www.label.pl | LAB-EL Elektronika Laboratoryjna
Laboratory Electronics

CONCENTRATOR LB-731


  • functions: logger, interface of the LAB-EL meters
  • measurement: temperature, humidity, pressure
  • 16 channel temperature and humidity or pressure registry
  • signaling of exceeding the alarm levels
  • resistance to lacks in the power supply
  • cooperation with a PC computer
  • interfaces: RS-485, RS-232C, ethernet
Koncentrator LB-731

DESCRIPTION

Concentrator LB-731 is used for measurement result registry simultaneously from up to 16 measurement devices: hytherographs LB-710, LB-710D, LB-710L, LB-705, LB-725, thermometers LB-710T, LB-710DT, climate regulators LB-720, LB-720C or from other devices transmitting the measurement data using a digital current loop. In an optional version to a set number of inputs the pressure gauges can be attached LB-716P, LB-716D or barometers LB-716 or LB-750. The concentrator is also used for powering some of the sensors, those where the energy consumption does not exceed 15 mA (i.e. hytherograph LB-710, LB-710M, barometer LB-716). The concentrator also signals exceeding the threshold values of the attached devices measurement results.

Example solutions offered for big systems are discussed in detail in the measurement system description based on the concentrator LB-731.

The concentrator LB-731 is equipped with a built-in real time clock (RTC), which provides internal time base for the measurement intervals.

The concentrator is equipped with a memory of data collection of capacity sufficient enough for registry of 908 records from 16 sensors. Each record includes: date, time, humidity and temperature from all connected sensors. The type of data stored and the registry time interval (possible to be set in the scope between 1 ... 120 minutes) is programmed by a user. The following modes of registration are possible (one individual for each sensor): SMP - ( sample) sampling in set time registry intervals, RNG - ( range) registering scope of change: maximum and minimum measurement result in the period of registry interval and AVG - ( average) calculating average from all measurements during the time of registry interval and difference between maximum and minimum values.  

For each sensor input two individual alarm thresholds can be programmed by a user of temperature or humidity (top or bottom), of any values. Exceeding any thresholds of each sensor starts up an internal (in a concentrator) and an external (optional) alarm signal.

The memory of the registered data, all the settings and the concentrator's clock are internally battery powered and do not get canceled in case of lack in the energy supply. The period of time for powering the clock and the concentrator's memory is approximately 1 month (without the network supply).

Programming all of the mentioned above concentrator settings along with reading of the registered data can be performed by using a keyboard and a display built-in the concentrator or using a control interface RS232C from a supervision computer system. After attaching any PC computer with the interface RS232C it is possible to transfer data to a floppy disk and, process it and visualize the results according to the user's requirements. A PC program allowing on programming the settings is provided with the concentrator. The program allows on programming its settings and memory measurement readings (for the systems DOS and WINDOWS).  

The concentrator LB-731 is a base for the System of Parameter Production Monitoring (called later in the text SMPP) which supervises air temperature (and possibly humidity) in the monitored rooms and automatically notifies a user about any inconsistencies. It is done independently from the place where a user currently stays – through a SMS (to cellular phone) or thorough electronic mail. The system allows on storing information about status and measurements of sensors in the data base files for later reading and processing. The system can serve 16 concentrators and each can have 16 sensors type LB-710 connected to it (altogether it is possible to control simultaneously 256 places).        

TECHNICAL DATA 

MEMORY CAPACITY

908 entries (date, time, temperature, humidity) x 16 sensors.

REGISTRY INTERVAL

  • 1...120 minute
  • setting step - 1 minute.

CONTROL INTERFACE

  • transmission parameters: in accordance with RS232C, 9600 bps, 8 information bits, 1 stop bit.
  • TXD output - TXD line active stage - current 20 mA current, stand by stage - current 0 mA.
  • RXD output - RXD line active stage - current +2 mA, stand by stage - current less than 2mA.

SENSORS INTERFACE

Transmission parameters: in accordance with RS232C, 300 bps, 7 information bits, without evenness control,
1 stop bit. TXD output - TXD line active stage - current 25 mA, stand by stage - current up to 15 mA.

ALARM TRANSMITTER

Capacity 230V / 2A

OVERALL DIMENSIONS

(width x height x depth) 280 x 220 x 145 mm (casing made out of plastic).

POWER SUPPLY

  • 230V / 20VA / 50Hz
  • optionally 12V / 1A / DC

WORK TEMPERATURES

  • 0...+50 °C,
  • optionally -25...+50 °C
  • IP54 class.

SCOPE OF TEMPERATURES MEASURED 

  • measured temperatures: -99,9...+199,9 °C.
  • setting temperature alarm thresholds: -99...+149 °C.
  • setting humidity alarm thresholds: 1..99 %.
  • temperatures registry:
    • in a concentrator memory: -99,9...+102,3 °C,
    • in a PC computer program: -99,9...+199,9 °C.