Model LT81VF4 includes:
Model LT81VF3 DIN rail transmitter by Laurel Electronics has Scaled rate, total, batch control, time based on rate, and custom curve linearization from factory-scaled analog signals., 4-20 mA or 0-10V analog output plus RS232 or RS485 I/O and dual relays. The model is configured for Extended main board and Low voltage power 10-48 Vdc or 12-30 Vac. It can track rate (such as gallons per minute or watts) or totalized rate (such as gallons or kilowatt hours) whether the transducer output is linear or requires square root extraction (differential pressure flow transducers).
Having an Extended Main Board, the transmitter can also perform custom curve linearization (provided by a curvilinear spline fit with up to 180 data points), display 1/ rate (such as the time it takes a conveyor to pass through an oven), and perform batch control for repetitive fill operations. Such applications typically make use of optional dual solid state relays, which are standard. External reset of totals is provided by a special connector.
The transmitter's signal conditioner board converts the full-scale 0-1 mA, 4-20 mA or 0-10 V analog signal to a frequency of 10 kHz to 110 kHz. This frequency is determined by measuring period over a selected gate time (from 10 ms to 200 s) and taking the inverse of period. At the lowest frequency of 10 kHz and the minimum gate time of 10 ms, the transmitter is capable of 25 updates per second. Scaling is done mathematically. Totals are stored in nonvolatile memory in case of power loss.
LTM Series serial output transmitters send data via an isolated serial port, which is user configurable for RS232 or RS485 and full or half duplex operation. 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 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 Datalogging Software.
Standard features of Laureate transmitters include:
For detailed transmitter information, specifications, dimensions and pricing, visit the following: