EFM-100 Atmospheric Electric Field Monitor Electric Field Mill with Monitoring Software

Boltek EFM-100 Electric Field Monitor

Measuring the static electric field generated by thunderclouds the Boltek EFM-100 not only detects nearby lightning but can detect the atmospheric conditions which precede lightning. Electric field data is displayed and graphed on your desktop computer using the included software. 

For complete electrical isolation from the field mill outside, the EFM-100 connects to your computer using a fiber optic cable. The EFM-100 features aluminum and stainless steel construction for corrosion resistance, gold plated connectors throughout, and the highest quality ball-bearing brushless dc motor for excellent reliability.

• Detect lightning up to 24 miles (38 km) away.
• Detect the high electric field conditions which precede lightning.
• Short-range detector is optimized for close lightning to provide the best distance accuracy while ignoring far away lightning.
• Monitor the electric charge above and near your location.
• Monitor up to four separate locations per PC.
• Watch trends develop.
• Attention getting alarms.
• Review archived data from previous storms.
• Stay current with free software updates from the Boltek website.

Electric fields develop wherever there is a difference in electric potential. If the electric field gets high enough you can feel your hair stand on end (if this happens outdoors during a thunderstorm crouch down with your feet together as you are about to be struck by lightning.)  An electric field is what attracts your hair to a charged comb or a charged balloon.

Electric field is measured in Volts per meter (3.3 feet) The electric fields which accompany thunderstorms normally measure in the thousands of Volts per meter, usually abbreviated to kV/m.

The EFM-100 software has three built-in alarms: High Field, Very High Field, and a Lightning alarm. Both the the High Field and Very High Field alarms activate if the electric field magnitude rises above a preset level (user configurable). For example: 1 kV/m for High Field alarm and 5 kV/m for the Very High Field alarm.

The display turns red when the Very High Field alarm is active.

The display turns yellow when the High Field Alarm is active.

Once the field returns to normal the display will return to green.

The Lightning Alarm is activated if a sudden electric field change is detected. Distance is indicated in the distance target. Target distances are fully configurable between 3 to 24 miles or 5 to 38 km. Lightning distances and alarm statuses are announced over your computer speakers.

Up to four field mills can be monitored. The field mills can be connected to the computer directly (fiber optic cable to USB/RS232) or remotely over a network (intranet or internet)