Laurel Electronics LTS6 - Manual - Manual (Page 3)

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3. INTRODUCTION, RS232 OR RS485 SERIAL INPUT TRANSMITTER
The LTS6 serial input to analog output transmitter (or serial-to-analog converter) accepts RS232
or RS485 serial data using the Modbus or Custom ASCII protocol, and converts it to an isolated,
scalable 4-20 mA, 0-20 mA or 0-10V analog output. The unit fits on a 35 mm DIN rail and is only
22.5 mm (0.89") thick. It is normally powered by AC (85-264 Vac), but can optionally be powered
by low voltage AC or DC. All electrical connections are via detachable screw-clamp plugs. A
separate manual covers the LTSE6 serial input to analog output transmitter, which accepts
Ethernet data and converts to an isolated, scalable 4-20 mA, 0-20 mA or 0-10V analog output.
The current or voltage transmitter output is jumper selectable and is transformer isolated to avoid
ground loops. Either output provides 16-bit resolution of the output span and is ultra-linear to
within one bit. The output is scaled to the serial input in software. Output accuracy is ±0.02% of
span.
Dual solid state relays rated 120 mA at 140 Vac or 180 Vdc are standard. The relays can respond
to the transmitted serial values or to transmitted control characters, which override the internal
setpoints. The relays can also be controlled independently of the serial input by applying signals to
control inputs 1 and 2.
Isolation to 250V rms is provided for power, the serial data input, analog output, and relay
outputs. Isolation adds safety and avoids possible ground loops.
Default serial settings are for RS232 and full-duplex RS485. Half-duplex RS485 can be selected
via jumpers or external wiring.
Transmitter setup is via the unit’s serial port using an external PC and Instrument Setup software.
This software can be downloaded from our website at no charge. The required 3-wire transmitter-
to-PC interface RS232 cable is easy to build and is also available for purchase.
4. RECEIVING & UNPACKING YOUR TRANSMITTER
Your transmitter was carefully tested and inspected prior to shipment. Should the transmitter be
damaged in shipment, notify the freight carrier immediately. In the event the transmitter is not
configured as ordered or is inoperable, return it to the place of purchase for repair or replacement.
Please include a detailed description of the problem.