CR9321-NPN

Current Sensors Overview

The CR9321-NPN is a solid-state AC current switch manufactured by CR Magnetics Inc., designed for non-invasive monitoring of alternating current in electrical systems. It features an NPN output configuration and operates with a single pass-through design, allowing the conductor to pass directly through the sensor core without mounting hardware. The device supports bidirectional current sensing up to 100A. In its off state, it withstands a maximum of 240 VAC RMS, while the on-state continuous current rating is 0.8 AAC RMS. The turn-on time is specified at a maximum of 100 ms at rated conditions, with a minimum holding current of 10 mA required to maintain the switched state.

Current Sensors Feature Summary

• Solid-state construction with NPN output configuration for reliable switching
• Non-mounting solid core design enabling single pass-through installation
• Bidirectional current sensing capability for versatile application integration

Current Sensors Applications

• Electrical system switch control
• Current monitoring in power distribution circuits
• Transformer protection schemes

Current Sensors Procurement Notes

Verify that the specific order matches the NPN output variant, as CR Magnetics offers PNP configurations in the same series. Confirm that the application voltage does not exceed the 240 VAC RMS off-state limit. Ensure the load current remains within the 0.8 AAC RMS continuous rating to prevent damage. Check datasheet specifications for thermal requirements under continuous operation.

Current Sensors Selection Notes

Select this component when a non-invasive, solid-core solution is required for AC current monitoring. The NPN output is suitable for interfacing with standard logic inputs or relay drivers. Consider the 100A sense range against expected load currents. Evaluate the 100 ms turn-on time against system response requirements. Ensure the installation environment supports the operating conditions defined in the official documentation.

Current Sensors Part Context

This part belongs to the CR9321 series of current switches from CR Magnetics Inc., which includes both NPN and PNP output variants. The series is characterized by solid-state technology and non-mounting core designs. The CR9321-NPN specifically provides open-collector style switching via NPN transistors, distinguishing it from the complementary PNP version in terms of output polarity and circuit connection requirements.

Current Sensors Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. When replacing, ensure the new component matches the NPN output type, 100A sense range, and 240 VAC RMS isolation rating. Verify compatibility with existing control logic levels.