A Capacitor Bank Factory Acceptance Test (FAT) Checklist verifies that a capacitor bank panel or system was manufactured, installed, connected and tested before shipment.
It verifies that
- Capacitor units,
- Reactors,
- Contactors,
- Fuses,
- Control circuits,
- Protective devices and
- Interlocks meet drawings, technical specifications and iec/ieee standards.
FAT makes the capacitor bank secure, dependable, and ready for power factor correction (or) harmonic filtering installation, commissioning & long term operation.
Purpose and Scope
This Factory Acceptance Test (FAT) Checklist is issued to verify that the Capacitor Bank assembly has been designed, manufactured and tested in strict accordance with the project specifications, applicable IEC standards and client requirements.
The FAT shall be conducted at the manufacturer’s works prior to dispatch & witnessed by the client’s representative (or) a third party inspection agency.
Scope
The scope of this checklist covers all LV & MV capacitor bank assemblies including fixed and automatic power factor correction (APFC) panels, detuned filter banks and harmonic filter systems.
All checks are to be performed, documented and signed off before the equipment is approved for shipment.
Applicable Standards
All tests and inspections shall be carried out in conformance with the following international standards and project-specific documents.
- IEC 60831-1/2
- IEC 60871-1
- IEC 61439-1/2
- IEC 60529
- IEC 60076-6
Documentation & Drawing Verification
Before any physical inspection (or) electrical testing commences all submitted design documents should be reviewed and confirmed as the latest approved revision.
The manufacturer shall present certified copies of all relevant drawings, data sheets & test certificates for scrutiny by the inspection team.
| Test Description | Observed | Status |
|---|---|---|
| General Arrangement (GA) drawing reviewed & matches nameplate | ☐ Pass ☐ Fail | |
| Single-line diagram (SLD) verified against approved project SLD | ☐ Pass ☐ Fail | |
| Schematic and wiring diagrams checked for correctness | ☐ Pass ☐ Fail | |
| Capacitor & reactor data sheets submitted and reviewed | ☐ Pass ☐ Fail | |
| Material certificates (capacitor, busbar, cable) available | ☐ Pass ☐ Fail | |
| Type test certificates available & within validity period | ☐ Pass ☐ Fail | |
| Bill of Materials (BOM) cross-checked with approved MDS | ☐ Pass ☐ Fail | |
| Quality Inspection Plan (QIP) reviewed & accepted | ☐ Pass ☐ Fail |
Visual and Mechanical Inspection
A comprehensive visual and mechanical inspection shall be carried out on the assembled capacitor bank panel.
The purpose is to verify the quality of workmanship, correct identification of components, proper cable routing and dressing and the structural integrity of the enclosure.
All observations shall be recorded.
| Test Description | Observed | Status |
|---|---|---|
| Enclosure dimensions and IP rating (IP31 min / IP54 outdoor) verified | ☐ Pass ☐ Fail | |
| Enclosure finish: paint shade, thickness, and adhesion tested | ☐ Pass ☐ Fail | |
| Nameplates and equipment labels legible and correctly positioned | ☐ Pass ☐ Fail | |
| Busbar sizing, material (Cu/Al), and colour coding per IEC 60446 | ☐ Pass ☐ Fail | |
| Busbar joints torqued to specified values with correct hardware | ☐ Pass ☐ Fail | |
| Capacitor units: correct KVAR, voltage, and quantity installed | ☐ Pass ☐ Fail | |
| Detuning reactors (p-factor 7% / 14%) installed and rated correctly | ☐ Pass ☐ Fail | |
| Cable routing: segregation of power and control cables maintained | ☐ Pass ☐ Fail | |
| Earth bar sizing and continuity throughout panel verified | ☐ Pass ☐ Fail | |
| MCBs, contactors, and fuses: correct ratings and manufacturer approved | ☐ Pass ☐ Fail | |
| PF controller (relay) installed with correct settings and wiring | ☐ Pass ☐ Fail | |
| Anti-condensation heater with thermostat installed (if specified) | ☐ Pass ☐ Fail | |
| Ventilation louvers with filters present and unobstructed | ☐ Pass ☐ Fail |
Electrical Tests
Insulation Resistance Test
Insulation resistance (IR) tests shall be conducted using a calibrated 1000 V DC Megger (for LV systems) (or) 2500 V DC (for MV systems) on all power circuit conductors, busbars, and capacitor bank terminals against earth.
Tests shall be performed with all capacitor units disconnected and contactors in open position. Minimum acceptable IR value is 100 MΩ at 1 kV for one minute duration.
| Test Description | Observed | Status |
|---|---|---|
| IR test – Phase R to Earth (MΩ) | ☐ Pass ☐ Fail | |
| IR test – Phase Y to Earth (MΩ) | ☐ Pass ☐ Fail | |
| IR test – Phase B to Earth (MΩ) | ☐ Pass ☐ Fail | |
| IR test – Phase-to-Phase: R-Y, Y-B, B-R (MΩ) | ☐ Pass ☐ Fail | |
| Control circuit IR test (500V DC) against earth (MΩ) | ☐ Pass ☐ Fail |
High Voltage (Dielectric) Test
A power frequency high voltage (HV) withstand test shall be applied to all main power circuits as per IEC 61439. Test voltage shall be applied for 60 seconds with no flashover, puncture, or disruptive discharge. All semiconductor devices and electronic components shall be disconnected prior to the test.
| Test Description | Observed | Status |
|---|---|---|
| HV test voltage applied (kV AC, 50 Hz, 60 sec) | ☐ Pass ☐ Fail | |
| Result – Phase R: no flashover / breakdown | ☐ Pass ☐ Fail | |
| Result – Phase Y: no flashover / breakdown | ☐ Pass ☐ Fail | |
| Result – Phase B: no flashover / breakdown | ☐ Pass ☐ Fail | |
| Control circuit withstand test (2 kV, 1 min) | ☐ Pass ☐ Fail |
Functional and Operational Tests
Functional testing verifies that the automatic power factor correction (APFC) relay, switching contactors, step control logic, and protection circuits operate correctly under simulated load conditions. Each capacitor step shall be switched in and out under control of the PF relay, and the correct sequential operation verified. Protection relay settings shall be verified against the approved setting schedule.
| Test Description | Observed | Status |
|---|---|---|
| APFC relay target PF setting verified (e.g., 0.95 lag) | ☐ Pass ☐ Fail | |
| Step-1 contactor: energise and de-energise operation confirmed | ☐ Pass ☐ Fail | |
| Step-2 contactor: energise and de-energise operation confirmed | ☐ Pass ☐ Fail | |
| Step-3 and subsequent steps: correct operation confirmed | ☐ Pass ☐ Fail | |
| Alarm output (over-voltage / over-temperature) functional test | ☐ Pass ☐ Fail | |
| Discharge resistor function: voltage discharged within 3 min (IEC 60831) | ☐ Pass ☐ Fail | |
| MCB trip and re-close tested on each capacitor feeder | ☐ Pass ☐ Fail | |
| Indication lamps and mimic display verified | ☐ Pass ☐ Fail | |
| Door interlocks and safety earthing mechanism functional test | ☐ Pass ☐ Fail | |
| Anti-condensation heater thermostat set-point and operation verified | ☐ Pass ☐ Fail |
Protection and Metering Verification
All protection relays, current transformers (CTs), and metering devices incorporated in the capacitor bank panel shall be individually verified for accuracy, polarity, and correct wiring. CT ratios, burden ratings, and class designations must match the approved data sheet. Metering accuracy shall be tested against a calibrated reference instrument. Protection relay settings shall be confirmed against the approved relay setting schedule and a secondary injection test report shall be provided.
| Test Description | Observed | Status |
|---|---|---|
| CT ratio and accuracy class verified (e.g., 100/5A, Cl. 1.0) | ☐ Pass ☐ Fail | |
| CT polarity and wiring verified (P1/S1 correct) | ☐ Pass ☐ Fail | |
| Ammeter accuracy verified against reference meter (%) | ☐ Pass ☐ Fail | |
| Voltmeter accuracy verified against reference meter (%) | ☐ Pass ☐ Fail | |
| kVAR meter / power factor meter calibration verified | ☐ Pass ☐ Fail | |
| Over-current relay (OCR) – secondary injection and pickup confirmed | ☐ Pass ☐ Fail | |
| Earth fault relay – secondary injection and pickup confirmed | ☐ Pass ☐ Fail | |
| Over-voltage / under-voltage protection relay verified | ☐ Pass ☐ Fail | |
| Temperature relay set-point verified and alarm tested | ☐ Pass ☐ Fail |
Safety and Earthing Checks
Earthing continuity is a critical safety requirement for all electrical equipment. The entire enclosure frame, busbar earth bar, component mounting plates, and external earth terminals must demonstrate low-resistance continuity to the main earth point. All the exposed conductive parts shall be bonded to earth in accordance with IEC 61439 requirements.
In addition
- Safety labels,
- Warning notices and
- Access restrictions
must be inspected as part of the safety verification.
| Test Description | Observed | Status |
|---|---|---|
| Earth continuity: enclosure frame to main earth terminal (< 0.1 Ω) | ☐ Pass ☐ Fail | |
| Earth continuity: door panels to frame (< 0.1 Ω) | ☐ Pass ☐ Fail | |
| Earth bar cross-section sizing adequate per fault current rating | ☐ Pass ☐ Fail | |
| Double-earthing of CT secondary circuits verified (one point only) | ☐ Pass ☐ Fail | |
| Danger / Warning labels affixed (IEC 60417 symbols) | ☐ Pass ☐ Fail | |
| Safety discharge notice posted on panel door | ☐ Pass ☐ Fail | |
| Padlock provision on main isolator / incomer verified | ☐ Pass ☐ Fail |
Checklist
Conclusion
Upon satisfactory completion of all inspections and tests, and closure of all category the FAT is deemed complete.
The following authorised signatories confirm that the capacitor bank assembly has been inspected and tested in accordance with the requirements of this checklist and is approved for dispatch.
FAT Result: ☐ Accepted ☐Accepted With Conditions ☐ Rejected
 Checklist includes visual inspection, wiring verification, insulation resistance test, capacitance measurement, reactor checks, protection tests, control logic verification and document review to ensure design, safety and performance before shipment.){kind=link}