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Welding Work Effecting Skid Cable

07/14/2011 5:50 AM

Dear all pro,

I got one metering skid at site and it already hook up to the platform, the contractor say one of my instrument cable burn due to welding works.

The burn is not form the welding spark.

And the reason is "no proper grounding"

Anyone can advice me how it can occurs??

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#1

Re: Welding works effect the others skid cable

07/14/2011 5:58 AM

Too much current in the cable, brought on by the welding current?

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#2
In reply to #1

Re: Welding works effect the others skid cable

07/14/2011 6:04 AM

My metering skid not connected yet with power cable.

The platform now in construction phase, so the welding activity is anywhere.

Im not really sure how it burn the cable...the reason=no proper grounding

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#3
In reply to #2

Re: Welding works effect the others skid cable

07/14/2011 6:27 AM

Yes. Some pillock didn't earth the job properly before welding, and the return current has used the instrument cable instead.

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#4
In reply to #3

Re: Welding works effect the others skid cable

07/14/2011 8:50 AM

Where can i find the case study or information regarding this matters?
Or can you explain in details how this happens.

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#5
In reply to #4

Re: Welding works effect the others skid cable

07/14/2011 9:23 AM

LOOK AT IT!

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#6
In reply to #3

Re: Welding works effect the others skid cable

07/14/2011 10:33 AM

I agree: with the information available this sounds the most likely cause. Good diagnosis.

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#7
In reply to #6

Re: Welding works effect the others skid cable

07/14/2011 10:52 PM

This is only cable burn due to the welding (no proper grounding) any advice??

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#9
In reply to #7

Re: Welding works effect the others skid cable

07/15/2011 4:19 AM

Replace it <sigh>.

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#8

Re: Welding Work Effecting Skid Cable

07/15/2011 12:25 AM

Do all the welding before any of the wiring.

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#10
In reply to #8

Re: Welding Work Effecting Skid Cable

07/15/2011 4:46 AM

Which situation make the welding works effected the cable? Any idea?

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#11
In reply to #10

Re: Welding Work Effecting Skid Cable

07/15/2011 5:43 AM

Before any other CR4 user gets tired of this and goes off in a huff (some are susceptible), the reason that the cable fried is overcurrent. It was unable to take the return current to the welding transformer. Whoever did the welding did not connect a local welding current return wire to the skid in question and the only other available path between the job and the welding transformer was the said instrument cable, i.e. that has been damaged.

It's as simple as that.

No amount of further analysis, debate, hypothesising, philosophising, ranting, raving, blogging, unblogging, texting, untexting, e-mailing, reporting, guessing or anything else for that matter will change the fact that the cable is now knackered as a result of its inappropriate use as a welding current return conductor, a job it was seemingly and rightly not designed for and not sufficiently sized to carry out, and must now be replaced.

<unsubscribes and runs off to Del's for a cuppa>

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#12

Re: Welding Work Effecting Skid Cable

07/15/2011 6:46 AM

One other thing to check is the connection of the welding cables at the power supply(s). We have a large welding shop and I have seen on a number of occasions that if the welding lead becomes bent in against the case of the power supply that hooks on over head cranes, etc. would become live and contact with a conductor that is grounded to the power supply will cause a current flow. This could result in a high current flow through the ground wire in your lead. Worth checking! lwc

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#13

Re: Welding Work Effecting Skid Cable

07/15/2011 8:26 AM

Happens all the time, even in the shop on welding tables when the welding ground is left attached to something other than the working surface. In this shop, we replace welding turn tables and 120VAC receptacle ground circuits three or four times per year because of this. No welding ground - the welding current will find one somewhere. In our case, it is most often the ground on the 120VAC into the motorized welding turn tables.

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#14

Re: Welding Work Effecting Skid Cable

07/15/2011 2:44 PM

Thank you for the positive answer, this is my first time facing and heard this kind of problem.
We will replace the cable and no issue for it. Hope the cable inside the conduit is not affected.

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