Signal Isolation: What it is and Why it’s Important – Whitepaper

Why do we need signal isolation?

Acromag is in the business of signal conditioning. We manufacture circuits that amplify, isolate, filter, and convert one signal form to another. Most of these circuits also provide electrical isolation. However, added isolation has a cost. Thus, sometimes customers either question their need for isolation or fail to recognize the need for adding it altogether. The white paper below covers the basic aspects of electrical isolation; what it does for you, why you need it, and how we test for it.

In brief, electric current refers to the conceptual flow of atomic particles or electrons through wires and electrical devices. Conductive materials like metal and water allow electric current to easily pass through them. The force that drives electric current to flow through a conductive medium is potential difference or voltage. The opposing force that curbs or limits this current flow is resistance.

Because it is comprised of 60% water, the human body is an excellent conductor. The problem is, if an electric current from a source is allowed to pass through the body, it can induce injury via electric shock. Materials that are weak conductors of electricity have a high resistance to current flow and are often used to add isolation or insulate circuits. Generally, greater force along a conductive path will drive higher current flow.  Poorly controlled flow in the absence of resistance (insulation or isolation), could result in circuit damage, personal injury, or even death.

More About Signal Isolation

There are two principal reasons for introducing signal isolation into an electric circuit:

  1. To block the transfer of high or hazardous voltages
  2. To break ground loops

Download the white paper below to gain a better understanding of the important role that isolation plays in signal transmission. Use isolator products to: protect personnel and equipment from electric shock, enable measurement with high common mode voltage present, block the transmission of noise and interference, and prevent the formation of earth ground loops when linking circuits together. It is the isolation between circuits that allows you to operate each circuit at different ground potentials without creating a problem, as long as you keep the potential difference inside the limits of the isolation rating.


Signal Isolation and Why it's Important: Whitepaper

Related Products & Information

4-20mA Signal Isolators: Acromag offers the industry’s best selection of isolators. Dozens of models are available to meet your requirements. Select from single, dual, and quad-channel models with AC, DC, or loop-powered operation. Signal splitters deliver dual outputs from a single source. And whether you need a unit that sinks or sources current, Acromag has the right solution for you.

Click here to see a related video: How to Prevent Ground Loops with 4-20mA Isolators and subscribe to Acromag’s Youtube channel.