Wiring a Chinese Power supply

[Aussienitro]

I was provided instructions, however like a lot of chinese things they were not for the specific supply I was provided.

Before I go trying to power this thing up I need to know what "FG" is? I'm assuming its a type of ground, however theres also a grond symbol on the case which is aready connected. What do I do with "FG"?

 

[Toke]

It looks like a regular ground connection for the ground wire in a supply cable.

Your supply cable does not appear to have a ground wire, so you need some other way to ground the cabinet. Does the case grounding wire shown connect to anything?

Does power outlets in your country come with a ground connection?
It they do get a 3-wire cable and connect the ground to the FG.

 

[Aussienitro]

Hi Toke,

The wires you see connected did not come with the supply I just pulled the cable out of a microwave. The yellow/green wire is the ground and the other two the AC. So as you can see the microwave cable was grounded to the case which ois what I did here as well as it had the ground symbol. So I've got two grounds and one wire? do I just split the ground wire and connect it to both the case and "FG"?

 

[Toke]

This sounds fine, you have the supply grounded through the supply cable and are good to go.

It makes no difference whether the ground wire is on the case or in the cable connector. The ground connector is usually run strait to case on the inside.

 

[Cyparagon]

Is that for a 40W tube?

 

[Aussienitro]

Thanks, still need a water pump before I can think of turning it on but that's one problem solved. It's for a 60W tube.

 

[Hemlock_Mike]

Try using an Ohm meter to check FG to case ground. I bet it is the same.
If not -- WTH?

HMike

 

[Toke]

I am getting a little nervous on your behalf.
If you are not familiar with electricity, a 60W CO2 laser sounds like the wrong thing to start with. It does after all involve rather high voltage, lethal voltage.

 

[Aussienitro]

Lethal voltages and water! But Yeh you'd be more nervous if you saw the power supply I tried go make from a microwave, talk about overkill, before deciding its safer and cheaper to just buy one.

Yes you are all correct, 0 ohms. Logic wins again

 

[LSRFAQ]

Lethal voltages and water! But Yeh you'd be more nervous if you saw the power supply I tried go make from a microwave, talk about overkill, before deciding its safer and cheaper to just buy one.

Yes you are all correct, 0 ohms. Logic wins again

You already know this because of your ohm meter, but "FG" is a copy of a European marking meaning "FRAME GROUND". It grounds the case of the power supply. AKA safety ground in the US. I have however found some interesting voltages and currents flowing in "FG" leads of "quality import" PSUs so be careful what you connect it to.

Steve

 

[Things]

Yeah FG is just frame ground, it should connect to the PCB and run to a screw in the PCB which holds it into the case. Always check the resistance between FG and the actual frame, just to make sure.

 

[Aussienitro]

Moving on to the other plugs, again the instructions are not specific to this machine.

So it has TH/TL/WP/G/IN/5V, what can I do with this? Only interested in analogue controls.

Can I add a variable resister between two of those terminals to vary the power output? If so what value resister?

Would WP by any chance mean water pump? If so how can one control or power the pump from this?

Can the laser itself be turned on and off via these terminals?

 

[DashApple]

Hi

Yes you can turn the laser on and off ,

TH - TTL High = +5 volts will turn psu on , 0v = Off
TL - TTL Low = Connecting this to ground will turn the laser on ,
WP - Water Pump = has to be connected to ground the enable power supply ( interlock)
G - Ground
IN - Signal In ,
5V - 5 volts DC

For anolouge , You need the WP pin shorted to ground , Then With a 10k Potentiomiter , Connect Pin 1 To 5 v , The wiper ( center pin ) goes to IN , And 3rd pin Goes to the G pin , Then to turn the psu on and off Use the 5V pin and connect to the TTL High Pin ,

This is for stand alone Running / power control .

I am Basing this Info round the Co2 laser psu i have ( 60 watt moddle ) SO it "should" be correct .

Goog luck

Ion

 

[Aussienitro]

Thanks Ion, great help. I would have never figured that out myself.

Still confused about the WP pin what does it do regarding the actual pump?

Off topic, is that CuO/Al thermite in your avatar pic? if so does a 60W CO2 initiate it?

 

[Toke]

The WP does not do anything towards the pump.
It is an input signal from the pump controller to the laser power supply.

The idea is that you should not be able to turn the laser on without having cooling water activated.

 

[DashApple]

The WP is a interlock , it used to make sure the pump / cooling is running befor the laser is Run , But to Bypass it just connect it to ground ( at ur own risk ) .

And yeah Its CuO/Al thermite , No idea havent tryed , I use fuse To set it off .