Linked Questions

1
vote
3answers
211 views

What are all the reasons that transformers are considered safer? [duplicate]

I am making a circuit for measuring AC mains voltage and current and I want to avoid using a transformer because it introduces distortions. But everyone says that the circuit will be considered unsafe ...
48
votes
6answers
26k views

Why do we need an isolation transformer to connect an oscilloscope?

My professor always insists that I provide power to an oscilloscope thorough an isolation transformer. What is the necessity of this? What is the risk if I don't connect it?
24
votes
5answers
4k views

Help learning from a mistake connecting an oscilloscope

I have built this circuit to dim a lamp with a PWM signal. It had an issue where the MOSFET was getting really hot. So I wanted to know what was happening on the gate of the MOSFET. I turned the PWM ...
4
votes
4answers
8k views

Why does isolation transformer protect from shock?

Perhaps I can best explain the question with two examples: (1) there is PC powered directly from 230V mains (unprotected by RCD or similar), and there is fault in PC that causes line voltage to ...
4
votes
4answers
1k views

What does it mean that a power supply is 'referenced to mains' and why is that dangerous?

I was watching a few different videos by BigClive on youtube. He was mentioning the danger of a particular light chain power supply because it was 'referenced to mains'. The voltage across the output ...
2
votes
2answers
2k views

AC voltage measurement with a microcontroller

I want to build a circuit that will eventually calculate power, power factor and thd for a light switch or a wall outlet. But I'm having some problems with the voltage measurement circuit. simulate ...
1
vote
4answers
819 views

How can I connect more than device on the same Isolation transformer?

Why isolating transformer should be used to protect only one item of equipment at a time? I tried to search and I found this answer, but I could not understand it. This is why, ideally, an ...
0
votes
1answer
244 views

Will get shock from Isolated transformer?

I have read a good discussion about the safety of an isolated transformer. However, in my understanding, the secondary side of the isolated transformer is floating, so will it has a high potential ...
0
votes
2answers
586 views

Oscilloscope ground and unit under test ground issue

I am working with an instrument which has a supply of 230V AC or 400V DC. AC source is isolated at the input via 1:1 transformer and DC source is a floating supply. I have a Yokogowa DL1620 ...
1
vote
1answer
113 views

Safety precautions when developing and testing mains voltage devices [closed]

Specifically, I am planning to design and build an energy meter to measure power drawn from mains - 120V 60Hz. What are the risks associated with developing and testing this device and how to minimize/...
0
votes
2answers
300 views

Oscilloscope measurements on device connected to a AC/DC wall-plug

I had a discussion with my colleges regarding Oscilloscope measurements and DUT (device under test) isolation. Specifically a device connected to a AC/DC wall-plug. I think I am aware of the concepts ...
1
vote
0answers
286 views

Should my external analog input be isolated?

I want to build a device that samples analog signals from various measurement instruments via their analog outputs. The instruments have their own power supply, and all devices are powered from the ...
0
votes
1answer
106 views

What precautions should I take to setup a home electronics lab? (Living in the UK) [closed]

I'm soon to be buying a house in the UK and would like to setup an electronics lab in the garage (attached to the house).The type of equipment I'll be using is nothing out of the ordinary: ...