Low cost server environment monitor Hx531R
- temperature
- humidity
- power presence
- flood
- smoke
- air flow
- room entry
Server monitoring system is designed for 19-inch rack mounting, the height is one rack unit - 1U.
Rack-mount monitors are very convenient for cabinets.
The Hx531R monitor can be fitted into a rack "zero U" because of its thin design.
It can fit behind other equipment taking up space that is otherwise unusable.
Model H4531R is prepared for connection of external Pt1000 temperature probe and models H3531R, H7534R are equipped with 1 meter temperature + humidity probe.
Unit also contains three binary inputs for detection of two-state events - e.g. power presence, water, smoke, airflow, glass break detection, door contact.
Rack unit provides 5Vdc and 12dc power supply for external all sensors and detectors.
Large dual line LCD for simultaneous display of temperature, humidity is an advantage. Parameters are easy adjustable from transmitter keyboard or from the computer.
State-of-the-art capacitive polymer sensor ensures excellent calibration long term stability, inertia against water and condensation.
Environmental monitor is equipped with two relay outputs for alarm indication or control of external devices. Each relay can be assigned to any measured value.
Easy creation of online data acquisition system from several rack monitors by using new low cost database software Comet DBS Sensor Monitor - see also Accessories.

APPLICATIONS - online monitoring of temperature, humidity, power, flood, smoke, airflow, room entry at:
- server and computer rooms
- data centers
- rack monitoring
- industrial Ethernet
- building management and automation
- telecommunication devices
There are the following options of alarm indication:
ALARM INDICATION OPTIONS | |
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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 autentization is supported. |
SNMP: | In case of exceeding of adjusted temperature, humidity, pressure + computed value limits or binary input states alarm is activated and warning trap is sent to user specified IP addresses (maximum 3 addresses). |
WWW pages: | In case of exceeding of adjusted temperature, humidity, pressure + computed value limits or binary input states active alarm is displayed on www page. |
syslog: | Online transmitter enables to send text messages to selected syslog server after different events appear. E.g. after transmitter restart, alarm activation, communication error with SNTP, after firmware change, after alarm termination, after communication error with SOAP server. |
TECHNICAL PARAMETERS OF THE ONLINE SENSOR | |
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Maximum switching voltage, current, power of relay output: | 50V, 2A, 60VA |
Operating relative humidity range: | 0 to 100% |
Accuracy of relative humidity measurement: | ±2.5% relative humidity from 5 to 95% at 23°C |
Temperature measurement accuracy: | ±0.4°C |
Available temperature units: | degrees Celsius, Fahrenheit |
Accuracy and range of barometric pressure output: | ± 1.3hPa at 23°C range: 600 to 1100hPa |
Temperature operating range of case with electronics: | -30 to +80°C |
Temperature operating range of LCD display: | readable to operating temperature +70°C, it is recommended to switch OFF the LCD over +70°C |
Range of RH sensor temperature compensation: | -30 to +105°C |
Signal for binary inputs: |
from voltage-less contact, open collector or two-state voltage signal. Inputs are not galvanically isolated. |
Minimum pulse length at binary input: | 500 ms (shorter pulse may not be detected) |
Voltage at open contact: | 3.3 V |
Low voltage level: | 0 to +0.2 V |
High voltage level: | +3.0 to +30V |
Filtering ability of sensor cover: | 0.025mm - filter with stainless steel mesh |
Protection: | IP30 |
LAN connection: | RJ-45 connector |
Power: |
12 Vdc, maximum consumption 250mA. For power over Ethernet any PoE splitter is necessary e.g. DWL-P50 from D-Link company |
Power connector: | co-axial, diameter 5.5 x 2.1 mm |
Dimensions of the case: | 483 x 44 x 45 mm (W x H x D), one rack unit 1U |
Weight: | approximately 1100 g |
Warranty: | two years |
Model | Measured value | Maximum measuring ranges | Description |
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H4531R |
temperature+ 3 bin. inputs |
-200 to +600°C |
Temperature transducer for RTD Pt1000probes (not included). Accuracy of the input without probe +/-0,2°C |
H3531R |
temperature+ humidity+ 3 bin. inputs |
-30 to +105°C* including probe cable
relative humidity 0 to 100% |
Thermometer-hygrometer. Included T+RH probe with 1m cable. Cable lengths 2m or 4m available optionally. Humidity values available also as dew-point temperature, absolute humidity, specific humidity, mixing ratio, specific enthalpy. |
H7531R |
temperature+ humidity+ atmospheric pressure+ 3 bin. inputs |
-30 to +105°C* including probe cable
relative humidity 0 to 100% atmospheric pressure: 600 to 1100hPa accuracy: +/-1,3hPa at 23°C |
Thermometer-hygrometer-barometer. Included T+RH probe with 1m cable. Cable lengths 2m or 4m available optionally. Humidity values available also as dew-point temperature, absolute humidity, specific humidity, mixing ratio, specific enthalpy. Reading and pressure output in these units: hPa, kPa, mbar, mmHg, inHg, inH2O, PSI, oz/in^2. Barometer enables to measure sea level pressure by setting of correction to altitude above sea level. |
* Relative humidity at temperature over +85°C is limited in accordance with the graph. Near plastic case with electronics and probe cable maximum temperature is +80°C.

Figure: Working range of Ethernet sensor
Included accessory:
Traceable calibration certificate from the manufacturer, instruction manual.
Calibration certificate with declared metrological traceability of etalons is based on requirements of EN ISO/IEC 17025 standard.
Example of calibration certificate.
Set of four rack mounting screws is also included.
TSensor - freeware for online configuring of the transmitter is ready to download.
SensorReader - freeware for online logging values from one transmitter to a PC disk file is ready to download. Program enables to alarm acoustically the PC user if adjusted alarm limits are exceeded. Recorded values in CSV format are easy to process in e.g. Excel. Program can be started several times on a computer at the same time to monitor values from several transmitters.
For acquiring values from several transmitters, also third party software is possible to use. Tested functionality is with programs:
LabVIEW from National Instruments.
TIRS.NET - transmitters are also directly supported by program TIRS.NET from Coral s.r.o. company. Please download demo enabling full work with transmitters.
OPTIONAL ACCESSORY | ||
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DBS |
Database program DBS Sensor Monitor for online data acquisition and analysis from Comet sensors.
It contains all necessary components for monitoring of sensors, including one licence of DBV Database Viewer.
More information on online data acquisition. |
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SP008 | AC voltage presence sensor, connectable to binary Hx531 inputs. |
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LD12 |
Water leakage detector, two-state output, connectable to binary Hx531R inputs. With 3 meters cable. Powered from Hx531R 12Vdc output. |
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SD280 |
Optical smoke detector, relay output, connectable to binary Hx531 inputs, powered from Hx531R 12Vdc output. The SD280 detector combines an optical smoke sensor with a heat sensor. Both sensors have their outgoing signals processed digitally, resulting in higher false alarm immunity. |
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JS20 | P.I.R. motion detector is for interior protection. It detects object movement having a human body temperature. The JS-20 distinguishes itself with excellent RF immunity. The signal from the sensor is electronically analyzed. This ensures that the detector provides excellent sensitivity and false alarms are basically eliminated. The detection analysis rate can be adjusted to increase its immunity if the JS20 is installed in a problem location. It can be mounted on a flat wall or in a corner. Connectable to binary Hx531R inputs, powered from Hx531R 12Vdc output. |
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SA200A | Magnetic door contact, connectable to binary Hx531 inputs, without cable. |
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SA200A-2 SA200A-5 SA200A-10 SA200A-20 SA200A-30 |
Magnetic door contact, connectable to binary Hx531 inputs with cable lengths 2, 5, 10, 20, 30 meters. |
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MP047 |
Universal holder for probes for easy mounting to rack 19" (probes not included) |
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PP90 | right-angled stain-less steel flange for wall mounting. |
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SP006 | Tool for easy wire connection to terminals. |
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A1515 | ac/dc adapter 230V-50Hz/12Vdc. |
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DWLP50 |
DWL-P50 Power over Ethernet (PoE) adapter from company
D-Link.
The adapter is supposed to be connected to Ethernet switch supporting PoE. |
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accessory for calibration and adjustment of humidity by the user. |
Software and firmware for transmitters.
You can downlaod configuration programs and updated firmware from page Download - transmitters and transducers.
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