Non-Contact Voltage/Magnetic Field Tester less than gt/ greater than 5mT Frequency Range (Hz) 50 to 60 Hz Control Circuits Determine The Presence of Magnetic Fields (AC/DC/Permanent) Dual AC Voltage Ranges 24 to 1000V and 90 to 1000V with High Sensitivity That Allows It to Detect Low Voltage AC Wiring Commonly Found In Doorbell Circuits I Cat IV 1000V Safety Category Meets Cetlus and CE Thermostats Video Surveillance Camera Power