CST Electrical Systems & Mechanical Components 2

Question 1

What is the primary function of a shunt resistor in a weighing system's electrical circuit?

Accepted Answer

To provide a parallel current path for measurement

Answer

A shunt resistor provides a parallel current path that allows measurement of current without interrupting the main circuit.

Question 2

Which condition would cause a scale's analog-to-digital converter (ADC) to produce clipping errors?

Accepted Answer

Input signal exceeding the ADC's reference voltage

Answer

Clipping occurs when the input signal voltage exceeds the ADC's reference voltage, causing the converter to max out at its upper limit.

Question 3

A 4-wire load cell connection differs from a 6-wire connection in that it:

Accepted Answer

Lacks remote sense lines to correct for lead wire resistance drops

Answer

A 4-wire connection cannot compensate for voltage drops across lead wires, whereas a 6-wire connection uses remote sense lines to detect and correct this error.

Question 4

When testing insulation resistance on a scale's wiring harness, a reading below which value typically indicates a failure requiring repair?

Accepted Answer

1 MΩ

Answer

Insulation resistance below 1 MΩ indicates degraded insulation that can allow leakage currents to corrupt the measurement signal.

Question 5

What mechanical component absorbs shock loads and prevents overloading of the load cell in a platform scale?

Accepted Answer

Overload stop

Answer

Overload stops mechanically limit the deflection of the weighing platform, protecting the load cell from forces exceeding its rated capacity.

(CST) Certified Scale Technicians Practice Test

(CST) Certified Scale Technicians Practice Test

CST Electrical Systems & Mechanical Components 2