What inputs are needed?

Transformer MVA rating, voltage, impedance, and fault data. From these it produces first-pass overcurrent setting checks.

Does it replace manufacturer relay software?

No. It does not replace the relay manufacturer's software or a stamped protection study, and settings must be confirmed against the applicable standards and engineering judgment.

Is this a finished tool?

It is an early prototype tool. Use it for a first pass and confirm all settings independently against standards and engineering judgment.

It is for protection engineers and students working on first-pass transformer overcurrent settings and training.

Transformer Overcurrent Setting Calculator (50T)

This is a transformer overcurrent setting calculator. It helps check overcurrent (50/51) settings for transformer protection using the transformer rating and impedance, with an interactive transformer model. It runs locally in your browser.

Who it is for

Protection engineers and students working on transformer overcurrent settings and training.

Inputs and outputs

Inputs: transformer MVA rating, voltage, impedance, and fault data.
Outputs: overcurrent setting checks for the transformer.

Typical use cases

First-pass transformer overcurrent settings.
Training and learning how transformer overcurrent protection is set.

What it does not do

This is a prototype tool. It does not replace the relay manufacturer's software or a stamped protection study, and all settings must be confirmed against the applicable standards and sound engineering judgment.

Privacy: This tool runs entirely in your browser. The values you enter are processed locally on your computer and are not uploaded to a server.

Related tools

Frequently asked questions

What does this calculator do?: It is a transformer overcurrent setting calculator that helps check overcurrent (50/51) settings for transformer protection using the transformer rating and impedance, with an interactive transformer model.
What inputs are needed?: Transformer MVA rating, voltage, impedance, and fault data. From these it produces first-pass overcurrent setting checks.
Does it replace manufacturer relay software?: No. It does not replace the relay manufacturer's software or a stamped protection study, and settings must be confirmed against the applicable standards and engineering judgment.
Is data uploaded?: No. This tool runs entirely in your browser. The values you enter are processed locally on your computer and are not uploaded to a server.
Is this a finished tool?: It is an early prototype tool. Use it for a first pass and confirm all settings independently against standards and engineering judgment.
Who is it for?: It is for protection engineers and students working on first-pass transformer overcurrent settings and training.