TASI TA813B+ for Air Compressor Electrical Troubleshooting Malaysia
TASI TA813B+ for Air Compressor Electrical Troubleshooting Malaysia
Air compressors are critical equipment in many Malaysian factories, workshops and production facilities. When a compressor develops an electrical problem, technicians often need to determine whether the issue comes from the power supply, starter or VFD, motor, compressor load or control system.
The TASI TA813B+ True RMS Digital Clamp Meter provides functions including AC/DC current measurement, Inrush Current, True RMS, VFD voltage, frequency and AC/DC voltage measurement, making it useful for electrical troubleshooting of many compressor systems.
Why Check Compressor Starting Current?
An air compressor motor can draw a high current during startup.
The basic sequence is:
Compressor OFF → Motor Starts → Inrush Current → Motor Accelerates → Normal Running Current
If the compressor operates normally after startup but occasionally trips a breaker or protection device when switched on, measuring only normal running current may miss the important event.
The Inrush Current function on the TA813B+ allows technicians to investigate the startup condition.
Common Complaint: Compressor Trips During Startup
Suppose a factory reports:
“The compressor sometimes trips when starting, but after it starts everything seems normal.”
A systematic investigation may include:
Power Supply
↓
Protection Device
↓
Contactor / Starter / VFD
↓
Motor
↓
Compressor
Rather than immediately assuming the motor has failed, technicians can collect measurements from the electrical system and investigate the actual operating condition.
Measure Inrush and Running Current
Two useful readings are:
Starting Current
and
Running Current
These values answer different questions.
Inrush current shows what happens during startup.
Running current shows electrical behaviour after the compressor reaches normal operation.
Recording both gives technicians more information than relying on only one current measurement.
Compressor Running Current Is Higher Than Before
Another maintenance scenario is:
“The compressor still works, but its motor current has increased.”
This change deserves investigation, but it does not automatically prove an electrical failure.
Possible areas can include:
Compressor mechanical load
Motor condition
Supply voltage
Bearings
Cooling condition
Air-system pressure
VFD settings
Operating conditions
This is why trending is valuable.
Instead of asking only:
“Is 25A normal?”
the better question may be:
“This compressor normally operated at 20A under similar conditions. Why is it now drawing 25A?”
Historical data provides context.
VFD-Controlled Air Compressors
Many modern compressors use a Variable Frequency Drive to control motor speed according to compressed-air demand.
The system may look like:
Incoming Supply → VFD → Motor → Compressor
The TA813B+ includes a VFD voltage measurement function, making it relevant to technicians maintaining variable-speed compressor systems.
Troubleshooting may involve checking:
Incoming electrical supply
VFD fault code
Operating frequency
Motor current
Connections
Motor condition
Compressor load
Always use the compressor and VFD manufacturers' diagnostic information together with electrical measurements.
Compressor Does Not Reach Normal Speed
If the motor starts but does not reach the expected operating condition, technicians may investigate:
Supply → Drive / Starter → Motor → Compressor Load
For a VFD-driven compressor, frequency information can also help determine how the drive is commanding the motor.
The actual cause may be electrical, mechanical, control-related or process-related.
A clamp meter provides measurement data; it does not replace systematic diagnosis.
Check Current on the Correct Conductor
When using a clamp meter, technicians should clamp around the appropriate single current-carrying conductor.
Do not simply clamp around a complete multi-core cable containing conductors with opposing current directions.
For three-phase compressor motors, technicians may also need to compare current measurements between phases according to proper electrical procedures.
Large differences between comparable phase measurements may justify further investigation.
Three-Phase Current Comparison
For a three-phase compressor motor, a maintenance record might include:
MeasurementCurrentPhase L1RecordPhase L2RecordPhase L3Record
The objective is not simply to collect three numbers.
Technicians should consider:
Equipment operating condition
Motor specifications
Supply condition
Historical measurements
Manufacturer recommendations
An abnormal difference should trigger further investigation rather than an immediate conclusion about the cause.
Compressor Starts Too Frequently
Electrical measurement can also be useful when a compressor cycles more frequently than expected.
The technician may observe:
Start → Inrush → Run → Stop → Start Again
Frequent starting can place additional electrical and mechanical stress on equipment.
However, the root cause may not be the motor.
The compressed-air system, controls, pressure settings, leaks or operating demand may also require investigation.
Combine Clamp Meter and Temperature Measurement
Electrical problems can sometimes be accompanied by abnormal heating.
Depending on the application, maintenance teams may combine electrical measurements with temperature inspection.
For example:
Current Measurement
Temperature Check
A thermal camera can provide an even broader temperature pattern for components such as:
Electrical connections
Breakers
Contactors
Motor terminals
Distribution panels
Different instruments answer different maintenance questions.
Combine Electrical and Vibration Monitoring
Compressors and their motors are rotating machines.
This means electrical and vibration measurements can complement each other.
TA813B+
→ Current
→ Inrush
→ Voltage
→ Frequency
Vibration Meter
→ Mechanical vibration condition
For example:
Increasing Current + Increasing Vibration
may justify closer investigation of the complete motor-compressor system.
The measurements do not automatically identify the fault, but they provide useful evidence.
Preventive Maintenance for Air Compressors
Instead of waiting until the compressor stops, technicians can record baseline measurements while it is operating normally.
A simple record may include:
ItemBaselineCurrent InspectionInrush CurrentRecordRecordRunning CurrentRecordRecordSupply VoltageRecordRecordFrequencyRecordRecordVibrationRecordRecordTemperatureRecordRecord
When measurements change significantly under similar operating conditions, the maintenance team has a reason to investigate further.
TA813B+ for Compressor Control Circuits
Modern compressor systems may contain both AC power and DC control circuits.
For example:
AC Supply → Motor / VFD
and
AC Supply → DC Power Supply → Controller / Sensors / Relays
Because the TA813B+ supports AC and DC current measurement, it offers additional flexibility for technicians working across different sections of modern machinery.
Don't Replace the Compressor Based on One Reading
One of the biggest mistakes in troubleshooting is jumping directly from an abnormal measurement to a component replacement.
For example:
High Current ≠ Automatically Bad Motor
Possible causes may include:
Motor + Compressor Load + Supply + VFD + Mechanical Condition + Operating Pressure
Good troubleshooting uses measurements to narrow down the problem.
The goal is not merely to find an abnormal number.
The goal is to understand why the number changed.
TA813B+ in a Factory Maintenance Toolkit
For compressor maintenance, technicians may eventually use several instruments:
Clamp Meter
Electrical current and voltage
Vibration Meter
Mechanical condition
Thermal Camera
Temperature patterns
Tachometer
Rotational speed
Sound Level Meter
Noise monitoring where applicable
Insulation Tester
Motor insulation testing
The TA813B+ therefore fits as one part of a broader industrial maintenance toolkit.
Important Electrical Safety
Air compressor electrical systems can contain hazardous voltages and high currents.
Only appropriately trained personnel should perform measurements on energized equipment.
Always verify:
Measurement category
Voltage and current limits
Instrument condition
Test lead condition
Equipment configuration
PPE requirements
Site safety procedures
Follow the compressor, VFD and TASI operating instructions before performing measurements.
TASI TA813B+ for Air Compressor Maintenance Malaysia
Looking for the TASI TA813B+ True RMS Digital Clamp Meter for air compressor, motor, VFD or factory electrical maintenance?
Contact:
MTM Precision Sdn Bhd
Showroom & Service Centre
No 29-1 & 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
Supporting industrial customers throughout Selangor, Kuala Lumpur, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kelantan, Terengganu, Kedah, Perlis, Sabah and Sarawak.
26 Sep 2026
