e of single events which produce start and stop pulses, or the accumulated time of multiple events. It can also time the width of a single pulse. The highest resolution is 0.2 µs, making the transmitter ideal for fast events. The longest timing interval is 999,999 hrs. For long events, the analog output is updated continuously during timing. There are two primary timing modes:
- A-A Stopwatch Mode. Time is measured between a start pulse and a stop pulse, both on Channel A, from either the positive or negative edges.
- A-B Stopwatch Mode. Time is measured between a start pulse on Channel A (positive or negative edge) and a stop pulse on Channel B (positive or negative edge). This mode allows inputs from different sources. In addition, the A and B inputs can be tied together to start the stopwatch with one polarity and stop it with the other polarity.
Event time (Item #1) is measured by counting 5.5 MHz clock pulses from a calibrated quartz crystal. The stopwatch output is updated during timing at a rate controlled by a gate time, up to 25/sec. Time is reset to zero when the next start pulse occurs. Accumulated time from multiple events up to 999,999 hours (Item #2) is also tracked.
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 24V dc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.
Standard features of Laureate LT transmitters include:
- 4-20 mA, 0-20 mA, 0-10V or -10V to +10V analog transmitter output, isolated, jumper-selectable and user scalable. All selections provide 16-bit (0.0015%) resolution of output span and 0.02% output accuracy of a reading from -99,999 to +99,999 counts that is also transmitted digitally. Output isolation from signal and power grounds eliminates potential ground loops.
- Serial communications output, RS232 or RS485 (half or full duplex), jumper selectable. Three protocols are user selectable: Modbus RTU, Modbus ASCII, or Laurel ASCII. Modbus operation is fully compliant with Modbus Over Serial Line Specification V1.0 (2002). The Laurel ASCII protocol is simpler than the Modbus protocol and is recommended when all devices are Laureates.
- Dual solid state relays, isolated, for alarm or control. Rated 120 mA at 140 Vac or 180 Vdc.
- Transducer excitation output, isolated. User selectable 5V@100 mA, 10V@120 mA or 24V@50 mA.
- Universal 85-264 Vac power. Low-voltage 10-48 Vdc or 12-32 Vac power is optional.
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).
- 4-20 mA, 0-20 mA, 0-10V or -10V to +10V transmitter output, 16 bits, isolated
- RS232 or RS485 serial data output, Modbus or Laurel ASCII protocol, isolated
- Dual 120 mA solid state relays for alarm or control, isolated
- Transmits single event time or accumulated time of all events
- Timing from 0.2 µs to 999,999 hrs
- Inputs from NPN or PNP proximity switches, contact closures, digital logic, or magnetic pickups down to 12 mV.
- 4-20 mA or 0-10V transmitter output, jumper selectable, isolated
- Analog output resolution 0.0015% of span (16 bits), accuracy ±0.02% of span
- 5V, 10V or 24V dc transducer excitation output, isolated
- Universal 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac power
|Types||AC, pulses from NPN, PNP transistors, contact closures, magnetic pickups.|
|Signal Ground||Common ground for channels A & B.|
|Minimum Signal||Nine ranges from (-12 to +12 mV) to (+1.25 to +2.1V).|
|Maximum Signal||250 Vac|
|Maximum Frequency||1 MHz, 30 kHz, 250 Hz (selectable).|
|Contact Debounce||0, 3, 50 ms (selectable).|
|Time Base Accuracy||Quartz crystal calibrated to ±2 ppm.|
|Span Tempco||±1 ppm/°C (typ)|
|Long-term Drift||±5 ppm/year|
|With CH A only||+ to + edge, or - to - edge.|
|With CH A tied to CH B||+ to - edge, or - to + edge.|
|With CH A and CH B||+ edge of A to + edge of B, + edge of A to - edge of B, - edge to A to - edge of B, - edge of A to - edge of B|
|Timing Interval||1 µs to 999,999 hrs|
|Timing Resolution||0.2 µs to 1 hr|
|Selectable Decimal Time||999999 H, M or S format with decimal point|
|Selectable Clock Time||HH.MM.SS format|
|Output Update Rate||Programmable gate time from 10 ms to 199.99 s + 30 ms|
|Analog Output (standard)|
|Output Levels||4-20 mA, 0-20 mA, 0-10 Vdc, -10 to +10Vdc (user selectable)|
|Compliance at 20 mA||10V (0-500Ω load)|
|Compliance at 10V||2 mA (5 kΩ or higher load)|
|Output Resolution||16 bits (65,536 steps)|
|Output Accuracy||±0.02% of output span|
|Output Update Rate||Programmed gate time + 30 ms + 0-2 signal periods|
|Output Isolation||250V rms working, 2.3 kV rms per 1 minute test|
|Serial Data Output (standard)|
|Signal Types||RS232 or RS485 (half or full duplex), jumper selectable|
|Data Rates||300, 600, 1200, 2400, 4800, 9600, 19200 baud|
|Output Isolation||250V rms working, 2.3 kV rms per 1 min test|
|Serial Protocols||Modbus RTU, Modbus ASCII, Laurel ASCII|
|Modbus Compliance||Modbus over Serial Line Specification V1.0 (2002)|
|Ethernet Connector||RJ45 jack for 10/100 Base-T Ethernet cable|
|RS232/485 Connector||Screw terminals for easy daisy chaining|
|Digital Addresses||247 for Modbus, 31 for Laurel ASCII|
|Dual Relay Output (standard)|
|Relay Type||Two solid state relays, SPST, normally open, Form A|
|Load Rating||120 mA at 140 Vac or 180 Vdc|
|Sensor Excitation Output (standard)|
|Output Levels||5V@100 mA, 10V@120 mA, 24V@50 mA (jumper selectable)|
|Output Isolation||50V from signal ground|
|Standard Power||85-264 Vac or 90-300 Vdc|
|Low Power Option||10-48 Vdc or 12-32 Vac|
|Power Frequency||DC or 47-63 Hz|
|Power Isolation||250V rms working, 2.3 kV rms per 1 min test|
|Power Consumption||2W typical, 3W with max excitation output|
|Dimensions||129 x 104 x 22.5 mm case|
|Mounting||35 mm rail per DIN EN 50022|
|Electrical Connections||Plug-in screw-clamp connectors|
|Operating Temperature||0°C to 55°C|
|Storage Temperature||-40°C to 85°C|
|Relative Humidity||95% at 40°C, non-condensing|
|Cooling Required||Mount transmitters with ventilation holes at top and bottom. Leave 6 mm (1/4") between transmitters, or force air with a fan.|
|The stopwatch mode is used to time single events between start and stop pulses on the same channel. Duration of a single wave shape can be measured by tying the A and B channels together.|
|Timing Process Dynamics|
|The start and stop pulses used for timing can be generated by the dual relays in a Laureate panel meter, counter, or transmitter. For instance, the start and stop pulse edges can be created as temperature passes two alarm setpoints, or as temperature cycles in a hysteresis control mode.|
|Replacing an Oscilloscope with a Laureate Meter or Transmitter|
|An oscilloscope is great for viewing and timing pulses in a lab. However, in fixed installations where digital timing accuracy and control outputs are required, a low-cost Laureate time interval meter or transmitter will be the instrument of choice. Resolution to 0.2 µs is feasible.|
|Instrumenting a Pulsed Laser System|
|Some of the many possibilities in instrumenting a pulsed laser system with Laureate dual-channel counters and transmitters: elapsed time, number of pulses, pulse width, pulse separation, duty cycle, and pulse rep rate.|
|Datasheet, Manual, Mechanical and Serial I/O info.|
4-20 mA Current & Serial Data Output Transmitter for Time of Single or Accumulated Events
- Brand: Laurel Electronics, Inc.
- Model: LT
- Availability: In Stock