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Low-Cost Sensor for Up to Four Digital Probes, Ethernet Output and PoE

Low-Cost Sensor for Up to Four Digital Probes, Ethernet Output and PoE

The Web Sensor PA8641 is a universal Ethernet sensor designed to connect up to four digital temperature probes or combined temperature and humidity probes.

The device uses an independent bus for each channel, allowing a probe cable length of up to 40 m for each input separately. This allows individual probes to be placed more flexibly and at greater distances.

The device is suitable for monitoring multiple points in a single location, such as server rooms, technical rooms, or warehouses. Like other models, it offers a modern web interface, top-tier security including the option to upload custom certificates for HTTPS and TLS communication, and PoE support.

The device supports automatic detection and replacement of the same type of probes, simplifying maintenance and calibration.

Main Benefits:

  • Support for external digital temperature and humidity probes on a cable
  • Allows probe connection up to 30 meters in length
  • Power supply 5–24 V or PoE (IEEE 802.3af)
  • Integrated backup memory
  • Modern web interface, IPv4/IPv6 support, Modbus TCP, COMET Cloud, and fully encrypted communication (HTTPS, SNMPv3, TLS)
  • Integrated detachable bracket for easy installation

  • code
    PA8641
  • Warranty
    3 years
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Technical data

Measured value

Temperature
Relative humidity

TEMPERATURE SENSOR

Measuring range Depending on the connected DSxx probe
Accuracy Depending on the connected DSxx probe
Resolution 0.1 °C

HUMIDITY SENSOR

Measuring range Depending on the connected DSxx probe
Accuracy Depending on the connected DSxx probe
Resolution 0.1% RV

GENERAL TECHNICAL DATA

Operating temperature range -30 to +60 °C
Measurement channels 4× external temperature probe or 1× combined T+RH probe (cable-mounted), CINCH connector
Maximum probe cable length per channel 30 meters
Supported temperature units degrees Celsius (°C), degrees Fahrenheit (°F)
Power supply Power over Ethernet (IEEE 802.3af) or 5–24 V DC
Network interface Ethernet
IP support IPv4, IPv6
Communication protocols HTTP(s), Web server (WWW), HTTP GET (JSON, XML), Modbus TCP, SNMPv1, SNMPv2c, SNMPv3
Alarm protocols Email (SMTP), Syslog
Measurement interval 2 s
Ingress protection (IP rating) IP30
Dimensions 116 × 85 × 42 mm (without connected probe)
Weight 180 g
Warranty 3 roky

Cost-effective Ethernet Sensors without Display

The PAx6xx series is designed as a low-cost solution for applications where a local display or signaling is not required.

Ideal solution for:

  • server rooms
  • warehouses
  • IT racks
  • OEM projects
  • centrally managed systems

Why choose PAx6xx?

Cost-effective solution
Optimized for projects where the priority is:

  • reliability
  • network communication
  • remote monitoring
  • low acquisition costs

Full-featured network equipment
The same platform as TAx6xx means:

  • HTTPS
  • SNMP v1/v2c/v3
  • Modbus TCP
  • HTTP GET (JSON / XML)
  • HTTP POST (JSON)
  • SMTP (TLS)
  • IPv4 + IPv6
  • COMET Cloud
  • Syslog
  • Firmware update via web

✔ Modern security

  • Custom certificate upload
  • 4 user accounts
  • Encrypted communication
  • RTC with battery backup

✔ Flexible probe connection

  • Digital temperature probes (DST)
  • Digital T+RH probes (DSRH)
  • Independent bus for multi-input models
  • Up to 40 m cable length for each probe

Technical parameters (common)

  • Power supply 5–24 V (PA8652: 15–24 V)
  • PoE IEEE 802.3af
  • Backed-up memory
  • Modern compact design
  • Removable bracket
  • Operating range −30 to +60 °C

Typical applications

Server rooms

  • Discrete installation without a display.

Warehouses

  • Monitoring of multiple points using PA8641.

Technical rooms

  • Temperature + flooding + door status (PA8652).

Buildings with central monitoring

  • Integration into BMS via Modbus TCP or SNMP.

Optional accessories and download

Digital temperature probe for "p-line" WebSensor, CINCH connector, direct insertion

Digital temperature probe for "p-line" WebSensor, CINCH connector, direct insertion

code DST/C
Digital temperature probe DSTGL40/C, CINCH connector

Digital temperature probe DSTGL40/C, CINCH connector

Temperature range: -30 to 80°C
code SN189C
Digital temperature probe DSTGL40/C, CINCH connector, cable 2 meters

Digital temperature probe DSTGL40/C, CINCH connector, cable 2 meters

Temperature range: -30 to 80°C
code SN190C
Digital temperature probe DSTGL40/C, CINCH connector, cable 5 meters

Digital temperature probe DSTGL40/C, CINCH connector, cable 5 meters

Temperature range: -30 to 80°C
code SN191C
Digital temperature probe DSTGL40/C, CINCH connector, cable 10 meters

Digital temperature probe DSTGL40/C, CINCH connector, cable 10 meters

Temperature range: -30 to 80°C
code SN192C
Digital temperature probe DSTR162/C, CINCH connector

Digital temperature probe DSTR162/C, CINCH connector

Temperature range: -30 to 80°C
code SN215C
Digital temperature probe DSTR162/C, CINCH connector, cable 2 meters

Digital temperature probe DSTR162/C, CINCH connector, cable 2 meters

Temperature range: -30 to 80°C
code SN216C
Digital temperature probe DSTR162/C, CINCH connector, cable 5 meters

Digital temperature probe DSTR162/C, CINCH connector, cable 5 meters

Temperature range: -30 to 80°C
code SN217C
Digital temperature probe DSTR162/C, CINCH connector, cable 10 meters

Digital temperature probe DSTR162/C, CINCH connector, cable 10 meters

Temperature range: -30 to 80°C
code SN218C
Digital temperature probe DSTG8/C, CINCH connector

Digital temperature probe DSTG8/C, CINCH connector

Temperature range: -50 to 125°C
code SN228C
Digital temperature probe DSTG8/C, CINCH connector, cable 2 meters

Digital temperature probe DSTG8/C, CINCH connector, cable 2 meters

Temperature range: -50 to 125°C
code SN229C
Digital temperature probe DSTG8/C, CINCH connector, cable 5 meters

Digital temperature probe DSTG8/C, CINCH connector, cable 5 meters

Temperature range: -50 to 125°C
code SN230C
Digital temperature probe DSTG8/C, CINCH connector, cable 10 meters

Digital temperature probe DSTG8/C, CINCH connector, cable 10 meters

Temperature range: -50 to 125°C
code SN231C

Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, direct insertion

Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, direct insertion

Temperature range: 0 to 50°C
code DSRH/C
Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector

Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector

Temperature range: 0 to 50°C
code DSRH01+
Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, cable 2 meters

Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, cable 2 meters

Temperature range: 0 to 50°C
code DSRH02+
Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, cable 5 meters

Digital temperature/humidity probe for "p-line" WebSensor, CINCH connector, cable 5 meters

Temperature range: 0 to 50°C
code DSRH05+

AC/DC adapter 230Vac to 5Vdc/2.1 A, EU

AC/DC adapter 230Vac to 5Vdc/2.1 A, EU

code A1879eu
AC/DC adapter 230Vac to 5Vdc/2.1 A, UK

AC/DC adapter 230Vac to 5Vdc/2.1 A, UK

code A1879uk
AC/DC adapter 230Vac to 5Vdc/2.1 A, US

AC/DC adapter 230Vac to 5Vdc/2.1 A, US

code A1879us

Accredited temperature calibration

Accredited temperature calibration

code SLU001
Accredited temperature and relative humidity calibration

Accredited temperature and relative humidity calibration

code SLU003

KIT-GSM with modem

KIT-GSM with modem

code KIT-GSM-W
300Mbps Wireless N Nano Router

300Mbps Wireless N Nano Router

code TL-WIFI

Universal probe holder for easy mounting to rack 19"

Universal probe holder for easy mounting to rack 19"

code MP047
Wall holder for external probes DIGIL

Wall holder for external probes DIGIL

code SP009
Magnetic holder for Web Sensors PAxxxx and TAxxxx

Magnetic holder for Web Sensors PAxxxx and TAxxxx

code SP104

PTFE sensor protection, white

PTFE sensor protection, white

code F5300

COMET Database

COMET Database

code CDB
COMET Cloud

COMET Cloud

code cloud
COMET Cloud Lite for Android & iOS

COMET Cloud Lite for Android & iOS

code cloud_app
COMET VISION - Analytical Software for Dataloggers and Multiloggers

COMET VISION - Analytical Software for Dataloggers and Multiloggers

code CV
Database Viewer for Comet Database

Database Viewer for Comet Database

code DBV

COMET Magnetic Foldable Stand

COMET Magnetic Foldable Stand

code PPO001

Software

download-icon Comet Database One Click Installer (21.1-V)
487.31 MB
download-icon Database Viewer 3.20.0.0 dbapi 21.1
24.33 MB
download-icon Conversions - application for recalculation of values
694.50 KB
download-icon Virtual Channels Unlock for P8xxx
703.00 KB
download-icon COMET Cloud Lite - Android (Google Play)
download-icon COMET Cloud Lite - iOS (App Store)

Others

download-icon Terms and Conditions COMET System s.r.o.
133.12 KB

Manuals

download-icon Quick Start Manual
597.26 KB
download-icon Quick Start Manual
590.76 KB
download-icon Software development kit (SDK)
48.18 KB

Catalogs

download-icon CATALOG - WebSensor with Ethernet output
4.06 MB
download-icon Catalogue Sheets - COMET Premium WebSensors 2.0
107.88 KB

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We produce

Leading manufacturer of temperature, humidity, atmospheric pressure, carbon dioxide CO2 transmitters, data loggers, monitoring systems, data acquisiton systems, thermometers, hygrometers, barometers. Production includes data acquisition systems, humidity, temperature, CO2 transmitters and portable thermometers, hygrometers, barometers, CO2 meters. Instruments are designed for accurate measurement and for monitoring environmental conditions.

All instruments come with included traceable calibration certificate with declared metrological traceability of etalons based on requirements of EN ISO/IEC 17025 standard.

 

 

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