CONVERTER LB-470 (standard S300 for 2 outputs 4..20mA)


  • functions: standards' converter
  • digital input and output S300
  • 1 or 2 analogue outputs 4..20mA
  • additional calculating functions:
    • dew point temperature for the hytherographs
Konwerter LB-470

DESIGNED FOR

Converter LB-470 is used for changing the standard of a digital interface (so called S300), used in the meters of LAB-EL production, to a standard of the analogue signals 4..20mA, used often in the industrial automatic systems. The converter is produced in various versions, depending on a type of a LAB-EL meter with which it is supposed to cooperate. As an example, it can be: a hytherograph LB-710, an anemometer LB-476, a sun radiation meter LB-900 or other according to the orders.

It is possible to realize additional special functions through the converter LB-470 (i.e. calculating programmed for an individual order). As an example to a converter version cooperating with a hytherograph LB-710, it is possible to calculate in a converter a dew point temperature which result controls one of the converter’s outputs 4..20mA. 

The converters LB-470 can be connected in series where from one meter it is possible to receive any number of various (in a general case) the output signals 4..20mA. All of the outputs 4..20mA are isolated galvanically and work with an outside power supply (current sources).

CONSTRUCTION 

The converter LB-470 cooperates with a device equipped with an interface S300. The measurement data received by the converter are changed to a current interface in the scope 4..20mA with 16 bit resolution. A current value is proportional to currently received value sent from an attached measurement device. The converter stores in its non-volatile memory data concerning the scope of .. so called values fro which the output current gets a value 4 i 20 mA adequately. The scope of processing is programmed by the producer based on a specification of a person ordering a device. The scope of processing can be in the future changed  upon a user’s request. The converter is made in two versions with one or two transmitter channels 4..20mA.

The converter is equipped with an output in standard S300 used for retransmission of the received data. Because of such output the converter can be switched on in series in a system based on the interface S300. The converter is equipped with a lighting diode informing a user about a status in which the converter actually is. The converter is powered from a network 230V/50..60Hz.

The converter LB-470 is also a source of power supply for a cooperating with it device (a meter) with an interface S300. The current analogue converter outputs (4..20mA) as well as digital S300 are isolated galvanically between itself and the converter. The converter is locked in a casing adjusted for assembly on a bus rail TS35.

The producer in accordance with a specification of an ordering person stores to an internal non-volatile converter memory the values specifying the scope of such operation can be performed many times. For each analogue channel two values are introduced (MIN and MAX). If the actual value of a given value received by the interface S300 is smaller than the introduced MIN then the energy consumption forced in an analogue channel amounts to 4mA. For a value which exceeds MAX the current value is set for 20mA. If an input value stays between MIN and MAX then the current adopts a value: 4 + 16*(X-MIN)/(MAX-MIN) [mA] (where X it is a received number value from a meter).

In case of lack of reception of the input data (a device with an interface S300 is not attached) and in case of shortage in .. power supply a current of value 3,5 mA is forced, signaling incorrect system work.

TECHNICAL DATA

 INTERFACES
Input S300 Voltage
9...16V
Polarization random
Output S300 Accepted voltage 7...30V
Polarization random
Energy consumption (for 12V of output power supply) 1mA (stand by status), 25mA (active status)
Outputs 4..20mA Accepted voltage 7...30V DC
Polarization random
Energy consumption 3,5...20mA
Processing error (maximum) +/- 0,02 mA
RECOMMENDED CONSTANT WORK CONDITIONS *)
Scope of temperatures
0..50°C
Scope of humidity 20..80%
Level of environment corrosion aggressiveness accord. PN-71/H-04651 B
*) - Going beyond recommended constant work conditions (i.e. when installing the device in the open space) requires using additional protection means for the device's electronic part so that water out dropping does not start inside of the device (protecting the electronics with silicone or using additional external casing).
POWER SUPPLY
Scope of voltage 230V / 50Hz (possibility of ordering in a version with power supply voltage 12 V DC/AC)
Energy consumption 2 V

INTERFACE S300

Transmission parameters: in accordance with RS232C, 300 bods, 7 information bits, without evenness control,
1 stop bit working in a standard of a digital current loop.

FUNCTIONS INTERFACE OF THE S300

DEVICE CASING

Attention: The device should be installed inside an additional outside casing, i.e. wall switchgear. Climate category of additional outside casing has to be adjusted to conditions that control the installation place. The device is provided without cables (also without a power supply cable) as a component for installation only by an authorized person.

EXTENDED VERSIONS 

Upon a special request the following versions are available: