CST CST Data Communications & Indicator Systems 2

Question 1

What is RS-232 in the context of scale indicator communications?

Accepted Answer

An EIA serial communication standard for short-distance data transmission

Answer

RS-232 is an EIA serial communication standard commonly used to connect scale indicators to computers, printers, and data systems over short distances.

Question 2

What advantage does RS-485 have over RS-232 for multi-scale network installations?

Accepted Answer

Multi-drop capability supporting many devices on one cable with runs up to 1,200 meters

Answer

RS-485 supports multi-drop networks with multiple devices sharing one bus and cable runs up to 1,200 meters, making it far superior to RS-232 for scale networks.

Question 3

What is the purpose of a 'setpoint' output on a scale indicator?

Accepted Answer

To trigger a relay or digital signal output when the displayed weight reaches a programmed threshold

Answer

A setpoint output activates a relay or digital output signal when the displayed weight reaches a pre-programmed target weight, used to control filling, batching, or conveyor systems.

Question 4

In a Modbus RTU network, what role does a scale indicator typically play?

Accepted Answer

Slave device that responds to data requests from a PLC or computer master

Answer

In Modbus RTU networks, scale indicators typically act as slave devices, responding to read requests for weight data from a master PLC or supervisory computer.

Question 5

What does 'baud rate' determine in scale serial communications?

Accepted Answer

The speed of serial data transmission in bits per second

Answer

Baud rate defines the speed of serial data transmission in bits per second and must be set identically on both the scale indicator and the connected device for communication to work.

(CST) Certified Scale Technicians Practice Test

(CST) Certified Scale Technicians Practice Test

CST CST Data Communications & Indicator Systems 2