Use this tool to calculate the expected resistance of your loop circuits based on the length and type of wire installed.

The resistance of each loop circuit should always be tested on site following installation and if not within reasonable tolerance of the expected resistance further investigation is recommended to ensure there are no faults in the wiring.

High resistance can cause the loop driver to display an error, or it may result in clipping or power limiting.

Most Ampetronic hearing loop drivers have a minimum resistance limit between 0.2 Ω and 0.5 Ω, documented in the relevant product handbooks.

You can also use this calculator to ensure you have the right length and wire gauge to meet that threshold before installation.

For best results we recommend specifying your system using Loopworks Design, or contacting Ampetronic for advice.

Please note that this calculation used in this tool is based on the resistivity of annealed copper at 20°C and should be used as a guideline only. Small differences are to be expected dependant on the exact cable specifications and ambient temperature.

Flat copper tape

Ampetronic flat copper tape (cable) is the default choice when installing loop cable under floor coverings such as carpet, wood, laminate, tiles or linoleum. The cable will not be visible under most floor coverings and is generally secured to the floor with Printed Warning Tape that alerts tradespeople, such as carpet fitters to its presence.

Direct burial cables

DBC Direct Burial Cable for hearing loops from Ampetronic for laying in concrete screed, immune to the corrosive effects of concrete.

This specialised EPR-CSP HOFR (Heat and Oil Resistant, Flame Retardant) cable offers more durable insulation and improves protection where a loop wire needs to be installed in a concrete screed.

We offer free advice and guidance to all of our customers on any subject related to induction loops and assistive listening systems.

Our information centre also contains a great deal of useful material. If the website does not answer your questions please contact us by phone, email or talk to us through Live Chat.

We will endeavour to respond to any enquiry within 1 working day.

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