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

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

    

Price List  |  Distributors  |  Search  |  Inquiry  |  Home

Duty Cycle Input
Modbus or Laurel ASCII Protocol Serial I/O Transmitter
 Transmits ON or OFF period in percent.
DIN Rail mounted, digitally programmable.

Features

  • Selectable Modbus or Laurel ASCII protocol.
  • Modbus RTU or ASCII modes, 2-wire connection, up to 247 digital addresses.
  • Transmits ON or OFF period as a percentage of total period.
  • Resolution of 1%, 0.1% or 0.01%.
  • Frequencies from .005 Hz to 10 kHz.
  • Inputs from NPN or PNP proximity switches, contact closures, digital logic, magnetic pickups down to 12 mV, or AC inputs up to 250 Vac.
  • Triggers on positive or negative pulse edges.
  • 5V, 10V or 15V dc excitation output to power sensors.
  • DIN rail mount package only 22.5 mm thick.
  • Detachable screw clamp plug connectors.
  • Easy setup using PC-based Instrument Setup Software.
  • Optional dual solid state relays for alarm or control.

Serial ASCII or Modbus Transmitter, Duty Cycle Input
CE Mark       RoHS Mark

Description
  

Duty Cycle Timing Diagram

The serial output of the Laureate duty cycle transmitter tracks ON or OFF period as a percentage from 0% to 100% of total period of repetitive pulse trains. In the illustration, duty cycle is 100 x t/P. The transmitter determines duty cycle by averaging an integral number of periods over a gate time, which is selectable from 10 ms to 199.99 s. The same signal is applied to Channels A and B. The meter divides the average pulse width by the period between pulses and expresses this ratio in percent. A resolution of 1%, 0.1% or 0.01% is selectable. By selecting leading or falling pulse edges, the ON or OFF duty cycle can be transmitted.

Duty cycle measurement is used to monitor modulated proportional control systems and pulse-modulated systems, such as radar, lasers or packet radio. For long periods, duty cycle can be measured by using the A and B channels of the Laureate dual-channel counter to totalize AC line cycles and having the counter display the ratio of the two totals scaled to percent.

Signal conditioner board used with Laureate Duty Cycle TransmitterUniversal Signal Conditioner

The dual-channel signal conditioner used for pulse detection accepts inputs from proximity switches with PNP or NPN output, TTL or CMOS logic, magnetic pickups, contact closures, and other signals from 12 mV to 250 Vac. Jumper selections provide optimum operation for different sensor types and noise conditions. A built-in 5V, 10V or 15V dc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.

Serial Data I/O & Programming

Laureate TM Series transmitters send data as a serial digital signal. RS485 or RS232 signal levels are jumper selectable and can each be associated with either the Modbus protocol or Laurel’s simpler Custom ASCII protocol.

  • Modbus protocol operation is fully compliant with the Modbus Over Serial Line Specification V1.0 (2002) for 2-wire, half-duplex connection. This includes RTU or ASCII modes, addressing of up to 32 devices per RS485 line without a repeater, and up to 247 digital addresses. Modbus operation allows devices by different manufacturers to be connected in parallel and be addressed using the same protocol.
     
  • Laurel’s Laurel ASCII protocol allows up to 31 Laureate devices to be addressed on the same RS485 data line. It is simpler than the Modbus protocol and is recommended when all devices are Laureates. It also allows use of Laurel’s datalogging software.

Transmitter programming is via the unit's three-terminal serial 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). Laurel's serial output transmitters and meters can also be part of PC-based data logging systems using Laurel's Datalogging Software, which operates under the Laurel ASCII Protocol. A single software command switches between the Modbus and Laurel ASCII Protocols.

Transmitter Options

Options include dual solid state relays for local alarm or control and an isolated 4-20 mA or 10V (selectable) analog output, effectively providing a linearized analog transmitter output that tracks the reading that would be transmitted digitally. The analog output provides 12-bit (4096 step) resolution of the output span and is ultra-linear to within one bit. Its accuracy is ±0.05% of span for all signal types, except for AC rms, where accuracy is ±0.1%. Output isolation from signal and power grounds is provided by a separate on-board power supply, which can drive 20 mA into a 500 ohm load for 10V compliance. Output isolation eliminates problems caused by ground loops.

DIN Rail Mounting 

Laureate transmitters are housed in a 35 mm DIN rail case that is only 22.5 mm (0.89") thick. Signal connections are via detachable screw clamp plug connectors.

Specifications
 Modbus or Laurel ASCII Protocol Serial I/O Transmitter,
Duty Cycle Input

Pulse Input
Types

Signal Ground
Minimum Signal
Maximum Signal
Maximum Frequency
Contact Debounce

AC, pulses from NPN, PNP transistors, contact closures, magnetic pickups.
Common ground for channels A & B.
Nine ranges from (-12 to +12 mV) to (+1.25 to +2.1V).
250 Vac
1 MHz, 30 kHz,  250 Hz (selectable).
0, 3, 50 ms (selectable).
Duty Cycle Mode
Item Displayed
Display Units
Frequency Range
Input Accuracy
Maximum Timing Interval

ON or OFF duty cycle of periodic pulse waveshape
1%, 0.1%, 0.01%
0.005 Hz to 50 kHz
0.01%, 0.005 Hz to 500 Hz, 0.1% at 5 kHz, 1% at 50 kHz
199.99 s
Update Rate
Conversion Interval
Gate Time
Time Before Zero Output

Gate time + 30 ms + 0-2 signal periods
Selectable 10 ms to 199.99 s
Selectable 10 ms to 199.99 s
Serial I/O (standard)
Signal levels
Data Rates
Output Isolation
Serial Protocols
Devices on RS-485 Line
Modbus Addresses
Modbus Modes
Modbus Compliance		 RS485 (default) or RS232 (jumper selectable)
300, 600, 1200, 2400, 4800, 9600, 19200 baud
250V rms working, 2.3 kV rms per 1 min test.
Modbus RTU, Modbus ASCII, Laurel ASCII (selectable)
32 max without a repeater.
247 max
RTU or ASCII, 2-wire.
Modbus over Serial Line Specification V1.0 (2002).
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.
Analog Output (optional)
Output Levels
Compliance, 4-20 mA
Compliance, 0-10V
Output Resolution
Output Accuracy
Output Isolation		 0-20 mA, 4-20 mA or  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
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 clamp plug connectors
Environmental
Operating Temperature
Storage Temperature
Relative Humidity		 0°C to 70°C
-40°C to 85°C
95% at 40°C, non-condensing

Application Example

Duty Cycle and Elapsed Time of a Laser
Measuring Duty Cycle and Elapsed Time of a Laser Using Laureate Meters or Transmitters Duty cycle can be used to indicate the ON time of a pulsed laser in relation to total time. Laureate counters and transmitters can also measure elapsed time, the number of pulses, average width in µs, the number of pulses, and total energy applied.

Pinout
 Laureate Serial Output Transmitter, Duty Cycle Input
(shown with optional analog output and dual relay output)

Pinout, Serial ASCII or Modbus Transmitter, Duty Cycle Input

                                   Transmitter Powering a Single Sensor
  

Pinout, Serial ASCII or Modbus Transmitter, Duty Cycle Input

 Pinout, Serial ASCII or Modbus Transmitter, Duty Cycle Input
Transmitter Powering Two Sensors Transmitter with Active or Passive Sensors

Ordering Guide
 Laureate Serial Output Transmitter, Duty Cycle Input

Create a model number in this format: TM8020FR. This example calls out a Modbus output transmitter, Extended main board, 95-240 Vac power, isolated dual solid state relays, no analog output, and a dual signal pulse input signal conditioner. Includes plug-in screw clamp connectors.
  
Transmitter
Type		 TM Laureate Transmitter, Modbus or Laurel ASCII Protocol. $210
Main Board 8  Extended Main Board (required or duty cycle) $40
  Note: Extended allows custom curve linearization and rate from successive readings. Not applicable to temperature.  
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
Analog Output 0  None.
1  4-20 mA or 0-10V analog output.		 NC
$25
Input Type FR  Dual-Channel Frequency.  NC
Accessories CBL03  RS-232 cable, TM to computer.
CBL02  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.

 

Price List  |  Distributors  |  Search  |  Inquiry  |  Privacy  |  Home

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

  
© 1996-2008 Laurel Electronics, Inc.