Stopwatch Input Modbus or Laurel ASCII Protocol Serial I/O Transmitter

(Resolution to 0.2 µs. Duration to 999,999 hrs. DIN Rail mounted, digitally programmable.)
Features Standard Main Board
  • Selectable Modbus or Laurel ASCII protocol.
  • Times single event time or accumulated time of all events.
  • 0.2, 2, 20, 200, 300V & 600V DC voltage ranges.
  • Timing duration to 999,999 hrs
  • Selectable HH.MM.SS clock format.
  • Triggers on positive or negative pulse edges.
  • DIN rail mount package only 22.5 mm thick.
  • Easy setup using Laurel's PC-based Instrument Setup Software.
  • Modbus RTU or ASCII modes, 2-wire connection, up to 247 digital addresses.
  • Timing resolution to 0.2 µs.
  • 2, 20, 200 mA and 5A DC current ranges.
  • Selectable H, M or S decimal format.
  • Inputs from NPN or PNP proximity switches, contact closures, digital logic, or magnetic pickups down to 12 mV.
  • Isolated 5V, 10V or 15V dc excitation output to power transducers
  • Detachable screw clamp plug connectors
  • Optional dual solid state relays for alarm or control.

timers3The Laureate TM Series serial output stopwatch transmitter performs all of the functions of the Laureate panel mount stopwatch, except for the display. The data retrieved via serial commands can be the time of individual events (Item #1) which produce start and stop pulses, or accumulated time of multiple events (Item #2). 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 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) can also be tracked.

freqbd2The 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 isolated 5V, 10V or 15V dc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.

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 Laurel 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.

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.

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- Laureate Serial I/O Transmitter, Stopwatch Input

Pulse Input
Types AC, pulses from NPN, PNP transistors, contact closures, magnetic pickups.
Ch A Frequency, Max 1 MHz.
Ch B Frequency, Max 250 kHz.
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 (typical)
Long-term Drift ±5 ppm/year
Stopwatch Operation
Timing Modes: + to + edge, or - to - edge.
With CH A only + to - edge, or - to + edge.
With CH A tied to CH B + edge of A to + edge of B, + edge of A to - edge of B,
With CH A and CH 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 Gate time + 30 ms
Gate Time Programmable from 10 ms to 199.99 s
Serial I/O
Signal levels RS485 (default) or RS232 (jumper selectable) 300, 600, 1200, 2400, 4800, 9600, 19200 baud
Data Rates 250V rms working, 2.3 kV rms per 1 min test.
Output Isolation Modbus RTU, Modbus ASCII, Laurel ASCII (selectable)
Serial Protocols 32 max without a repeater.
Devices on RS-485 Line 247 max
Modbus Addresses RTU or ASCII, 2-wire.
Modbus Modes Modbus over Serial Line Specification V1.0 (2002).10V @ 60 mA, isolated to 50V from signal ground
Modbus Compliance 5V @ 50 mA, isolated to 50V from signal ground 15V @ 60 mA, non-isolated
Transducer Excitation Output (standard)
Jumper Selection 1 10V @ 60 mA, isolated to 50V from signal ground
Jumper Selection 2 5V @ 50 mA, isolated to 50V from signal ground
Jumper Selection 3 15V @ 60 mA, non-isolated
Dual Relay Output(optional)
Relay Type Two solid state relays, SPST, normally open, Form A
Load rating 120 mA at 130 Vac or 170 Vdc, 28 ohms series resistance.
Analog Output (optional)
Output Levels 0-20 mA, 4-20 mA or  0-10 Vdc (selectable)
Compliance, 4-20 mA 10V ( 0-500 ohm load )
Compliance, 0-10V 2 mA ( 5 kOhm load )
Output Resolution 12 bits (4,096 steps)
Output Accuracy ±0.05% of output span
Output Isolation 250 V rms working, 2.3 kV rms per 1 minute test
Power Input
Standard power 95-240V AC ±10% or 90-300V DC
Low power option 12-30V AC or 10-48V DC
Frequency DC or 47-63 Hz
Power Isolation 250V rms working, 2.3 kV rms per 1 min test.
Case Dimensions 120 x 101 x 22.5 mm
Case Mounting 35 mm rail per DIN EN 50022
Electrical Connections Detachable screw clamp plug connectors
Operating Temperature 0°C to 70°C
Storage Temperature -40°C to 85°C
Relative Humidity 95% at 40°C, non-condensing

Application Example

Stopwatch Mode
timers3 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
timers6 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
timers5 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.
Pinout Laureate Serial Output Transmitter Stopwatch for Single Events or Accumulated Events
(shown with optional analog output and dual relay output)
Transmitter Powering a Single Sensor
tx-ta-dual2a tx-ta-dual3a
Transmitter Powering Two Sensors Transmitter with Active or Passive Sensors
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