Envco – Environmental Equipment

The WATERLOG® H-3521 is a digital pressure transducer specifically designed for water level monitoring. The H-3521 directly measures water or other fluid pressure over a broad temperature range. Typical applications include monitoring snow pillows to measure snow pack, measurement of water in accumulating rain gauges, and fluid pressure in weirs and dams. The H-3521 can be used in a gas-purge bubbler installation however other instruments exist specifically for that application.

Key Features
•Directly measure water, glycol or fluid pressure
•Works with rain gauges, snow pillows, artesian wells, piezometers and water tanks
•Ideal for industrial applications such as monitoring culinary water pressure.
•Pressure accuracy is 0.05% full scale
•Accuracy over temperature range exceeds ±0.02 ft. of water
•Built-in temperature compensation
•Operating temperature range -30 to +60 C
•SDI-12 output provides measurement data in engineering units such as feet or meters
•Industrial outputs: 4-20mA and Modbus RTU
•Enclosure is nonconductive and corrosion proof
•Low current operation (150µA standby)

The H-3521 has RS-232, SDI-12 and Modbus “smart” digital interfaces together with a 4-20mA analog output. The sensor makes multiple pressure measurements, averages the results and converts the measurement data into units of PSI, Feet, Meters or other engineering units. The H-3521 is easy to use and works with any SDI-12 data recorder. The “Serial-Digital Interface” is ideal for data logging applications with the following requirements.

• Battery powered operation with minimal current drain
• Pressure measurement data is transmitted digitally over long cable lengths without error
• Multiple sensors on a simple three-wire cable
• Up to 250 feet of cable between a sensor and the data recorder
(Use of H-423, SDI-12 to RS485 converter extends the range to 1000's of feet)
(H-4500 fiberoptic media converter works up to 1.2 miles)

Extended SDI-12 command for setting the Stage to the current water elevation or pressure

Ordering Information
Please specify H-3521-15 for 15 PSI, H-3521-30 for 30 PSI, or H-3521-XX for 50 PSI
H-3521 Non-Submersible Pressure Transducer. Compatible with wet media. SDI-12, 4-20mA and MODBUS outputs
Media must be compatible with Stainless Steel