FNIRSI FNAC-28 Power Bank Output Testing Guide Malaysia

FNIRSI FNAC-28 Power Bank Output Testing Guide Malaysia

Introduction

Power banks are widely used in Malaysia for charging smartphones, tablets, wireless accessories and other portable electronic devices.

However, power bank performance can vary depending on battery condition, charging protocol compatibility, output voltage, connected load and internal power conversion efficiency.

A power bank advertised as 10,000mAh or 20,000mAh does not necessarily deliver the same numerical capacity at its USB output.

For electronics technicians, retailers and consumers, measuring USB output voltage, current and power provides useful information about actual power bank performance.

The FNIRSI FNAC-28 USB Tester is a compact instrument designed to monitor USB electrical parameters during compatible charging and discharging applications.

This guide explains how to use the FNIRSI FNAC-28 Power Bank Tester Malaysia for practical output testing, troubleshooting and understanding battery capacity measurements.

1. Why Test Power Bank Output?

A power bank contains rechargeable battery cells and electronic circuits that convert stored battery energy into regulated USB output power.

During operation, the power bank supplies electricity to a connected device.

Its actual performance depends on several factors:

Battery Cell Condition

USB Output Voltage

Charging Current Demand

Power Conversion Efficiency

USB Cable Resistance

Fast Charging Protocol Compatibility

Battery Temperature

Internal Protection Circuits

Testing these electrical parameters can help identify abnormal behaviour and compare different power banks under similar conditions.

For example, if a power bank repeatedly stops charging a connected device, technicians can investigate whether the output voltage or current changes before the interruption.

2. FNIRSI FNAC-28 Main Specifications

ParameterDescriptionModelFNIRSI FNAC-28Instrument CategoryUSB Digital TesterVoltage Measurement Range4V to 24VCurrent Measurement Range0A to 6.5AMaximum Rated Power156WUSB InterfacesUSB-A and USB Type-CMain MeasurementsVoltage, Current and PowerAdditional FunctionsCharging Monitoring and Cable Resistance TestingFast ChargingSelected Protocol Detection and TriggeringTypical ApplicationUSB Charger and Power Bank Testing

Important: The instrument's electrical ratings do not guarantee compatibility with every USB charging mode.

Users should verify the supported connections, operating limits and test procedures before testing a power bank.

3. How to Test Power Bank Output Voltage

Output voltage is one of the most important parameters when checking a power bank.

Many power banks provide a conventional USB output of approximately 5V.

Some models also support higher output voltages through compatible fast-charging protocols.

Step 1 - Prepare the Power Bank

Charge the power bank to an appropriate level before testing.

Inspect the housing, USB ports and cables for damage.

Do not test a power bank showing swelling, leakage, unusual heat or other signs of battery damage.

Step 2 - Connect the FNIRSI FNAC-28

Connect the tester to the compatible USB output of the power bank according to the manufacturer's instructions.

Step 3 - Connect a Suitable Load

Use a compatible smartphone, USB electronic load or another suitable device.

Some power banks require a minimum load to keep their output active.

Step 4 - Observe the Voltage

Read the output voltage displayed by the FNIRSI FNAC-28.

Step 5 - Monitor Voltage Stability

Observe whether the voltage remains reasonably stable while the connected load draws current.

Important: A voltage reading alone cannot determine the complete condition or remaining capacity of a power bank.

4. Understanding Power Bank Output Voltage

The following table shows examples of commonly encountered USB charging voltages.

Nominal Output VoltageTypical Application5VConventional USB Charging9VSelected Fast Charging Modes12VSelected Fast Charging Modes15VSelected USB PD Modes20VSelected Higher-Power USB PD Modes

These values are examples of USB charging systems, not a list of modes that the FNAC-28 can actively negotiate.

USB-C Power Delivery requires compatible communication between the source and connected equipment.

The FNIRSI FNAC-28 does not provide USB PD active triggering or PD packet capture.

For advanced USB PD testing, a dedicated USB PD analyser or suitable PD trigger equipment may be necessary.

5. How to Measure Power Bank Output Current

Output current indicates how much electrical current the connected device is drawing from the power bank.

The FNIRSI FNAC-28 measures current within its specified operating range.

For example, a smartphone may draw approximately 1A, 2A or another current depending on its charging conditions.

However, the power bank does not necessarily deliver its maximum rated current during every charging session.

The connected device and charging protocol influence actual current demand.

Example Measurements

VoltageCurrentCalculated Output Power5.0V0.5A2.5W5.0V1.0A5.0W5.0V2.0A10.0W9.0V2.0A18.0W12.0V1.5A18.0W

These are illustrative calculations, not actual FNIRSI test results.

For more consistent measurements, use a suitable controlled electronic load rather than relying only on a smartphone.

6. How to Calculate Power Bank Output Power

Electrical output power is calculated using:

Power (W) = Voltage (V) x Current (A)

For example:

Measured voltage: 5.1V

Measured current: 2.0A

Calculated output power:

5.1 x 2.0 = 10.2W

This indicates that approximately 10.2W is being delivered at the measurement point.

Another example:

Measured voltage: 9.0V

Measured current: 2.2A

Calculated output power:

9.0 x 2.2 = 19.8W

The measured power is approximately 19.8W.

Important: Output power and battery capacity are different measurements.

A power bank delivering 20W at one moment does not necessarily have greater energy capacity than a power bank delivering 10W.

7. Understanding Power Bank Capacity - mAh vs Wh

Power banks are commonly advertised using milliampere-hours, or mAh.

However, mAh alone does not fully describe stored electrical energy without knowing the corresponding voltage.

Electrical energy is more appropriately expressed in watt-hours (Wh).

The basic relationship is:

Energy (Wh) = Capacity (Ah) x Nominal Voltage (V)

For example, a power bank rated at 10,000mAh with a nominal battery voltage of 3.7V has a nominal stored energy of:

10Ah x 3.7V = 37Wh

A 20,000mAh power bank at the same nominal voltage has:

20Ah x 3.7V = 74Wh

These are theoretical nominal battery energy calculations.

The actual usable USB output energy is generally lower because of internal conversion losses and operating conditions.

Example Power Bank Capacity Table

Advertised CapacityAssumed Battery VoltageNominal Stored Energy5,000mAh3.7V18.5Wh10,000mAh3.7V37Wh20,000mAh3.7V74Wh30,000mAh3.7V111Wh

The calculations assume a nominal battery voltage of 3.7V. Actual product ratings may differ.

For meaningful comparisons, check the manufacturer's stated Wh rating and rated USB output capacity.

8. Why Does a 10,000mAh Power Bank Not Deliver 10,000mAh at 5V?

This is one of the most common questions about power bank capacity.

The advertised capacity is often based on the internal battery cells rather than the regulated USB output.

A power bank may use lithium battery cells with a nominal voltage around 3.7V.

Its electronic circuits then convert this battery voltage to a suitable USB output voltage.

Energy is lost during the conversion process.

Example Calculation

Assume:

Battery Capacity: 10,000mAh

Nominal Battery Voltage: 3.7V

Nominal Stored Energy: 37Wh

Assumed Conversion Efficiency: 85%

Estimated USB output energy:

37Wh x 0.85 = 31.45Wh

At a constant 5V output, the corresponding theoretical delivered charge is:

31.45Wh / 5V = 6.29Ah

Equivalent to approximately:

6,290mAh at 5V

This example demonstrates why a 10,000mAh battery rating should not be directly compared with USB output mAh.

The 85% efficiency is an illustrative assumption, not a guaranteed value for any particular power bank.

Actual results depend on the battery, electronics, temperature, output power and cutoff conditions.

9. Can FNIRSI FNAC-28 Measure Power Bank Capacity?

The FNIRSI FNAC-28 USB Tester provides USB charging monitoring functions.

Depending on its supported operating modes, accumulated charging measurements may help users observe electrical energy transfer over time.

However, users must distinguish between:

USB Output Charge: The total charge delivered through the USB output, normally expressed in mAh.

USB Output Energy: The electrical energy delivered through the USB output, expressed in Wh.

Internal Battery Capacity: The rated or measured capacity of the power bank's internal cells.

These are not interchangeable measurements.

A proper power bank capacity test requires a suitable load, a defined discharge procedure and accurate energy measurements over the complete test period.

The FNIRSI FNAC-28 should not be presented as a laboratory-grade battery capacity analyser.

10. How to Perform a Practical Power Bank Discharge Test

A controlled discharge test can provide more meaningful information than a single voltage reading.

Step 1 - Fully Charge the Power Bank

Charge the power bank according to its manufacturer's instructions.

Allow it to return to a suitable operating temperature before testing.

Step 2 - Connect a Compatible USB Tester

Connect the FNIRSI FNAC-28 using a supported connection arrangement.

Step 3 - Use a Suitable Electronic Load

Choose a load that is compatible with the power bank's output specifications.

Avoid exceeding the rated current of the power bank, cable, tester or load.

Step 4 - Record Output Measurements

Monitor voltage, current and power.

If supported by the instrument's measurement mode, record accumulated charge or energy.

Otherwise, use a suitable data-logging instrument for a complete discharge measurement.

Step 5 - Continue Until the Defined Test Endpoint

Observe the power bank until it reaches the appropriate discharge cutoff condition.

Do not bypass built-in battery protection.

Step 6 - Evaluate the Results

Compare the measured output energy with the manufacturer's rated USB output capacity, if available.

Important: A controlled discharge test should be conducted with suitable equipment and appropriate supervision.

11. Common Power Bank Problems and Troubleshooting

The FNIRSI FNAC-28 can help investigate several common power bank problems.

ProblemPossible CauseRecommended CheckPower Bank Not Charging DeviceOutput Disabled or Faulty ConnectionCheck Output Activation and CableLow Charging CurrentDevice Demand or Cable LimitationCompare with Known-Good EquipmentOutput Voltage DropsExcessive Load or Internal LimitationTest with Suitable Controlled LoadCharging Stops UnexpectedlyProtection Circuit or Low BatteryCheck Battery Level and LoadFast Charging Not WorkingProtocol IncompatibilityVerify Charger and Device StandardsOutput Power FluctuatesChanging Load or Thermal ControlMonitor Measurements Over Time

These observations provide troubleshooting clues but do not establish a definitive diagnosis.

12. Comparing Two Power Banks

Suppose a technician wants to compare two power banks under similar conditions.

The following values are hypothetical.

Test ParameterPower Bank APower Bank BAdvertised Capacity10,000mAh10,000mAhNominal Battery Energy37Wh37WhMeasured USB Output Energy30Wh32WhCalculated Energy Delivery Ratio81.1%86.5%

The energy delivery ratio is calculated as:

Measured USB Output Energy / Nominal Battery Energy x 100%

Under these test conditions, Power Bank B delivered more energy through its USB output.

However, this does not automatically establish the power bank's internal conversion efficiency because battery condition, usable cell energy and other losses may influence the result.

For a fair comparison, use the same discharge conditions and suitable measurement equipment.

13. Does Fast Charging Reduce Power Bank Capacity?

Fast charging can increase power transfer, but it may also increase electrical losses and heat depending on the power bank design.

A power bank operating at higher output power may deliver a different amount of usable energy compared with operation at a lower output power.

This can be influenced by:

Battery Internal Resistance

DC-DC Conversion Efficiency

Thermal Management

Output Voltage

Discharge Current

Battery Protection Settings

Therefore, capacity measurements performed at different output powers may not be directly comparable.

For reliable evaluation, use consistent test conditions.

14. Power Bank Testing Safety Precautions

Power banks contain rechargeable lithium batteries and should be handled carefully.

Before testing:

Inspect the Power Bank for Damage

Use Compatible USB Connections

Do Not Exceed Rated Current or Voltage

Avoid Short Circuits

Monitor for Unusual Heating

Use Suitable Electronic Loads

Do Not Bypass Battery Protection

Stop Testing if Swelling, Smoke or Abnormal Odour Occurs

Do not attempt to open or modify damaged lithium battery packs without appropriate professional procedures and equipment.

15. Who Should Use FNIRSI FNAC-28 for Power Bank Testing?

Mobile Phone Repair Shops

Technicians can investigate power bank charging problems and compare output behaviour.

Electronics Retailers

Retailers can demonstrate USB voltage, current and power measurements for compatible products.

Computer Service Centres

Service personnel can investigate portable charging accessories and USB power issues.

Electronics Training Centres

Students can learn about battery capacity, energy conversion and USB electrical measurements.

DIY Electronics Users

Hobbyists can monitor compatible USB power sources during low-voltage electronics projects.

16. Where to Buy FNIRSI FNAC-28 Power Bank Tester in Malaysia?

MTM Precision Sdn Bhd supplies electronic testing and measuring instruments for technical applications throughout Malaysia.

Customers looking for a FNIRSI FNAC-28 Power Bank Tester Malaysia can contact MTM Precision for product enquiries, pricing and stock availability.

Our team can also assist customers in selecting suitable USB testing equipment for charger, cable and power bank applications.

We serve customers in Kuala Lumpur, Selangor, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kedah, Kelantan, Terengganu, Perlis, Sabah and Sarawak.

Please contact us to confirm current stock and delivery arrangements.

Frequently Asked Questions

Q1. Can FNIRSI FNAC-28 test power bank output voltage?

Yes. It can measure compatible USB output voltage within its specified measurement range.

Q2. Can FNIRSI FNAC-28 measure power bank charging current?

Yes. It measures USB current flowing through a compatible test connection.

Q3. Can FNIRSI FNAC-28 measure power bank output power?

Yes. Output power can be determined from the measured voltage and current.

Q4. Can FNIRSI FNAC-28 measure actual power bank capacity?

It can assist with USB electrical monitoring. A complete capacity evaluation requires suitable discharge conditions and accumulated energy measurement.

Q5. Why does a 10,000mAh power bank deliver less than 10,000mAh at 5V?

The advertised capacity is often based on the internal battery voltage, while USB output operates at a different voltage. Conversion losses also reduce delivered energy.

Q6. Can FNIRSI FNAC-28 test fast-charging power banks?

It can perform compatible USB measurements and selected protocol tests, but it does not support USB PD active triggering or PD packet capture.

Q7. Is FNIRSI FNAC-28 suitable for electronics repair shops?

Yes. It is useful for preliminary USB power bank troubleshooting and output comparisons.

Q8. Where can I enquire about FNIRSI FNAC-28 in Malaysia?

Contact MTM Precision Sdn Bhd in Puchong, Selangor, for product pricing and availability.

Contact MTM Precision Sdn Bhd

For FNIRSI FNAC-28 USB Tester Malaysia, power bank testing instruments and electronics measurement equipment enquiries:

MTM Precision Sdn Bhd

Showroom & Service Centre

No. 29-1 & 29-2, Jalan Bandar 18,

Pusat Bandar Puchong,

47160 Puchong, Selangor, Malaysia.

Tel: 03-8080 7172

WhatsApp: +6016-660 7346

Email: mtmpre@yahoo.com

Website: www.mtmpre.com.my

Contact MTM Precision today for FNIRSI FNAC-28 pricing, availability and suitable USB power bank testing instrument recommendations in Malaysia.

Conclusion

Power bank testing involves more than checking whether a smartphone begins charging.

Understanding USB output voltage, current, power and electrical energy helps users evaluate charging behaviour and investigate common performance problems.

The FNIRSI FNAC-28 USB Tester provides useful measurement functions for compatible USB power bank applications.

By combining electrical measurements with suitable loading conditions, technicians can better understand power bank output behaviour and distinguish between charging power and stored battery capacity.

For customers searching for a Power Bank Tester Malaysia, USB Power Bank Output Tester Malaysia or FNIRSI FNAC-28 Malaysia, MTM Precision Sdn Bhd can assist with product enquiries and suitable testing equipment recommendations.