Laurel Electronics for Digital Panel Meters, Counters, Timers, Transmitters, Digital Displays

Digital Panel Meters - Counters - Timers
DIN Rail Transmitters - Large Digit Displays

    

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Load Cell & Microvolt Input
4-20 mA Current Transmitter
DIN Rail mounted, digitally programmable.
Exceptional accuracy at high update rates.

Features

  • Digital span adjust from 0 to ±99,999.
  • Digital zero adjust from -99,999 to +99,999.
  • 20, 50, 100, 250 & 500 mV full-scale ranges.
  • 4-20 mA or 0-10V isolated transmitter outputs, selectable.
  • Output resolution: 0.025% of span (12 bits).
  • Output accuracy: ±0.05% of span.
  • Update rate: to 60/sec.
  • Isolated 10V, 60 mA excitation supply to power up to two 350-ohm load cells in parallel.
  • 4- or 6-wire hookup to avoid supply and lead resistance effects.
  • DIN rail mount package only 22.5 mm thick.
  • Powered by AC or DC.
  • Detachable screw-clamp connectors.
  • Easy setup using PC-based Instrument Setup Software.
  • Optional dual solid state relays for alarm or control.
  • Optional custom curve linearization (Extended main board).

CE Mark       RoHS Mark

Description

Laureate 4-20 mA output, load cell or microvolt input transmitters are designed for use with load cells, strain gauges and microvolt input signals where exceptional sensitivity and stability are required. A most sensitive full-scale input range ±20 mV can be scaled internally to ±99,999 counts. The selected input range for the full 0-20 mA output span can be as wide as ±99,999 counts or as narrow as 150 counts, limited only by considerations of electrical noise and time constants of the programmable moving average digital filter.

Two output ranges are user selectable: 4-20 mA or 0-10V. Output isolation from signal and power grounds is provided by a separate on-board power supply, which can drive 20 mA into a 600 ohm load for 12V compliance. Output isolation eliminates problems caused by ground loops.

In most applications, output resolution and accuracy will be limited by the 12-bit digital to analog converter (DAC), which provides 4096 output levels, or steps equal to 0.025% of output span. These are 5 µV for 4-20 mA or 2.5 µV for 0-10V. Accuracy is ±0.05% of output span.

The transmitters are housed in a DIN rail case that is only 22.5 mm (0.89") thick. Signal connections are via detachable screw-clamp plugs.

Built-in Load Cell Excitation

A built-in, isolated, 10V, 60 mA excitation supply can power up to two 350-ohm load cells in parallel. Load cell connection can be via 4 or 6 wires. With 4-wire load connection, the transmitter operates in a ratiometric mode to eliminate errors due to supply variations. With 6-wire load connection, it also compensates for variation in resistance of the transducer leads, thereby allowing long cable runs.

Fast Read Rate

All Laureate analog input meters and transmitters use Concurrent Slope (Pat 5,262,780) analog-to-digital conversion, which allows up to 50 or 60 conversions per second, while integrating the signal over a full power line cycle. High read rate is ideal for peak capture and for real-time computer interface and control.

Selectable Signal Filtering

The internal digital readings and analog output can be separately selected to be either unfiltered or filtered.

  • An unfiltered selection updates after each conversion for fastest response, up to 60/sec, while integrating the input signal over a full power cycle. Fast read rate provides true peak readings and aids in control applications.

  • A batch average filter selection averages each 16 conversions for an update every 1/4 sec.

  • An adaptive moving average filter selection provides a choice of 8 time constants from 80 ms to 9.6 s. When a significant change in signal level occurs, the filter adapts by briefly switching to the shortest time to follow the change, then reverts back to its selected time constant. Another choice is Auto, which provides an automatic time constant selection based on the signal noise characteristics.

Easy Setup & Scaling

Transmitter programming is via a three-terminal RS-232 port using Laurel's PC-based Instrument Setup Software. This software can be downloaded from this website at no charge. The required transmitter-to-PC interface cable is available from Laurel (P/N CBL03). Scale and offset can be set by either of two methods:

  • With the coordinate reading method, the Laureate reads the high and low signal values, and the user enters the desired high an low reading values. The Laureate then calculates the span multiplier and offset. This method is ideal if an external calibration reference is available.
     

  • With the manual coordinate method, the user enters the high and low input values in Volts plus the desired high and low reading values. This method is suitable if no external calibration reference is available.

Specifications
 Laureate 4-20 mA Transmitters, Load Cell and Microvolt Input

Analog Input

 Range Resolution Input Ohms
Load Cell
 
 
 
  		     ±20.000 mV      
±50.0000 V
±100.00 V
±250.00 V
±500.00 V		 -99,999 to +99,999
zero adjust.
0 to ±99,999
span adjust.		 1 Gohm
Microvolt Meter
 
 
 
  		  ±20.000 mV 
±50.0000 V
 ±100.00 V
 ±250.00 V
 ±500.00 V		 1 µV
2.5 µV
5.0 µV
12.5 µV
25 µV		 1 Gohm
Input Resolution
Update Rate, Max
Max Applied Voltage		 16 bits (65,536 steps)
50/sec at 50 Hz, 60/sec at 60 Hz.
100 V
Analog Output
Output Levels
Compliance, 4-20 mA
Compliance, 0-10V
Output Resolution
Output Accuracy
Output Isolation		 0-20 mA and  0-10 Vdc (selectable)
10V ( 0-500 ohm load )
2 mA ( 5 kOhm load )
12 bits (4,096 steps)
±0.05% of output span
250V rms working, 2.3 kV rms per 1 minute test
Transducer Excitation Output (standard)
Jumper Selection 1
Jumper Selection 2
Jumper Selection 3		 10V @ 60 mA, isolated to 50V from signal ground
5V @ 50 mA, isolated to 50V from signal ground
15V @ 60 mA, non-isolated
Dual Relay Output (optional)
Relay Type
Load rating		 Two solid state relays, SPST, normally open, Form A
120 mA at 130 Vac or 170 Vdc, 28 ohms series resistance.
Power Input
Standard power
Low power option
Frequency
Power Isolation		 95-240V AC ±10% or 90-300V DC
12-30V AC or 10-48V DC
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test.
Mechanical
Case Dimensions
Case Mounting
Electrical Connections		 120 x 101 x 22.5 mm
35 mm rail per DIN EN 50022
Detachable screw terminal connectors
Environmental
Operating Temperature
Storage Temperature
Relative Humidity		 0°C to 70°C
-40°C to 85°C
95% at 40°C, non-condensing

Pinout
 Laureate 4-20 mA Transmitter, Load Cell and Microvolt Input

Pinout, 4-20 mA Current Transmitter, Loacd Cell & Microvolt Input

Shown with optional dual relay outputs. For 4-wire load cell
connection, jumper Pin 1 to Pin 2, and Pin 5 to Pin 6.

Load Cell Transmitter Connections
  

4-wire load cell bridge connection of load cell transmitter
In 4-wire connection, the excitation and sense lines are tied together. The transmitter can make ratiometric corrections for supply voltage variations, but does not compensate for variations in lead resistance. This connection is often used with short cable runs.

4-wire load cell bridge connection of load cell transmitter
In 6-wire connection, the sense lines are separate from the excitation lines, thereby eliminating effects due to variations in lead resistance. This allows long cable runs in outdoor environments with temperature extremes.

Up to six 350-ohm load cell bridges connected in parallel to a load cell transmitter
For large scales, up to four 350 ohm load cells in parallel can be powered by a single Laureate transmitter at 10V excitation. The excitation and sense points of the four bridges are connected in parallel through a summing box.

Ordering Guide
Laureate 4-20 mA Transmitter, Load Cell or Microvolt Input

Create a model number in this format: TA202WM. This is for a 4-20 mA output transmitter, standard main board, 95-240 Vac power, isolated dual solid state relays, and a load cell signal conditioner at the default setting 0-20 mV in = 4-20 mA out. Includes plug-in screw terminal connectors.
  
Transmitter
Type		 TA   Laureate 4-20 mA Transmitter. $235
Main Board 2  Standard Main Board.
4  Extended Main Board.
Note: Extended allows custom curve linearization and rate from successive readings.		 NC
$40
Power 0  Isolated 95-240 Vac & 90-300 Vdc
1  Isolated 12-30 Vac & 10-48 Vdc.		 NC
$30
Setpoint
Output		 0  None.
2  Isolated Dual Solid State Relays.		 NC
$30
Signal Input Load Cells (6-wire ratio)
WM    Default Scaling. 0-20 mV in = 4-20 mA out.
WM1  Custom Scaling.
In the write-in field of your invoice, specify min input, min reading; max input, max reading. Full-scale input is 20-500 mV. Includes isolated 10V dc excitation for up to four 350-ohm load cells in parallel.		  
$55
Accessories CBL03  RS-232 cable, TA to computer.
BL02  USB to RS-232 cable adapter.		 $19
$39
 
Laurel Electronics domestic orders Order from distributors for shipment to USA or Canada.
Laurel Electronics international orders Order online for international shipment.

 

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Laurel Electronics, Inc.
Industrial Instrumentation & Displays
3183-G Airway Avenue
Costa Mesa, CA 92626, USA
Phone: (714) 434-6131
Fax:     (714) 434-3766

  
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