Stevenson Screen Integration Station

Stevenson screenRadiation shield, ventilated

AC 220VTypical supply, wide-range optional

Dual uplinkGigabit Ethernet + RS485

IP67Outdoor enclosure

Product overview and engineering role

The SimtoLink Stevenson screen integration station is for meteorological IoT. Measurement and communications use a 24-bit Σ-Δ ADC, so long-term behavior stays predictable across wide temperature, wide supply, and electromagnetic interference. The screen gives natural ventilation and a radiation shield. Mounting height, orientation, and the surface under the screen have to follow WMO guidance, or the temperature and humidity series will carry a systematic bias. Terminals are pluggable, critical chips have a watchdog and redundant checks, and critical firmware is signed with rollback, which suits volume delivery and remote maintenance.

This model ships with Gigabit Ethernet and RS485 Modbus as a dual redundant pair, so it can sit in parallel on existing SCADA, a station archive, or an IoT platform. SimtoLink provides a southbound point-table template and a northbound MQTT/HTTP push example, which shortens joint commissioning. Volume projects can add the screen mount, cable glands, protocol mapping, and help with metrological traceability.

Reliability and site fit

On electrical safety and EMC, the station has passed the relevant CCC test items. Ports include surge and reverse-polarity protection. Reinforced grounding and a partitioned layout reduce ground loops and common-mode pickup. Outdoor or coastal sites can take a higher protection grade and an anti-corrosion coating.

Software can import parameters in a batch, apply threshold policies, and, where the model includes it, record events or waveforms. Configuration and firmware update over OTA. SimtoLink suggests three checks on site: power-on self-test, communications time sync, and a sample inspection. Metering or safety-related jobs can include help submitting the unit to a third-party metrology institute, plus type-test documents.

Key hardware parameters

The table is the typical build of this station, for selection and for tender clauses. A wider range, redundant power, or an intrinsically safe explosion-proof variant is quoted separately. Ask SimtoLink for the Hardware Specification and the Installation and Commissioning Guide. Order codes in the family can differ in detail. The nameplate and the documents shipped with the station prevail.

Parameter	Specification	Notes
Screen	Double-louver radiation shield with ventilation	Height, door facing, and surface under the screen per WMO or industry guidance
Temperature element	PT100 Class A	Traceable to IEC 60751
Air-temperature range	-40～60 ℃ (typical)	Wider range on order
Air-temperature accuracy	±0.15 ℃ (typical band)	Factory calibration certificate governs
Relative humidity	0～100 %RH	Non-condensing
Total radiation (optional)	Thermopile GHI, W/m²	Same family as the on-site pyranometer
Acquisition	24-bit Σ-Δ, channels sampled together	Timestamp and quality flag configurable
Supply	AC 220V (typical) / wide-range DC configurable	Outdoor lightning and surge protection by model
Communications	Gigabit Ethernet + RS485 Modbus RTU	Dual-channel redundant reporting
Ingress protection	IP67	Enclosure and gland options

Typical deployments

Three ways this station shows up in an IoT project, when you are laying out the scheme and the return:

National and regional station networks

As a backup for the primary station, or as an extra station that densifies the grid, minute air temperature, relative humidity, and radiation go into provincial quality control and assessment. Metadata records the probe tier and the comparison window.

PV plants and radiation reference fields

Temperature and humidity inside the screen are sampled with site global horizontal irradiance, for performance-ratio checks and module-temperature correction. Ethernet goes straight to the control room. RS485 keeps a local logger as backup.

Campuses and field trials

Modular terminals and an open register map make side-by-side comparisons repeatable in a paper. A quick-release build lowers the risk when students take the station apart. OTA and log export cover the audit at the end of a project.

Installation, grounding, and maintenance

Set screen height, door facing, and how open the plot is to WMO or industry practice, clear of shade and of heat from people or equipment. Fix the foundation, and leave a bonding point for lightning protection.
Before power-on, confirm AC or wide-range supply and the breaker rating. Keep a drain slope inside the outdoor terminal box, and torque the glands to the manual.
Put Ethernet on its own VLAN or a separate physical segment. Run RS485 as shielded twisted pair, grounded at one end, and do not parallel it with power cable for a long run.
For first go-live, finish time sync, register read and write, and quality-flag checks in the lab, then move the station to the plot.
In service, inspect louvers for dust, seals for aging, and probe shields every 6 months, and keep a comparison sample plus an archived log.

Ordering, documents, and support

SimtoLink can supply the hardware specification, dimension drawings, a wiring table, and a sample project for this station. Volume orders can include sample review and inspection at the factory. Warranty and calibration follow the contract and the papers packed with the unit.

Field patterns

A Stevenson screen station is the standard form of surface observation, built for long operational runs and for audited comparisons. The sites below differ in how representative the plot must be, and in the maintenance routine.

Backup for a national basic weather station

While the primary station is down for service, lightning recovery, or a failed sensor, this station takes over the minute upload. Metadata marks the instrument source and the comparison window. Two temperature and humidity probes have separate power and communications, so the service stays up and the assessment stays traceable.

Co-sited with a hydrological evaporation field

Set beside an E601 evaporation pan, a rain gauge, and a water-level observation, with the same ventilation, radiation shield, and surface under the instruments. Daily totals in hydrological-yearbook form go into the water-resources annual report, for drought monitoring and ecological-flow assessment.

Campus and public demonstration stations

Teaching, public open days, and research trials run on the same station. An open API feeds maker contests and digital-twin courses. Modular parts and quick-release terminals let students take it apart in a supervised lab.

Border posts and unattended grassland

A low-rate satellite link or a BeiDou short message fills the gaps. Solar tilt and shade are set for latitude and season. Rodent-resistant cable and a theft-resistant mount cut how often someone has to visit, and the site serves as ground truth for ecological remote sensing.