SU-221 Ultraviolet (UV) Sensor

Ultraviolet (UV) Sensor

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Measure total radiation from 300 to 400 nm

If you need easy, accurate, affordable UV-A radiation measurements in outdoor environments, horticulture operations, and lab settings, we’ve got you covered. The low-cost SU-221 Ultraviolet (UV) Sensor is a scientific-grade sensor that provides the accuracy you need for less. And that’s not even the best part. We’ve made it plug-and-play with the ZENTRA system, so you can access remote data in real-time, wherever you are.

Use it absolutely everywhere

The Apogee SU-221 digital UV sensor has traceable calibration for accuracy you can trust. It’s conveniently small and lightweight, so you can put it almost anywhere. And it’s sensitive to a wide spectral range, 300 to 400 nm, which spans the solar UV range and UV output range of electric lamps.

Simple, self-cleaning, and tough

To save you time, this rugged UV sensor is engineered to be seriously low maintenance. It has a tough anodized aluminum body with fully-potted electronics. The patented domed-shaped sensor head facilitates runoff of dew and rain, keeping the detector clean and minimizing errors caused by dust blocking the radiation path.

Stands the test of time

All Apogee UV sensors come with a marine-grade stainless-steel cable connector that simplifies sensor removal for maintenance and recalibration. The cable is made of shielded-twisted pair wire with a TPR jacket for high water resistance, UV stability, and flexibility in cold conditions.

Designed to simplify your workflow

To simplify your life even more, we’ve made the Apogee UV sensor turnkey with the ZL6 data logger and ZENTRA Cloud. Just plug the sensor into the logger and you’re up and running—no programming required. Bluetooth makes it easy to check the settings ensuring everything is just right. ZENTRA Cloud lets you see and share near-real time data with everyone on the project, from wherever you are, using any internet-connected device. No more trying to chase down the person who downloaded the data on an unknown hard drive.

More coverage for less

Backed by an industry-leading four year warranty and METER’s powerful ZENTRA system, Apogee’s ultraviolet sensor provides an easy, trustworthy, cost effective measurement of UV-A radiation, so you can get way more coverage—with way less hassle.

METER is trusted by

University of Idaho
Brigham Young University
Temple University
Campbell Scientific

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Calibration uncertainty ± 10%
Measurement range 0 to 100 W m-2
Measurement repeatability Less than 0.5%
Long-term drift Less than 2% per year
Non-linearity Less than 1%
Response time 0.6 s, time for detector signal to reach 95 % following a step change; fastest data transmission rate for SDI-12 circuitry is 1 s
Field of view 180°
Spectral range 300 to 400 nm (wavelengths where response is greater than 10 % of maximum; see spectral response below)
Directional (cosine) response ± 2 % at 45°, ± 5 % at 75°
Temperature response Less than 0.1% per C
Operating environment -30 to 85 C; 0 to 100 % relative humidity
Dimension 30.5 mm diameter, 37 mm height
Mass (5 m of cable) 140 g
Cable M8 connector (IP68 rating) to interface to sensor housing; 5 m of four conductor, shielded, twisted-pair wire with a TPR jacket; ZL6 stereo plug termination

Prop 65 warning

Data logger compatibility (not exclusive) METER EM60 series, ZL6 series, ZSC, ProCheck

A photo of the SU-221 Ultraviolet (UV) Sensor

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