Pressure measurement — capabilities of strain-gauge transducers Strain gauge–based pressure transducers can be configured to measure which kinds of pressure references in industrial practice?

Introduction / Context:
Strain gauge pressure transducers convert diaphragm strain into an electrical signal using a Wheatstone bridge. By choosing the reference side and mechanical design, different pressure types can be measured.

Given Data / Assumptions:

• Transducers may use vented (gage), sealed (absolute), or dual-port (differential) references.
• Vacuum measurement is a subset of gage (pressures below ambient) when using a vented reference.

Concept / Approach:
Gauge sensors reference ambient (vented) and read positive or negative (vacuum) relative to atmosphere. Absolute sensors reference a sealed vacuum cavity. Differential sensors reference another process port. The same strain gauge principle supports all three by varying the reference configuration and diaphragm design.

Step-by-Step Solution:
Identify capabilities: strain-gauge bridges are versatile.Confirm that gage and vacuum are handled by vented designs; absolute by sealed vacuum; differential by two-port designs.Thus, options (a) and (b) are both true → choose “both (a) and (b)”.

Verification / Alternative check:
Manufacturers’ catalogs list gauge, absolute, and differential variants built on similar strain gauge platforms.

Why Other Options Are Wrong:

• Option (a) alone is incomplete; absolute/differential also possible.
• Option (b) alone is incomplete; gauge/vacuum also possible.
• Option (d) contradicts industrial reality.

Common Pitfalls:

• Assuming “vacuum” needs a special sensor; it is simply negative gauge pressure with a vented reference.

Final Answer:
both (a) and (b)