Summary of An Isolated Adjustable Auto transformer using microcontroller
This article describes a safety test setup for AC mains circuits, combining a fused isolation transformer with a variable auto-transformer in a grounded enclosure. This configuration enables safe voltage ramping and direct oscilloscope measurements without the inaccuracies of differential probing.
Parts used in the Isolated Adjustable Auto Transformer:
- Fused isolation transformer
- Variable auto transformer
- Grounded fire safe box
This is a means of testing AC mains operated circuits at variable AC voltages,
and it also provides isolation to allow safe measurements of that circuit.
together in a grounded, fire safe box. What more could you ask?
Find updates at www.projects.cappels.org
Introduction
I need to be able to test and measure the operation of circuits operating directly from the AC mains, this includes being able to slowly raise the voltage while monitoring circuit performance. This was solved with a variable auto transformer and an isolation transformer. Now, I can choose what part of the AC operated circuit to ground, and connect my oscilloscope directly to the relevant part of the circuit; no more using two probes and doing the old Channel 1 – Channel 2 bit, along with its inherent inaccuracies. The variable transformer allows me to slowly increase the voltage to power supplies under test, so that I can back off on the voltage if signs of malfunction appear.
For more detail: An Isolated Adjustable Auto transformer using microcontroller
- What is the primary purpose of this project?
The project tests AC mains operated circuits at variable voltages while providing isolation for safe measurements. - How does this setup improve oscilloscope measurements?
It allows connecting the oscilloscope directly to circuit parts by choosing which part to ground, eliminating the need for two probes. - Can I slowly increase the voltage with this device?
Yes, the variable transformer allows you to slowly raise the voltage to power supplies under test. - What happens if signs of malfunction appear during testing?
You can back off on the voltage immediately using the variable transformer. - Is the equipment housed in a safe enclosure?
Yes, the transformers are connected together in a grounded, fire safe box. - Does this method avoid inherent inaccuracies?
Yes, it avoids the inaccuracies associated with the old Channel 1 minus Channel 2 probe method.
