably just to cover there a..ses it wont be any diffent to getting static build up on the machine , just do what u think best and are happy with doing

 

[rtbcomp]

............... The welding output should be floating.

The electrical term is isolated.
............

"Floating" is used to describe a power source that has neither of its outputs connected to anything else. Most commonly used in bench power supplies to allow several outputs to be connected in series to increase the voltage.

 

[blenkie1]

No it's more than a precaution they do actually fry the computers. It's a big no no to actually start welding on the machines with the computers switched on. Been a few expensive mistakes before I started. Suppose it just matters how sensitive the electronics are. Spent years welding wagon bodies and never had to isolate or fit surge protection

 

[brightspark]

No it's more than a precaution they do actually fry the computers. It's a big no no to actually start welding on the machines with the computers switched on. Been a few expensive mistakes before I started. Suppose it just matters how sensitive the electronics are. Spent years welding wagon bodies and never had to isolate or fit surge protection

i wouldnt have thought anyone in there right minds would leave them on and start welding it would be like me testing household wiring with a megger and the satelite box and freeview plugged in .they deffo fry when u do it

 

[Robotstar5]

it would be like me testing household wiring with a megger and the satelite box and freeview plugged in .they deffo fry when u do it

With the amount of electronics plugged in these days it's best to err on the side of safety and do L/N to E unless you're fault finding. My favourite is the TV amp still plugged in the loft

 

[brightspark]

With the amount of electronics plugged in these days it's best to err on the side of safety and do L/N to E unless you're fault finding. My favourite is the TV amp still plugged in the loft

ive duffed a few in in early days one box was only a month old . women got the guy out to fix it under warranty and he asked if they had been any lightening that day i was earwigging in the other room err no i just put 500v down the line

 

[ajlelectronics]

No it's more than a precaution they do actually fry the computers. It's a big no no to actually start welding on the machines with the computers switched on. Been a few expensive mistakes before I started. Suppose it just matters how sensitive the electronics are. Spent years welding wagon bodies and never had to isolate or fit surge protection

Sorry, don't believe it. There is no path for damage. Sounds like A covering.

 

[Sidewinder]

"Floating" is used to describe a power source that has neither of its outputs connected to anything else. Most commonly used in bench power supplies to allow several outputs to be connected in series to increase the voltage.

I disagree rtbcomp.
A welding transformer is isolating, not floating.
If you refer to the design, test & inspect BS's you will see what I mean.
If you like I can get you excerpts from these to explain the requirement for the units to be sole legally in the EU.
Thus the safety requirements.
I have the standards on my HDD here.

 

[brightspark]

small portable generators have a floating earth thats about it .its not an isolating transformer as in a welder

 

[rtbcomp]

I disagree rtbcomp.
A welding transformer is isolating, not floating.
........

The transformer is isolating, its output is floating.

 

[Sidewinder]

The transformer is isolating, its output is floating.

rtbcomp,

I think this could go on for ages, as I don't think I explained what I was on about correctly, nor did I understand from the posts you made what you were trying to say.

I guess you could say that the output is floating, though to be honest, it is not a term I like in this situation.

I would prefer to say that the output of an isolating transformer is floating with respect to true earth.

However, the output pair are not floating wrt each other, they have a defined and fixed output characteristic.

Perhaps we were trying to say the same thing in different ways, just that over the forum it is not always easy to always understand exactly what people mean.

 

[Turbo]

I used carry out TIG repairs on food production machinery. Anything that was controlled by a PLC or had a vfd installed had to be powered down for 5 minutes and isolated from the supply before any welding took place. On one machine you had to disconnect the vfd completely. A collegue forgot one day and fried the vfd, costing a new vfd at £1500 and 2 hours downtime on the production line! He got a roasting from the boss and was lucky to keep his job!

 

[Richard.]

Most important thing I'd say is not mentioned yet. If you do disconnect the battery on the motor, if it's a coded radio make sure you know it (done that before)
Just my ten pence worth. Carry on

 

[daleyd]

I worked for 9 years on industrial dryers and thermal oxidisers (plc controlled and inverter drives) and the only thing we ever did was to turn off the power before any welding( usually had to be locked off anyway due to whatever companiy we were working at safety regs). Never had any issues, though even when we weren't doing any welding things sometimes didn't like to start up again after being off for a while!

 

[Richard.]

I used to do quite a lot of SAW automated and golden rule number 1 was direct earthing to avoid current travelling through bearings.

 

[optima21]

all the years Ive been MIG welding my cars I've never unplugged the battery, but I did when I got my TIG welder, because I wasn't sure if the HF start would cause any issues The HF start causes my head torch to switch on if its within 2 metres of me when Im using the TIG. took me a couple of times before I worked out what was happening, as Idont get any interference on the radio I listen to.