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BC Class C-R Low Energy FSR study materials
BC Class C-R Low Energy FSR study resources

BC Class C-R Low Energy FSR practice questions

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Question 1Codes, Standards, and Regulations

Under NFPA 58, what is the maximum water capacity of a single container used in a Class C cylinder exchange program?

  1. 420 pounds
  2. 239 pounds Correct answer.
  3. 1,000 pounds
  4. 108 pounds

Explanation

NFPA 58 limits cylinders used in cylinder exchange programs to a maximum water capacity of 239 pounds, which corresponds to roughly 100 pounds of LP-Gas. This threshold separates exchangeable consumer cylinders from larger containers requiring different handling rules.

Question 2Codes, Standards, and Regulations

Which document is the primary national standard governing the storage and handling of liquefied petroleum gas at consumer sites?

  1. NFPA 58 Correct answer.
  2. NFPA 30
  3. NFPA 70
  4. NFPA 54

Explanation

NFPA 58, the Liquefied Petroleum Gas Code, establishes requirements for storing, handling, and using LP-Gas, including container placement and safety distances. NFPA 54 addresses fuel gas piping inside buildings and NFPA 30 covers flammable liquids.

Question 3Codes, Standards, and Regulations

What does the designation FSR stand for in the context of LP-Gas personnel certification?

  1. Fuel Storage Regulator
  2. Fire Service Responder
  3. Field Safety Representative Correct answer.
  4. Facility Service Record

Explanation

FSR stands for Field Safety Representative, a person certified to perform specified regulated work such as installing and servicing LP-Gas systems. The role carries legal responsibilities defined by the authority having jurisdiction.

Question 4Codes, Standards, and Regulations

For a Class C-R low energy FSR scope, which type of work is typically authorized?

  1. Welding ASME pressure vessels
  2. Designing refinery process piping
  3. Low energy LP-Gas installations such as small cylinders and appliances Correct answer.
  4. Installing large bulk storage plants above 2,000 gallons

Explanation

The Class C-R low energy scope covers limited, low energy LP-Gas work such as connecting small cylinders to appliances and servicing low-demand systems. Bulk plant installation and pressure vessel fabrication fall outside this restricted certification.

Question 5Codes, Standards, and Regulations

Under NFPA 58, LP-Gas containers must be marked with which of the following?

  1. The installer's home address
  2. The container's water capacity and service pressure Correct answer.
  3. The delivery driver's license number
  4. The customer's account number

Explanation

NFPA 58 requires containers to be marked with key data including water capacity, service pressure, and manufacturer information so inspectors and users can verify ratings. Personal or account data is not a required container marking.

Question 6Codes, Standards, and Regulations

Which agency typically issues and enforces the FSR certificate in a Canadian province?

  1. The provincial safety authority such as Technical Safety BC Correct answer.
  2. The gas appliance manufacturer
  3. The insurance underwriter
  4. The local fire department

Explanation

Provincial safety authorities such as Technical Safety BC administer FSR certification and enforce the associated regulations. Fire departments and manufacturers may have related roles but do not issue the certificate.

Question 7Codes, Standards, and Regulations

What is the purpose of a pressure relief valve on an LP-Gas container?

  1. To measure the amount of gas remaining
  2. To filter impurities from the gas
  3. To prevent overpressure by discharging gas when internal pressure exceeds the set point Correct answer.
  4. To increase container pressure for better flow

Explanation

A pressure relief valve protects the container from overpressure by releasing gas when internal pressure reaches the valve's set point. This prevents rupture during fire exposure or abnormal heating.

Question 8Codes, Standards, and Regulations

Which of the following is a required qualification to hold an FSR certificate?

  1. Completion of approved training and examination Correct answer.
  2. Membership in a trade union
  3. A commercial driver's license
  4. Ownership of an LP-Gas business

Explanation

FSR certification requires completion of approved training and passing the applicable examination, demonstrating competence in the regulated work. Business ownership, union membership, and driving credentials are not certification prerequisites.

Question 9Codes, Standards, and Regulations

Under NFPA 58, what is the minimum separation required between an LP-Gas container and an ignition source such as a burner?

  1. Exactly 1 foot in all cases
  2. A distance specified by the standard based on container size Correct answer.
  3. Exactly 10 feet in all cases
  4. No separation is required

Explanation

NFPA 58 sets minimum separation distances that vary with container water capacity to reduce fire exposure risk. Fixed single distances do not apply across all container sizes.

Question 10Codes, Standards, and Regulations

A technician is connecting a 100-pound cylinder to a residential appliance. Which code primarily governs the appliance connection and venting?

  1. NFPA 13 only
  2. NFPA 58 and NFPA 54 together Correct answer.
  3. The local zoning bylaw only
  4. NFPA 70 only

Explanation

NFPA 58 governs the LP-Gas container and its installation, while NFPA 54 governs the gas piping and appliance connection downstream. Both standards apply together to a complete residential installation.

Question 11Codes, Standards, and Regulations

What must an FSR do before placing a new low energy LP-Gas installation into service?

  1. Obtain approval from the appliance manufacturer
  2. Notify the gas supplier only
  3. Perform required tests and provide documentation to the authority Correct answer.
  4. Wait 30 days for automatic approval

Explanation

The FSR must complete required pressure tests, verify compliance, and submit documentation to the safety authority before the installation is placed in service. Notification alone or waiting periods do not satisfy this obligation.

Question 12Codes, Standards, and Regulations

Under NFPA 58, cylinders stored indoors must meet which requirement?

  1. Storage is limited and connected cylinders must be minimized Correct answer.
  2. They must be stored horizontally
  3. They must be emptied completely before indoor storage
  4. They may be stored in any quantity if upright

Explanation

NFPA 58 limits indoor storage quantities and restricts connected cylinders to reduce fire hazard in occupied spaces. Horizontal storage and complete emptying are not the governing indoor storage rules.

Question 13Codes, Standards, and Regulations

Which factor most directly determines the required distance from an LP-Gas container to a property line?

  1. The age of the appliance
  2. The container's water capacity Correct answer.
  3. The owner's insurance policy
  4. The color of the container

Explanation

NFPA 58 separation distances from property lines scale with container water capacity because larger containers present greater potential hazard. Container color, appliance age, and insurance terms do not set code distances.

Question 14Codes, Standards, and Regulations

An FSR discovers a leaking relief valve on a small cylinder. What is the appropriate immediate action?

  1. Increase the regulator pressure to clear the leak
  2. Continue using the cylinder until empty
  3. Paint over the valve to seal the leak
  4. Remove the cylinder from service and follow emergency procedures Correct answer.

Explanation

A leaking relief valve indicates a safety defect, so the cylinder must be removed from service and handled per emergency procedures. Continuing use or attempting makeshift repairs risks uncontrolled gas release.

Question 15Codes, Standards, and Regulations

What record-keeping obligation typically accompanies FSR work on low energy installations?

  1. Filing records with the appliance manufacturer
  2. Retaining test and inspection records for the period required by the authority Correct answer.
  3. Recording only the customer's payment
  4. No records are required

Explanation

FSRs must retain test and inspection documentation for the retention period set by the safety authority so compliance can be verified later. Payment records and manufacturer filings do not fulfill this duty.

Question 16Codes, Standards, and Regulations

Under NFPA 58, what is required for electrical equipment installed in a classified LP-Gas area?

  1. Any household-grade equipment
  2. Equipment installed without regard to location
  3. Equipment with the lowest purchase price
  4. Equipment approved for the hazardous location class and division Correct answer.

Explanation

Electrical equipment in classified areas must be approved for the specific hazardous location classification to prevent ignition of flammable gas. Ordinary household equipment is not acceptable in these areas.

Question 17Codes, Standards, and Regulations

A customer wants to install a small LP-Gas appliance in a garage. Which consideration is most relevant under the codes?

  1. The homeowner's preferred schedule
  2. Ignition sources and ventilation in the space Correct answer.
  3. The garage's paint color
  4. The appliance brand's popularity

Explanation

Installing LP-Gas appliances in garages requires attention to ignition sources and ventilation because heavier-than-air gas can accumulate at low levels. Aesthetic or scheduling preferences do not affect code compliance.

Question 18Codes, Standards, and Regulations

Which statement best describes the relationship between an FSR certificate class and the work an individual may legally perform?

  1. The certificate only applies to residential work
  2. The certificate applies only to delivery driving
  3. Any certificate allows all LP-Gas work
  4. The certificate class defines the specific scope of authorized work Correct answer.

Explanation

Each FSR certificate class defines a specific scope of authorized work, and performing work outside that scope is non-compliant. A certificate is not a blanket authorization for all LP-Gas activities.

Question 19Codes, Standards, and Regulations

Under NFPA 58, cylinder exchange cabinets must be designed to meet which requirement?

  1. They must be fully sealed with no ventilation
  2. They must provide ventilation and protect cylinders from damage Correct answer.
  3. They must be made of wood
  4. They must be located indoors only

Explanation

Cylinder exchange cabinets must allow ventilation to prevent gas accumulation and protect cylinders from physical damage. Sealed, non-ventilated designs and indoor-only placement conflict with safety requirements.

Question 20Codes, Standards, and Regulations

An FSR is asked to sign off on an installation where the regulator vent is pointed upward and unprotected. What is the correct response?

  1. Approve it if the customer signs a waiver
  2. Require correction so the vent is oriented and protected per code Correct answer.
  3. Approve it because regulators are self-protecting
  4. Ignore the vent because it is a minor detail

Explanation

Regulator vents must be oriented and protected to prevent blockage by water, debris, or ice, which could cause overpressure. Sign-off should be withheld until the installation complies.

Question 21Codes, Standards, and Regulations

Which scenario would most likely exceed the scope of a Class C-R low energy FSR certificate?

  1. Replacing a hose on a 20-pound cylinder
  2. Inspecting an appliance connector for damage
  3. Connecting a patio heater to a small cylinder
  4. Installing a 1,000-gallon bulk storage tank at a commercial site Correct answer.

Explanation

Installing a 1,000-gallon bulk storage tank involves higher energy and larger volumes that exceed the low energy scope. Small cylinder connections and hose replacements fall within the restricted authorization.

Question 22Codes, Standards, and Regulations

A low energy installation shows evidence of gas odor near a buried line. Which action best reflects code-compliant practice?

  1. Cover the area with soil and continue
  2. Increase system pressure to push out debris
  3. Light a match to locate the leak
  4. Evacuate, eliminate ignition sources, and investigate per emergency procedures Correct answer.

Explanation

A suspected underground leak requires evacuation, elimination of ignition sources, and investigation following established emergency procedures. Covering the area or using open flame creates catastrophic risk.

Question 23Codes, Standards, and Regulations

Which combination correctly pairs an NFPA standard with its subject matter for LP-Gas work?

  1. NFPA 58 with LP-Gas storage and handling Correct answer.
  2. NFPA 13 with LP-Gas container placement
  3. NFPA 54 with electrical classification
  4. NFPA 70 with gas appliance venting

Explanation

NFPA 58 governs LP-Gas storage and handling, while NFPA 54 covers fuel gas piping and appliances and NFPA 70 covers electrical installations. Correctly pairing standards with their subjects is essential for compliance.

Question 24Codes, Standards, and Regulations

An FSR is evaluating whether a proposed installation requires notification to the authority before work begins. Which principle applies?

  1. Notification is required only after the work is complete
  2. Notification is never required for low energy work
  3. Notification is optional if the customer agrees
  4. Notification and permit requirements depend on the scope and jurisdiction rules Correct answer.

Explanation

Whether notification or a permit is required depends on the scope of work and the rules of the jurisdiction, so the FSR must verify local requirements before starting. Customer agreement cannot waive regulatory obligations.

Question 25Codes, Standards, and Regulations

Which item is most critical to verify when accepting a used LP-Gas cylinder for exchange?

  1. The cylinder's country of manufacture
  2. The customer's loyalty status
  3. The requalification date and valve condition Correct answer.
  4. The cylinder's paint finish

Explanation

Accepting a used cylinder requires verifying that it is within its requalification period and that the valve is in good condition, since these factors affect safe containment. Cosmetic and commercial details do not determine safety acceptance.

Question 26Codes, Standards, and Regulations

Which standard is the primary code governing the storage and handling of LP-Gas at a low energy installation?

  1. NFPA 25
  2. NFPA 54
  3. NFPA 58 Correct answer.
  4. NFPA 70

Explanation

NFPA 58, the Liquefied Petroleum Gas Code, sets the requirements for storing, handling, transporting, and using LP-Gas, so it is the core reference for low energy installations. The other standards address electrical systems, fuel gas piping in buildings, and water-based fire protection respectively.

Question 27Codes, Standards, and Regulations

Which body typically adopts the model LP-Gas codes and gives them legal force within a province or state?

  1. The appliance manufacturer
  2. The installing contractor
  3. The authority having jurisdiction Correct answer.
  4. The gas supplier's insurer

Explanation

Model codes such as NFPA 58 gain legal effect only when adopted by a jurisdiction, and the authority having jurisdiction enforces them. Manufacturers, insurers, and contractors may influence practice but cannot adopt or enforce regulations.

Question 28Codes, Standards, and Regulations

An FSR is planning a small LP-Gas installation and wants to confirm which edition of the referenced standard applies. What is the most reliable basis for that determination?

  1. The most recent edition published nationally Correct answer.
  2. The edition printed on the container nameplate
  3. The edition used when the appliance was built
  4. The edition cited in the locally adopted code

Explanation

The legally binding edition is the one adopted by the jurisdiction, which may lag or lead the newest published edition. Nameplates and appliance dates reflect manufacturing standards, not the code edition in force for the installation.

Question 29Codes, Standards, and Regulations

Under NFPA 58, which document is normally required to show that a new low energy LP-Gas installation was installed in accordance with the code before it is placed in service?

  1. A bill of lading from the supplier
  2. A material safety data sheet Correct answer.
  3. An equipment warranty certificate
  4. A completed installation and inspection record

Explanation

NFPA 58 expects installations to be verified against code requirements before being placed in service, and a completed installation and inspection record documents that verification. Shipping papers, warranties, and safety data sheets serve other purposes and do not demonstrate code compliance.

Question 30Codes, Standards, and Regulations

A small LP-Gas installation is proposed near a building opening, and the FSR must decide which code provision controls the required separation. Which approach best reflects how the codes are applied?

  1. Apply only the gas supplier's delivery guidelines
  2. Apply only the appliance manufacturer's recommendations
  3. Apply the most restrictive applicable requirement among the adopted codes Correct answer.
  4. Apply the least restrictive requirement to reduce installation cost

Explanation

Where more than one adopted code or standard sets a requirement for the same condition, the stricter provision governs so that safety is not reduced. Manufacturer instructions and supplier guidelines must still be followed, but they do not override adopted code minimums.

Question 31Low Energy FSR System Components and Materials

In a low-energy FSR system, which component is primarily responsible for detecting the presence of a person or object?

  1. The relay output module
  2. The power supply unit
  3. The analog-to-digital converter
  4. The sensor pad or mat Correct answer.

Explanation

The sensing pad or mat contains the resistive material whose resistance changes when pressure is applied, making it the primary detection element. Supporting electronics such as converters and relays only process or act on the signal the pad produces.

Question 32Low Energy FSR System Components and Materials

Which material property of the sensing foam or polymer is exploited by a low-energy FSR to register a footfall?

  1. Its change in thermal conductivity under compression
  2. Its change in magnetic permeability under compression
  3. Its change in electrical resistance under compression Correct answer.
  4. Its change in optical transparency under compression

Explanation

Force-sensing resistors rely on the piezoresistive effect, where compression brings conductive particles closer together and lowers resistance. The electronics measure this resistance change as a voltage signal. Optical, magnetic, and thermal effects are not the operating principle of a standard FSR mat.

Question 33Low Energy FSR System Components and Materials

What is the main reason low-energy FSR systems use a voltage divider with a fixed reference resistor?

  1. To filter out high-frequency radio interference
  2. To convert the sensor's changing resistance into a measurable voltage Correct answer.
  3. To amplify the sensor current to drive a relay directly
  4. To provide a stable clock for the microcontroller

Explanation

A voltage divider places the variable sensor resistance in series with a known resistor so the junction voltage reflects the sensor resistance. This voltage can then be sampled by an ADC. The divider does not amplify current, filter RF, or generate a clock.

Question 34Low Energy FSR System Components and Materials

Which type of battery is commonly chosen for a battery-powered, low-energy FSR mat because of its low self-discharge and stable voltage?

  1. Nickel-cadmium cell
  2. Lead-acid cell
  3. Lithium thionyl chloride cell Correct answer.
  4. Alkaline-manganese cell

Explanation

Lithium thionyl chloride cells offer very low self-discharge and a stable output, suiting long-deployment low-power sensing. Nickel-cadmium and lead-acid cells have higher self-discharge or are bulky. Alkaline cells are workable but lose charge faster and are less stable over temperature.

Question 35Low Energy FSR System Components and Materials

What role does the analog-to-digital converter play in a low-energy FSR system?

  1. It converts the analog sensor voltage into a digital value for processing Correct answer.
  2. It converts alternating current into direct current for the sensor
  3. It converts digital commands into physical pressure on the mat
  4. It converts the relay state into an audible alarm

Explanation

The ADC samples the analog voltage from the sensing divider and produces a numeric value the microcontroller can compare against thresholds. It does not generate pressure, rectify power, or sound alarms.

Question 36Low Energy FSR System Components and Materials

Which characteristic best distinguishes a 'low energy' FSR design from a continuously powered one?

  1. It sleeps between samples and wakes only to read the sensor Correct answer.
  2. It uses a higher excitation voltage to increase sensitivity
  3. It removes the ADC to save component cost
  4. It samples the sensor continuously at maximum rate

Explanation

Low-energy designs duty-cycle the electronics, keeping the controller asleep and waking periodically or on an interrupt to read the mat. Higher excitation or continuous sampling would increase consumption. Removing the ADC would prevent digital processing.

Question 37Low Energy FSR System Components and Materials

What is the function of the microcontroller in a low-energy FSR detection system?

  1. It physically deforms the sensing pad to test it
  2. It stores the mat's pressure in a hydraulic reservoir
  3. It reads the digitized sensor value and decides whether a person is present Correct answer.
  4. It supplies the mechanical force that triggers the sensor

Explanation

The microcontroller runs the detection logic, sampling the ADC output and applying thresholds or timing rules to decide presence. It does not create mechanical force or store pressure hydraulically.

Question 38Low Energy FSR System Components and Materials

Which wiring practice best preserves signal integrity in a low-energy FSR mat with long leads?

  1. Running the sensor leads parallel to mains wiring for shielding
  2. Twisting the sensor pair and keeping it away from power cables Correct answer.
  3. Using the thinnest possible conductors to reduce capacitance
  4. Connecting the sensor ground only at the far end of the run

Explanation

Twisted pairs and physical separation from power cables reduce induced noise and capacitive coupling on high-impedance sensor lines. Running alongside mains wiring increases interference, and thin conductors raise resistance.

Question 39Low Energy FSR System Components and Materials

A designer wants to reduce standby current in a battery-powered FSR mat that must still detect a footstep within 50 ms. Which approach is most appropriate?

  1. Replace the battery with a larger alkaline pack
  2. Increase the ADC sample rate to several kilohertz continuously
  3. Power the sensing divider from a linear regulator left always on
  4. Use an interrupt-capable comparator that wakes the controller on threshold crossing Correct answer.

Explanation

A comparator monitoring the divider can trigger a wake interrupt only when pressure crosses a threshold, keeping the controller asleep otherwise. Continuous high-rate sampling and an always-on regulator both raise standby current. A larger battery masks rather than reduces consumption.

Question 40Low Energy FSR System Components and Materials

An FSR mat reads a stable high resistance even when no one stands on it, and the reading barely changes under load. Which fault is most consistent with this symptom?

  1. An open circuit in the sensor lead or pad Correct answer.
  2. A reversed ADC reference voltage
  3. A short circuit across the sensor leads
  4. An oversized decoupling capacitor on the supply

Explanation

An open sensor path leaves the divider pinned near the high-resistance rail, and applied pressure cannot change a circuit that is already broken. A short would instead pin the reading low. Reference reversal or decoupling issues would not produce a load-insensitive high reading.

Question 41Low Energy FSR System Components and Materials

Why is a Schmitt trigger or hysteresis threshold often used when converting the FSR voltage into a presence decision?

  1. To convert resistance directly into a frequency
  2. To prevent chatter when the signal hovers near the threshold Correct answer.
  3. To shorten the battery life by increasing switching
  4. To increase the sensor's physical sensitivity to light loads

Explanation

Hysteresis sets separate turn-on and turn-off thresholds so small fluctuations near a single threshold do not cause rapid toggling. It does not change the sensor's physical sensitivity, deliberately shorten battery life, or perform resistance-to-frequency conversion.

Question 42Low Energy FSR System Components and Materials

A low-energy FSR mat must distinguish a standing person from a brief object drop. Which combination of features is most useful?

  1. Peak amplitude alone
  2. Peak amplitude together with the duration above threshold Correct answer.
  3. The battery voltage alone
  4. The ambient temperature alone

Explanation

A dropped object often produces a brief spike, while a person produces a sustained load; combining amplitude with time-above-threshold separates the two. Amplitude alone cannot tell a heavy brief impact from a lighter sustained presence, and battery voltage or temperature carry no occupancy information.

Question 43Low Energy FSR System Components and Materials

Which sensing material arrangement is most suitable for a large-area floor mat that must remain flexible and low cost?

  1. A rigid ceramic piezo disc bonded to a steel plate
  2. A conductive polymer foam sandwiched between conductive fabric electrodes Correct answer.
  3. A strain gauge glued to an aluminum beam
  4. A capacitive touch panel made of glass

Explanation

Conductive foam between fabric electrodes yields a flexible, inexpensive piezoresistive sandwich suited to large mats. Rigid ceramic, bonded metal beams, and glass panels are stiff, costly, or fragile for a walkable floor surface.

Question 44Low Energy FSR System Components and Materials

A designer measures 2.5 V at the divider midpoint with a 3.3 V supply and a 10 kΩ reference resistor. What sensor resistance is implied, assuming the sensor is the lower leg to ground?

  1. About 10 kΩ
  2. About 3.1 kΩ Correct answer.
  3. About 33 kΩ
  4. About 13.2 kΩ

Explanation

With the sensor as the lower leg, Vmid = Vsupply × Rsensor/(Rsensor + Rref). Solving 2.5 = 3.3 × R/(R + 10k) gives R ≈ 3.1 kΩ. The other values do not satisfy the divider equation for these conditions.

Question 45Low Energy FSR System Components and Materials

Why might a low-energy FSR system use a comparator instead of routing the analog signal into an ADC for continuous conversion?

  1. A comparator converts resistance into light
  2. A comparator draws less power while providing a simple threshold decision Correct answer.
  3. A comparator removes the need for a power source
  4. A comparator provides higher resolution than any ADC

Explanation

A comparator can make a binary threshold decision with very low quiescent current, avoiding the energy cost of continuous ADC conversions. It does not offer higher resolution than an ADC, eliminate power, or convert resistance to light.

Question 46Low Energy FSR System Components and Materials

What is the main trade-off when increasing the excitation voltage across an FSR sensing divider?

  1. Faster response versus loss of the ADC
  2. Improved linearity versus inability to detect weight
  3. Lower noise versus reduced sensor lifespan only
  4. Larger signal for easier measurement versus higher power and self-heating Correct answer.

Explanation

Higher excitation increases the voltage change per resistance change, improving measurement margin, but it also raises current draw and resistive self-heating. It does not eliminate the ADC or prevent weight detection.

Question 47Low Energy FSR System Components and Materials

A mat's detection thresholds drift between cold mornings and warm afternoons. Which design change best addresses this?

  1. Remove the reference resistor from the divider
  2. Increase the relay coil voltage
  3. Add temperature compensation or auto-calibration of the baseline Correct answer.
  4. Shorten the sampling window to a single reading per day

Explanation

Piezoresistive materials and electronics drift with temperature, so baseline tracking or temperature compensation keeps thresholds valid. Relay voltage, divider removal, or infrequent sampling do not correct thermal drift and may worsen reliability.

Question 48Low Energy FSR System Components and Materials

Which combination of components forms the minimal signal chain of a low-energy FSR presence detector?

  1. Sensing pad, divider, ADC or comparator, microcontroller Correct answer.
  2. Microphone, amplifier, speaker, battery
  3. Photodiode, transimpedance amplifier, laser, lens
  4. Sensing pad, motor driver, gearbox, encoder

Explanation

The pad converts pressure to resistance, the divider turns that into voltage, the ADC or comparator digitizes or thresholds it, and the microcontroller applies logic. Motor, audio, and optical chains do not match a resistive mat detector.

Question 49Low Energy FSR System Components and Materials

In a battery-powered FSR mat, why is a low-dropout regulator often preferred over a simple series resistor for supplying the sensing circuit?

  1. It eliminates the need for any decoupling capacitance
  2. It increases the battery's chemical capacity
  3. It converts the sensor resistance directly into a digital code
  4. It maintains a stable supply voltage as the battery discharges Correct answer.

Explanation

An LDO holds the output voltage steady even as the battery voltage falls, keeping divider readings consistent. It cannot increase chemical capacity, replace the ADC, or remove the need for decoupling.

Question 50Low Energy FSR System Components and Materials

A mat occasionally reports presence when a heavy object is placed on it but misses a light footstep. Which adjustment is most reasonable?

  1. Disconnect the reference resistor
  2. Raise the detection threshold further
  3. Lower the detection threshold while adding duration filtering Correct answer.
  4. Increase the relay coil current

Explanation

A light footstep produces a smaller signal, so lowering the threshold improves sensitivity, while duration filtering rejects brief heavy-object transients. Raising the threshold would worsen missed footsteps, and the other options do not affect sensitivity.