The use of isolators in fire security applications originated in the 1990s. In the Netherlands in particular, their adoption grew rapidly, partly due to local regulations that allowed the use of a ring circuit combined with isolators as a fully approved alternative to fire-resistant cabling.
This marked the end of the need for expensive and rigid function-retaining cables — a clear step forward in both cost efficiency and ease of installation.
Today, the ring circuit has become the standard in almost every fire and security system. This approach has led to systems that are not only more efficient but, above all, more reliable.
Breakthrough in Voice Alarm Systems
While ring circuits had long been common in fire detection systems, their use in voice alarm evacuation systems took longer to develop.
In 2008, the Dutch company TMCDAS (formerly Taxameter Centrale) became the first to introduce a practical and reliable solution specifically designed for this type of application.
This was a significant technical challenge.
Unlike conventional fire detection systems — which typically use low-power components (maximum 1A at 24VDC) — voice alarm systems operate over a combined transmission path, consisting of:
This dual-signal structure places high demands on both the electronic design and component selection of the isolator.
Over the years, various manufacturers have attempted to create similar solutions, but not all achieved the desired performance. Some poorly designed products even contributed to a negative reputation for isolators in these applications.
Durable and Proven Design
From the very beginning, TMCDAS opted for high-quality components and a robust design philosophy.
The introduction of our IS8200-1 isolator in 2008 proved to be a major success. Since then, over 130,000 units have been produced, with a failure rate that is virtually negligible.
Moreover, many of our earliest installations continue to operate flawlessly — even after 15 years of continuous use.
This not only demonstrates the reliability of our design but also reflects our commitment to quality and innovation.
