Welding/electronics

[steamguy56]

Now I know the two don't mix...but having pulled all the neg. posts on the batteries, done a few welding tasks, The question that I have is, can any thing be harmed (ddec? 1997 prevost series 60,12.7) with all the power shut off for extended time. 2 weeks

[edroelle]

The service manual says to disconnect all electronic boxes - DDEC, ATEC, Webasto, etc.  Your welder has a ground to the chassis.  Each of those boxes do also.  Maybe you can get away without disconnecting them, but at the replacement price, I would not gamble and create a problem.


Ed Roelle

[TrevorH]

When you hook the welder up to the frame, or whatever you are welding for that mater.  You provide a ground for the structure.  It could in theory damage electrical components.  I would not chance it and would disconnect all battery cables.  It would be really frustrating to not only cook something but the process of trying to find exactly what got damaged could be very tedious.

[belfert]

Also be sure to disconnect the ground on any Vanner equalizers.

My Dina manual says to remove the fuses for the DDEC and the WTEC before welding.  I can't find the fuse for the WTEC so I just remove the wiring harness from the WTEC itself.

[Sammy]

Steamguy,
Nothing will happen if you leave the bus powered down for 2 weeks, with the batterys disconnected.
Engine computer (DDEC), trans computer (WTEC) and the ABS computer will all be fine.
Hopefully you didn't damage any of them during welding.
All computers should have their connectors removed too,before welding.
DDEC ECM is mounted on the curbside of your Series 60, WTEC ECU is in the electrical compartment on the streetside - at the rear, mounted on the forward wall, and the ABS ECU is in the first cargo bay on the streetside, mounted in the forward area.
I wrenched on H3's and XL2's for 10 yrs.The H3 is my personal favorite.

[niles500]

DDEC

http://www.ddcsn.com/cps/rde/papp/SID-3F78AAA6-3C61B611/pgo_epa07/rdedirect://host/cps/rde/xbcr/ddcsn/Ch_1_2.pdf

ATEC

http://www.allisontransmission.com/servlet/DownloadFile?Dir=publications/pubs&FileToGet=ST2067EN.pdf

[Kristinsgrandpa]

  Another caution about welding,other than the alternator and speedometer on mine, is to get out the leaf blower and get all the leaves out from under the coach.

Ed

[HB of CJ]

Yeah, about the same answers.  Two things here, one is the good chance the coach may burn to the ground.  Crazy things will trap, hold and enable an ember to linger and do its thing.  Stretching in with a two and one half is not a good option inside a coach.  Fire will find a way. Welding is sparking.

Other thing is that continunity is a fickle thing and if it can find a way, it will.  I for one would disconnect ALL of the electrical electronic stuff including both battery cables.  Prohibit all sources of a short.  Having said all of this, I for one don't have the welding skills, sossss nuts and bolts work too. 

[JackConrad]

Regarding fire risk when welding, always have a water hose and a portable fire extinguisher handy. When you finish welding for the day, alow enough time to hang around for an hour to be sure a fire does not start from a smoldering ember. Jack

[Dallas]

One more caution on welding.....

The fiberglass insulation used in your bus doesn't burn, BUT, The crud, crap and corruption that's caught in it will. It only takes one small piece of slag to catch in the black coated insulation to start a great big fire. It will also smoulder for hours and hours.

I accidentally caught some when I was redoing an MC9. I pulled it out while it was smouldering and left it laying onthe ground to see what would happen. 3 hours later, it was still smouldering and slowly growing bigger.

DF