Am I working safely?

[Francesc V.]

Hi:

I would like to ask you a couple of questions regarding my work station.

1. Is this a right isolation transformer to isolate it from ground and work more safer for instance with SMPS?



I bought this transformer where I have plugged a serial lamp and from it I plug the PCBs I want to test.


2. Isolating correctly the oscilloscope

I am not sure if connecting the oscilloscope at the isolation transformer will be good idea when measuring things with HOT GROUND........or maybe better to use batteries and have it fully isolated.
I'v bought a second hand osciloscope and I have built a 5V battery for it.......is it a good configuration? or both are good?



Thanks in advance,
Francesc.

[R_J]

Re: Am I working safely?

That is NOT an isolation transformer, it is a variac (autotransformer) It will not isolate anything from the a/c line.

[Francesc V.]

Re: Am I working safely?

Thanks R_J for highlighting it!!...
So better I buy a real isolate one before I die.

What about the oscilloscope external supply? Battery powered is a good isolation from ground, right?

[harp]

Re: Am I working safely?

Just dont even think that isolation transformer is ultimate safety against dieing or worse...
Have you watch and understand plenty of yt videos about problem with ground and where come isolation transformer handy?

Battery power devices is more protected in practice, when using only one channel.

[stj]

Re: Am I working safely?

real men just keep their hands dry and watch where they put their fingers

i couldnt count the number of times i disconnected a 20kV charged crt with bare hands

[R_J]

Re: Am I working safely?

The isolation transformer is there to protect the equipment and the unit you are working on, It is not going to protect YOU from getting shocked or worse.

It is necessary when connecting a line powered scope to a smps primary circuit. without an isolation transformer, as soon as you connect the scope ground to the primary hot ground you will blow the primary circuit and likely your scope ground clip and lead at a minimum.

[harp]

Re: Am I working safely?

real men just keep their hands dry and watch where they put their fingers

i couldnt count the number of times i disconnected a 20kV charged crt with bare hands

NHF, newermined how much smileys you put, that comment is not helpful in this type of thread...

[stj]

Re: Am I working safely?

[Francesc V.]

Re: Am I working safely?

Do not worry.......I think I am getting the irony. Thank you all for your replies.

I got a Real isolation transformer (1000 VA). However I put 230V on the input and I only have 180V on the output. I am wondering whether to use it or not. The idea goes as follow:

I connect the transformer to the main. The output for this transformer to the VARIAC and setting it to 230V. The VARIAC's output to the serial lamp.......

Will it be ok or better I keep the current config?

Thanks you your patience of keeping me alive

Regards,
Francesc.

[petehall347]

Re: Am I working safely?

isolation transformer should be 1 to 1 so something is wrong .

[stj]

Re: Am I working safely?

got a picture of it?

[Francesc V.]

Re: Am I working safely?





2-4 1 ohm
3-5 1 ohm
( I also tried to feed 230 in both "inductances" at same time; same result)

I am getting about 180V between 8-11 in the secondary.

[harp]

Re: Am I working safely?

Thats a nice one

You are doing something wrong with wiring.

I guess that in primar is two 230 windings, first between pin #2 and #3, and second between pin #4 and #5.

Secondary might be between pin #9 and #10

Check double before plug in...

[petehall347]

Re: Am I working safely?

its wired wrong .. looks like it needs the jumpers .
looks more obvious here ..

[harp]

Re: Am I working safely?

Yes... external jumper settings (connection link) may represent this ilustration indeed, but how he get 180v?

[Francesc V.]

Re: Am I working safely?

Fixed!! I was missing 3 jumpers.

2-3,4-5,9-10

So.....I will use it instead of the VaRIAC.

Badcaps approved??

[petehall347]

Re: Am I working safely?

Fixed!! I was missing 3 jumpers.

2-3,4-5,9-10

So.....I will use it instead of the VaRIAC.

Badcaps approved??

well done .

[Per Hansson]

Re: Am I working safely?

Badcaps approved??

No! I have to say that is the most counter intuitive transformer plate description I have ever seen, and I have seen some confusing crap!
Good work getting it working without it blowing up!

[Francesc V.]

Re: Am I working safely?

No! I have to say that is the most counter intuitive transformer plate description I have ever seen, and I have seen some confusing crap!
Good work getting it working without it blowing up!

All tests done using the light bulb......that helped not blowing up everything. Once mounted I realise that there is a YouTube video that explains all steps.

[sam_sam_sam]

Re: Am I working safely?

No! I have to say that is the most counter intuitive transformer plate description I have ever seen, and I have seen some confusing crap!
Good work getting it working without it blowing up!

I have to agree with you on this most of the time it would show you what terminals would give you a certain voltage this one shows you the windings real odd