4-20 mA Current Output Transmitter
for Duty Cycle Input
Transmits ON or OFF period in percent of total period.
DIN Rail mounted, digitally programmable.

Standard Features Isolated 4-20 mA or 0-10V transmitter outputs, selectable Transmits ON or OFF period as a percentage of total period Resolution of 1%, 0.1% or 0.01% Frequencies from 0.005 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 DIN rail mount package only 22.5 mm thick Plug-in screw-clamp connectors Easy setup with PC-based Instrument Setup Software 5V, 10V or 24V dc sensor excitation output, isolated Dual solid state relays for alarm or control, isolated RS232 or RS485 serial communications, isolated Universal AC power, 85-264 Vac Priced at only $275 (basic duty cycle transmitter) Options: Low voltage power, 10-48 Vdc or 12-32 Vac

Description
The Laureate 4-20 mA output 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 unit 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.
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 AC signals from 12 mV to 250 Vac. Jumper selections provide optimum operation for different sensor types and noise conditions.
Three analog transmitter settings are jumper selectable: 4-20 mA, 0-20 mA or 0-10V. The output tracks the reading from -999,999 to +999,999 counts that would be transmitted digitally. All selections provide 16-bit (0.0015%) resolution of output span and 0.02% output accuracy. Output isolation from signal and power grounds eliminates potential ground loop problems. The supply can drive 20 mA into a 500 ohm (or lower) load for 10V compliance, or 10V into a 5K ohm (or higher) load for 2 mA compliance. Standard features of Laureate transmitters include: Analog transmitter output, 16-bit, user scalable and isolated. User selectable 4-20 mA, 0-20 mA or 0-10V lsettings. Serial communications, isolated. User selectable RS232 or RS485, half or full duplex, Modbus or Laurel ASCII protocol. Dual solid state relays for control or alarm, isolated. Rated 120 mA at 130 Vac or 170 Vdc. Universal AC power supply for 85-264 Vac. Easy Transmitter programming is via Laurel's Instrument Setup Software, which runs on a PC under MS Windows. This software can be downloaded from this website at no charge. The required transmitter-to-PC interface cable is available from Laurel (P/N CBL04).

Specifications
Laureate 4-20 mA Transmitter for Duty Cycle Input

Duty Cycle Mode

Item Displayed
Display Units
Frequency Range
Input Accuracy

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

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

Pulse Input

Types

Grounding
Minimum Signal
Maximum Signal
Noise Filter
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).

Analog Output

Output Levels
Compliance, 4-20 mA
Compliance, 0-10V
Output Resolution
Output Accuracy
Output Update Rate
Output Isolation

4-20 mA and 0-10 Vdc (selectable)
10V ( 0-500 ohm load )
2 mA ( 5 kOhm load )
16 bits (65,536 steps)
0.02% of output span
25/sec max
250V rms working, 2.3 kV rms per 1 minute test

Sensor Excitation Output (standard)

Output Levels
Output Isolation

5V@100 mA, 10V@120 mA, 24V@50 mA (jumper selectable)
50V from signal ground

Dual Relay Output (standard)

Relay Type
Load Rating

Two solid state relays, SPST, normally open, Form A
130 mA at 140 Vac or 180 Vdc

Serial Communications (standard)

Signal Types
Data Rates
Output Isolation
Serial Protocols
Modbus Modes
Modbus Compliance
Digital Addressing

RS232 or RS485 (half or full duplex)
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
RTU or ASCII
Modbus over Serial Line Specification V1.0 (2002)
247 Modbus addresses.
Up to 32 devices on an RS485 line w/o a repeater.

Power Input

Standard Power
Low Power Option
Power Frequency
Power Isolation
Power Consumption

85-264 Vac or 90-300 Vdc (DC operation not UL approved)
10-48 Vdc or 12-32 Vac
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test
2W typical, 3W with max excitation output

Mechanical

Dimensions
Mounting
Electrical Connections

120 x 101 x 22.5 mm
35 mm rail per DIN EN 50022
Plug-in screw-clamp connectors

Environmental

Operating Temperature
Storage Temperature
Relative Humidity
Cooling Required

0°C to 55°C
-40°C to 85°C
95% at 40°C, non-condensing
Mount transmitters with ventilation holes at top and bottom.
Leave 6 mm (1/4") between transmitters, or force air with a fan.

Application Example of Duty Cycle Transmitter

Duty Cycle and Elapsed Time of a Laser
	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 4-20 mA Transmitter for Duty Cycle Input

Ordering Guide
Laureate 4-20 mA Transmitter for Duty Cycle Input
Click on the radio buttons to build a model number with pricing (shown below the Ordering Guide).

Quantity
Transmitter Type	LTA Laureate 4-20 mA Transmitter	$235
Main Board	8 Extended Main Board (required for duty cycle)	$40
Power	0 Isolated 85-264 Vac 1 Isolated 12-32 Vac or 10-48 Vdc	NC $30
Relay Output	0 None 2 Isolated Dual Solid State Relays	NC NC
Input Type	FR Dual-Channel Pulse Input	NC
Accessories	CBL04 RS-232 cable, LTA to computer or USB adapter CBL02 USB to RS-232 cable adapter	$19 $39