This white paper describes how to select the proper hardware for high resolution current monitoring with PMI Recorders. Most of PMI’s recorders offer the ability to measure current via user selectable iron core TLAR clamps or Flexible CT’s. In order to fully understand the differences between these devices, it is necessary to review their specifications. Table 1 outlines the complete specifications of the TLAR (Iron Core Clamps). Included are the specifications for Flex CTs (Flexible, Multi Length Clamps). A review of the specifications of the Flex CTs and TLARs helps to define the possible applications for each type of probe. The main difference between the two is the full scale current range for which each device is rated. The full scale range of the TLAR is 200A; for the Flex CT it is 5000A. This is a huge difference in terms of amperage, but the main difference is in application. Both devices serve the same function, but the TLARs are better suited for data resolution at lower current levels.

This white paper includes:

• Full scale value (also known as A/D counts)
• TLAR specifications
• Gain controller
• Data resolution
• Flex CT specifications
• Low current monitoring
• High current monitoring