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Anonymous Poster

40 KVA generator welding machine

02/08/2008 12:53 PM

welding machine contain a 40KVA generator three phase used as welding machine we use a full bridge 3-phase rectifier then a thyristor to control the output power I need for trigger circuit for thyristor please. send your reply directly to my e-email muh_sabri1967@yahoo.com
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North of 60
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#1

Re: 40 KVA generator welding machine

02/08/2008 1:06 PM

Ok... that will be sent right along. In case you don't grasp my meaning, its known as "sarcasm".

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MUKULMAHANT
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#2

Re: 40 KVA generator welding machine

02/09/2008 12:56 AM
  1. What is DC Voltage before you(want to) Control to Welding Current?
  2. OR Do you want a system 3Ø firing angle control to get reqired welding Amps?
  3. OR Do you want to buy a new professionally -completely -built Welding machine which will take AC 3 Phase 415V?? in from your Genset?
  4. You want a modern,light inverter welder. Or a classic Hefty-rated 500Amps 100% time cycle duty 415v 2 wire input welder. Or a most-modern 3 wire 3 phase in IGBT inverter Continuous rated MIG 630 Ampos machine? To do 3mm sheeting to 32mm shipbuilding plate work in tandem welds?

You will be best off with#3

I can sell you brand new powerful Welding machine/s to run off your 40KVA GEnset.

What is that you want to weld--how often -thicknesses/materials-please spell out.

I really can help you .

Where are you located.

BEST

mm
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Anonymous Poster
#7
In reply to #2

Re: 40 KVA generator welding machine

02/09/2008 11:41 AM

Dear Sir ;

Thank you for replay , I'd like to rectify the o/p of generator with out smoothing so that give me ability to change the o/p voltage (without fall in SCR latch) , now I'll answer you about your questions:

  1. The peak Voltage of DC non smoothing voltage is 60 Volt.
  2. yea I want that but( hopping understand my idea above).
  3. No I've 50 Volt phase to phase.
  4. No

Send me please on my e-mail

muh_sabri1967@yahoo.com

I'm Iraqi and work in Sudan

thank you
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leskranes
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#3

Re: 40 KVA generator welding machine

02/09/2008 8:18 AM

Most economical is to locate a large enough 3 phase machine & connect through appropriate size fused disconnect switch. I have a 15 kw gen set that I use in this manner with good results. I can also change out the CC (constant current) power supply to a CV (constant voltage) power supply for MIG welding or even connect a TIG. I also use a step-down transformer for supplying lighting & power tool 120 VAC.

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Anonymous Poster
#5
In reply to #3

Re: 40 KVA generator welding machine

02/09/2008 10:31 AM

Dear Sir;

thank you for response could send me the schematic of wire connection even not standard, I'd like to use my generator as welding machine multiple output voltage.please for more information you need call me on my e-mail

muh_sabri1967@yahoo.com

thanks a lot
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marcot
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#4

Re: 40 KVA generator welding machine

02/09/2008 9:18 AM

It could be done simply with a switch, a capacitor , a few resistors, and a zener diode. An electronics technician is also needed...

Do you realize that by switching the DC side with the thyristor, you will be able to turn it ON but will not be able to turn it OFF with the switch. The thyristor will latch on and will only turn off when the current will be interrupted by lifting the electrode.

If you want full control, you need to use thyristors as AC rectifiers which is much more complicated to the point that you should buy something that already works.

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Anonymous Poster
#6
In reply to #4

Re: 40 KVA generator welding machine

02/09/2008 10:41 AM

dear Sir;

in not smoothing output DC rectifier we can OFF and ON the thyristor cause the rectified wave is reach the zero volt (OFF SCR) I was tray it early so I need for perfect triggering cct.tthat give me multiple output voltage.

thanks a lot
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marcot
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#8
In reply to #6

Re: 40 KVA generator welding machine

02/10/2008 9:07 AM

Welding machines are highly inductive voltage/current sources. As such, once the current is established in the circuit, it doesn't follow the voltage ripple (the time constant is too long). The current is much more affected by the arc that the DC ripple. This means that the thyristor is not going to turn off at the zero crossing of the line voltage. By the way, after a three phase bridge rectifier, the DC voltage does not return to zero like a single phase application. This will keep the thyristor latched until you open the circuit by lifting the electrode.

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Anonymous Poster (3); leskranes (1); marcot (2); MUKULMAHANT (1); North of 60 (1)

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