Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

No-load power-saving circuit of AC welding machine.

Status
Not open for further replies.

prabrahim

Newbie level 3
Joined
May 1, 2011
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,298

DeepOne

Advanced Member level 2
Joined
Feb 26, 2011
Messages
632
Helped
99
Reputation
200
Reaction score
98
Trophy points
28
Location
45N39E, Russia
Activity points
0
Hi, Prabrahim
I suppose it is necessary to add 12V integral stabilizer of the voltage after diode bridge and filterring capacitor

C4 must be not electrolytic
 

prabrahim

Newbie level 3
Joined
May 1, 2011
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,298
sir,
i had used a regulator 7812 with 0.1 mfd on both input and output of the regulator
 
Last edited:

DeepOne

Advanced Member level 2
Joined
Feb 26, 2011
Messages
632
Helped
99
Reputation
200
Reaction score
98
Trophy points
28
Location
45N39E, Russia
Activity points
0
well, then it is necessary to take in hands tester and measure the state of working component.

may be 12V zener not really 12V.
 

BradtheRad

Super Moderator
Staff member
Joined
Apr 1, 2011
Messages
13,975
Helped
2,786
Reputation
5,570
Reaction score
2,693
Trophy points
1,393
Location
Minneapolis, Minnesota, USA
Activity points
104,248
This is a clever circuit and practical as well.

However it puts low-power circuitry in close contact with high power...

In such a case you need to ensure cooperation between the two.

This circuit should be tested in sections. The timer circuit should be tested for proper operation without being hooked up to the welding circuit.

Then take the next step. Wrap a few turns of coil L around the welding cable. Notice that the coil L is not directly connected to the welding cable. It's only wrapped around it.
Wrap just enough turns to result in a usable signal to pins 2 and 6 of the 555 IC.
Do some welding. Stop. See if the machine turns off at the end of the timed delay.

I have doubts about the wire containing switch K2. It connects delicate components to the welding cable. When welding stops, the transformer coil may generate a hi-voltage spike. This may destroy the timer devices. Maybe it happened already.

I suggest adding a resistor in that wire between welding cable and K2. Start with a high ohm. Reduce resistance until you get proper operation.
 
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top