Four channel IP thermometer with PoE using external digital temperature probes



  • Web based monitor with up to four senors
  • email alerts when any sensor parameters go outside the designated range
  • PoE (Power Over Ethernet). No need for a power supply if you have POE Switch
  • Temperature and Temperature + Humidity senors
  • Temperature range can be up to -50 to 125°C depending on sensor used
  • Traceable calibration certificate included

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Parts Images Specifications Downloads

The P8641 is an IP based temperature monitor that can monitor up to 3 external probes connected to it. We have a variety of sensors with different cable lengths in the Sensors and Accessories section.

Measured values can be logged and downloaded from the unit, and alarms created if the mesurements go outside user set limits.

The P8641 is intended to be powered from a PoE enabled hub or switch, which removes the requirement of powering the P8641 locally. However, the P8641 can be powered from an optional 5V supply if required. In order to monitor temperature with this unit it is necessary to purchase temperature probes to connect to the P8641. There are a number of different probes available with different cables lengths and properties for different applications. All are waterproof.

A scalable product that may be used as a stand alone temperature monitor, or with up to 100 Comet units for a large multi-point/room solution which may be monitored using the optional monitoring software (order separately)



Setup and configuration of the P8641 is done using the TSensor program. This program allows the P8641 to be easily identified and configured once it is placed on the network. Download and usage instructions for TSensor can be found here.

Modes of Communication

Modbus TCP: Modbus TCP protocol enables to read measured values, set alarm limits, adjust the probe.
Telnet: Port 9999 enables the user to set alarm limits (lower, upper limits, hysteresis for temperature and time delay), e-mail addresses, SNMP addresses, probe description, refresh of www pages (10s to 65535s), set storing interval to history (10s to 65535s), enable each communication channel. Capacity of the history memory is 600 values. Password protection of this port is enabled. Automatic IP address assignment from DHCP server is also enabled.
Web pages: User selectable design of web pages enabling display of measurement history graphs. The user can design the look of web pages and temperature history.
SNMP: It is possible to read actual values and alarm limits. In case of alarm creation warning message (trap) is sent to addresses defined by the user (maximum three addresses).
SOAP: Online transmitter enables to send actual measured data in the format of SOAP message to selected web server in preset interval 10-65535 s.

Online transmitter enables to monitor measured values. In case of exceeding of adjusted limits warning message can be sent to specified addresses. There are the following options of alarm indication:

Alarm Indication Options

E-mail: In case of alarm creation warning e-mail message is sent to addresses defined by the user (maximum three addresses) or via e-mail to SMS message. Basic SMTP authentication is supported.
SNMP: In the case of exceeding of adjusted temperature limits, an alarm is activated and warning trap is sent to a user specified IP addresses (maximum 3 addresses).
Web pages: In the case of exceeding of adjusted temperature limits, an active alarm is displayed on web page.
syslog: Online thermometer enables to send text messages to selected syslog server after different events appear.

Synchronizing of time and measurement to web table. Measured values history is enabled by SNTP via Internet

Dimensions of the case (W x H x D): 88 x 74 x 39,5 mm

Power Supply - Please Note:This product does not include a power supply. If you require a power supply please order the power supply from the Sensors and Accessories Tab.

PoE requirnment:The PoE Injector/Switch needs to be IEEE.802.AF compatible.

How it works

This product needs to be connected to an Ethernet port in your building. Power the unit up, connect to an Ethernet port, make sure the sensor(s), if external, are connected and use our free software to locate the device on your web browser. The instruction set shows you how to do this.

Once located, you can use the web browser software to configure this unit with desired sensor values, name sensors and email address that needs to see the alarm.


For stock availability please call +44 1189 769 014 before placing an order Distributors




Downloads & Software

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