ATSI manufactures professional electrical test and measurement instruments for the traffic signal, traffic data collection, and parking industries. Excellent customer support and expert technical assistance are our top priority. Our products have earned a strong reputation for quality and reliability. From innovative product design to service that stand behind our products, ATSI has become the standard for traffic signal test equipment.

ATSI is the industry leader in Conflict Monitor testers, BIU testers, Loop & Detector testers, Surge Suppressor testers, Load Switch/Flasher/Transfer Relay testers, and Counter/Classifier testers. ATSI is also an authorized distributor for the complete line of AEMC® electrical test and measurement instruments. AEMC. is the leader in current measurement probes, ground resistance testers and insulation resistance testers. Their full product line also includes clamp-on meters, ratiometers, power meters, harmonic power meters, data loggers, light meters and numerous other electrical test tools.

All Sales, marketing, and production facilities are housed in a single location in Athens, OH. ATSI products can be purchased through a network of distributors. We also offer custom products on an OEM basis.