Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [isolation]

Allowing for the flow of power or information without shared electrical nodes

Electrical isolation (also called galvanic isolation) can be achieved by transforming electrical energy into another form. These include magnetic fields (transformers), light (optocouplers and fiber-optics), mechanical (shaft-coupled motors), and vibrational (speakers/microphones).

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Are there any disadvantages using magnetic couplers instead of opto-couplers?

I'm trying to find the disadvantages of using magnetic couplers versus opto couplers (1). I'm deciding which of the two I should use to create a galvanic isolation between two PCB's that are going to communicate via SPI in a normal environment e.g…
Nick
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Protecting two layers of PCB with electric tape?

I have soldered several small PCBs, and I want to stack them together (using hex spacers). However, since lack of (vertical) space it could be that some components (on the top) might touch the wires/solder junctions (on the bottom) of the PCB…
Michel Keijzers
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Electrical Isolation

I've been reading about the EIA-485 standard and they talk about how even with twisted pair wire they need a 3rd connection for common because sometimes the devices need to be isolated. I was thinking about it and I've always taken isolation for…
NickHalden
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Does this circuit have proper isolation?

I have a development board from Microchip. It works on 12 V DC. The input pins can only work on 3.3 V so what I have done is I have designed a circuit using a PC817 optocoupler. So on the LED side I am supplying 12 V and on the transistor side I am…
S Andrew
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I2C isolation; 3kV

I am working on a high-side current sensor, where the high-side is around 3kV. I have come to the conclusion, with some help from you kind folks, that it is best that I float the majority of my circuit up at that 3kV level. However, I need to get…
John
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Isolation between measuring voltage from low current circuit?

simulate this circuit – Schematic created using CircuitLab I have a low current current circuit and I would like to be able to measure the voltage on one point of the circuit but have electrical isolation between the low current circuit and the…
anna
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Separating / Isolating the circuit blocks

I was designing the circuit of a superhet receiver, block by block. Needless to say, my concern is how would I separate the various blocks. In other words, how would I interconnect the blocks ( not just this circuit, but any circuit) so that one…
Plutonium smuggler
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Isolation for loop powered devices with limited power

I am implementing 4~20mA Transmitter that consist of a MCU, a current DAC, and an ADC for measuring an analog signal. I would like to electrically isolate the analog signal from the loop current so that the higher end control system (i.e master…
Steve
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Isolated electronics for industrial application

I'm designing some boards for an industrial application. Basically, these are boards that verify the correct functioning of some power supplies (they measure the output voltage and check some POK signal and report the status via a message on the…
Federico Massimi
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Is it safe to attach external sensors to this mains powered ESP smart socket?

I have read up a lot that generally it is unsafe to attach anything to these IoT devices that operate from mains power. As the power supply is not isolated and you are risking to get shocked with the large power potential. I was looking at devices…
somerandomusername
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Purpose of galvanic isolation with one power supply

I searched the forum for similar threads and didn't find the right answer. Why should I use galvanic isolation in a system that contains only one power supply (a battery)? I don't have the right argument to convince my co-worker that using isolators…
giusepe
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Preventing shock risk on isolated transformer secondary circuit

I fully understand that you cannot get a shock from either phase1 or phase 2 on the secondary of the isolated transformer, however you can be shocked by touching both. My question is how do you provide protection on a boat whereby the earth wire is…
Peter Gillham
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What can be the reason multi-meter shows continuity even though there is isolation?

I'm dealing with a module where the block diagram is given as follows: The datasheet can be found both at here and an alternative one here. When I perform a continuity test with a multi-meter between I/O Common and the Power Common pins, there is…
user1245
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Isolation Amplifier? Reading differential voltage on 600 V lines

I need to measure the voltage across the leads of a thermocouple, the thermocouple being physically connected to a 600 Vdc terminal. The instrument which measures the thermal couple (thermometer) will not withstand a 600 Vdc input. How can I read…
A.S.
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Lifted ground in serial communication?

I have a battery, where the negative terminal is being switched by an NMOS circuit. I also have a solar charge controller, which is controlled by serial interface. The serial interface requires common ground. A microcontroller is connected directly…
user95482301
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