Why Your Radar Level Transmitter Gave False Readings for Months

Ever had a radar level transmitter that passed calibration in the morning but failed by afternoon? We traced the issue to a $75,000 inventory loss. Our bubbler system showed half full, but actual levels were near empty. The discrepancy cost us countless hours and product.

First, we discovered the root cause: radar waves reflect off liquid surfaces, but certain tank conditions can distort readings. For example, foam, vapor, or internal structures can scatter the signal. However, we assumed our non-contact level sensor was immune. That assumption was wrong.

Then, we investigated further. After pulling rags from dip tape sensors multiple times, we logged data showing the bubbler system consistently underreported. Therefore, we needed a solution that could measure through tank roofs without process penetration.

As a result, we installed the DR6421 Radar Level Transmitter. This through tank radar level gauge uses advanced algorithms to filter out interference. Also, it has no moving parts, so maintenance is minimal. Within hours, it showed 98% accuracy across all levels and temperatures.

Finally, we rebalanced inventory and avoided further losses. The DR6421 is immune to temperature and pressure variations, making it suitable for corrosive and high-temperature liquids. Plus, it offers 4-20mA or RS485 output options for easy integration.

For more on radar level measurement principles, see [this ISA article](https://www.isa.org). How would you solve a similar challenge in your facility?

Tags: #leveltransmitter #DR6421