This machine blew my clamp meter up.

[martinxxxxxx]

Hi All

I was called to a printing company to look at a 3phase seam welding machine as users were reporting getting shocks from it.

I has a 4mm earth bond to the movable seam section, but no bond on the main table.

So I decided to take a 10mm bond from the connection box on the wall and measure the voltage between it and the metalwork of the machine.

I connected black crock clip to 10mm cable going back to the wall mounted isolator switch earth bonding point and the the red clip to the exposed metal work of the machine.

When the machine was used to make a weld. My connected meter went up in smoke after lighting up like firework.

The machine is a

Digicon Micro Systems Seam welding machine for welding fabrics.

I have lock off the machine and said it is not safe to use.

Any ide

 

[Andy™]

what were you using to measure voltage? did you have it on correct setting?

never seen one of those machine before, so no idea how it works

 

[kme]

1st thing you need to do is verify integrity of earth connection to local isolator / connection. i.e. Zs

IF that is ok....

Disconnect & do insul. tests - it sounds like a bad earth, combined with (maybe) decoupling capacitor failure (Sidewinder or Canoey are likely to know that side of it better than me).

KME

 

[Sidewinder]

martin,

Your thread title reads clamp meter, yet you mention connecting leads, you don't connect any leads with a clamp meter!

I think we need to work a little on this with ideas going back and forth as I don't see what you are attempting to do.

Do you have a link to the exact machine details on the web please?

Is it an HF type machine, what fabric is being welded?

Are they getting a "tingle" or a sharp but small "belt" as these could be different issues.

What is the "welding" process?

 

[kme]

Ah, but you *can* use leads on a clamp meter....to measure voltage.

If the O/P series`d a clamp meter with the earth cable & bed of machine, he should have read volts p.d. between them......unless the clamp meter was set on ohms ...!

Martin. This is one of the reasons for ensuring you use the correct meter ( and settings) for the test.

What make / model is / was the clamp meter? How did you have it set? What were you trying to test?

? A leaky tx on the welding system might put a voltage on the body of the machine?

 

[Sidewinder]

^ On some KME, I have one that is a current clamp only, damn good one too!

You have yet to meet it, and it is not new!

 

[martinxxxxxx]

Voltage measurement with probes on ac volt setting. 600VAC range

It is for sign vynal welding and it is HF.

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I did carry out IR measurement on machine, but obviously it was ins quiecent condition at that time and therefore tx may not have been connected. Anyone want to come and fix it?

 

[Sidewinder]

OK, so you were not using the clamp section, this makes more sense.

HF welding of pvc signs helps also.

Thanks.

Any news on a link to the machine info yet please?

Tingle or jolt type shock?

---------- Post Auto-Merged at 19:10 ---------- Previous post was made at 19:10 ----------

I'll come and sort it no problem!

 

[Sidewinder]

Get on with it then, you have my number if you need help! :slap

 

[kme]

I need the work - I`ll go !

I know......... FIGHT for it!

or.......`cos its a complex problem; it may need the combined knowledges of the three of us.................

So we`ll all go - soddin` expensive repair, but we`ll have fixed it, or it won`t be fixable (unlikely) opcorn

 

[martinxxxxxx]

This is the machine, anyone able to fix them

Digicon presents High Frequency PVC Welders

---------- Post Auto-Merged at 21:46 ---------- Previous post was made at 21:42 ----------

It is a FAB-003

 

[Sidewinder]

Yes a few of us I suspect!

I'll check the link now.

 

[martinxxxxxx]

This is the machine, anyone able to fix themDigicon presents High Frequency PVC Welders

---------- Post Auto-Merged at 21:46 ---------- Previous post was made at 21:42 ----------

It is a FAB-003

Model number

 

[Sidewinder]

Checked the link have the MD's name & phone no, still yes!

---------- Post Auto-Merged at 21:58 ---------- Previous post was made at 21:53 ----------

I'll also be cheaper than getting someone over from the HQ in India!

 

[martinxxxxxx]

This is a RF welder with a serious fault, without any disrespect to you but have you any experience fixing machines welding at around 30MHz?

I don't think the client is going to want to pay if it does not get fixed. If you want to come and make an assessment you are welcome to do so. But you won't get

 

[Sidewinder]

No problem Martin, I can fix it.

I have tons of machinery experience from apprentice through service, to design and applications engineering working with sole traders in their support through to being employed by global blue chip companies both machinery and control systems equipment manufacturers.

My Bachelors & Masters of Engineering degrees are sort of "Mechatronics" a mix of mechanical, electrical and electronic engineering.

 

[martinxxxxxx]

Any RF experience?

 

[Sidewinder]

RF as far as comms mob phones etc. little, but HF pvc welders yes, different makes though.

 

[ProDave]

It sounds to me like the full HF welding current went through your meter.

I still don't understand why that blew it up, assuming the meter was set to ac volts.

But earth bonding throughout the whole machine needs looking at.

 

[martinxxxxxx]

It sounds to me like the full HF welding current went through your meter.I still don't understand why that blew it up, assuming the meter was set to ac volts.

But earth bonding throughout the whole machine needs looking at.

The bloke who came to look at it agrees with you (about the full weld current passing through the machine and the bonding), he said there is stray RF everywhere and has given me alist of bonding tasks to do. He says being an indian built machine there are a lot of improvements that can be done.

Of course it was on AC volts, my neon two wire voltage indicator went the same way too