Protection Panel Testing for Panel Builders
A protection panel leaves the workshop with a relay configuration, a wiring scheme, a trip circuit and a set of interlocking logic. The factory acceptance test has to prove all four before the panel ships. A relay that passes a standalone test can still fail on site because the CT circuit is wired to the wrong polarity, the trip output is mapped to the wrong terminal, or the interlock logic was never exercised as a sequence.
Panel builders and switchgear OEMs need a test set that is fast enough for repeat production, flexible enough for several relay brands, and documented well enough to hand to the end customer. This page describes the FAT scope and where the VAE-430 and VAE-660 fit.
What a panel FAT has to prove
| Item | What is checked | Typical method |
|---|---|---|
| Relay configuration | Model, firmware, settings group and logic match the approved scheme | Settings file comparison and a functional check of each enabled element |
| CT and PT circuits | Ratio, polarity, burden and phase sequence | Secondary injection through the panel terminals; current and voltage readings compared with the injected values |
| Trip and close circuits | Trip coil, close coil, trip-circuit supervision and breaker-fail logic | Trip output driven by the test set; coil current and breaker status monitored |
| Interlocking | Breaker, earthing switch and busbar interlocks prevent unsafe states | Status inputs simulated; close/trip outputs checked against the interlock table |
| Annunciation and SCADA mapping | Alarms, event records and remote signals map to the correct points | Force each input and confirm the corresponding output or event |
| ATS and control logic | Transfer sequence, generator start, load shedding and inhibit | Voltage and status simulation; sequence timed through the binary inputs |
A repeatable FAT workflow
- Incoming inspection. Confirm the panel matches the drawing, the relay model and firmware are correct, and the wiring is complete before applying any test voltage.
- Relay configuration. Load the approved settings file, compare it with the scheme, and record the checksum or file version.
- Point-to-point wiring check. Inject at the panel terminals and confirm the relay reads the correct quantity, phase and polarity. This catches CT/PT wiring errors before functional tests.
- Functional test. Exercise each protection element at its boundary: pickup, drop-out, time delay and characteristic curve.
- Trip test. Drive the trip output and confirm the breaker or trip relay operates, the correct pole or coil is energized, and the event record matches.
- Report. Store the test result per relay, the settings file, the wiring check and the non-conformance log. The customer’s handover package usually asks for all four.
Test objects and recommended model
| Panel type | What to prove | Injection and I/O | Recommended |
|---|---|---|---|
| Feeder protection panel | 50/51, 51N, 27/59, 81, trip and alarm outputs | Three currents, three voltages, binary I/O | VAE-430 |
| Transformer protection panel | 87T differential, 63, 24, backup overcurrent | Six currents and voltages for 87T | VAE-660 |
| Generator protection panel | 32, 40, 46, 51V, 64G, 81, 87G | Six currents and voltages for 87G | VAE-660 |
| Busbar and main-tie panel | 87B, interlocking, transfer logic | Three or six currents, status I/O | VAE-430; VAE-660 for 87B |
| ATS / control panel | Transfer sequence, generator start, load shedding, inhibit | Two three-phase voltage sets, binary I/O | VAE-660 |
| Marine / offshore panel | Generator protection, preferential trip, class documentation | Six currents and voltages, 8/8 I/O | VAE-660 |
Why a portable secondary-injection set
- Several relay brands, one test set. The VAE series is brand-agnostic: it injects the quantities the relay expects and reads the outputs. Test templates are organized per relay type, not per manufacturer.
- Enough I/O for a panel, not just a relay. The VAE-430 has 8 binary inputs and 4 outputs; the VAE-660 has 8 and 8. That is enough to simulate breaker status, interlock feedback, ATS status and trip outputs in one sequence.
- Repeatable documentation. Results are stored per test point, so the FAT report can be produced without retyping readings from a bench meter.
- Portable between bays. At 18 kg and 21 kg, the sets can be moved from one panel to the next without a trolley or a dedicated test bay.
VAE-430 or VAE-660
| Panel workload | VAE-430 | VAE-660 |
|---|---|---|
| Feeder, motor and single-ended transformer panels | Yes: 3 current, 4 voltage, 8 BI / 4 BO | Yes, with spare channels |
| Transformer or generator differential panels | No: three current channels | Yes: six current channels |
| ATS / control panels with two sources | Limited: sequential or single-source only | Yes: six voltage channels |
| High-burden electromechanical relays | Yes: 900 VA single-phase parallel output | Yes: 1000 VA single-phase output |
| Portability between bays | 18 kg | 21 kg |
What the test set does not do
This is a secondary-injection test set. It does not perform primary injection, it does not energize the switchgear bus, and it does not replace the panel’s mechanical endurance or dielectric tests. It also does not test IEC 61850 GOOSE or Sampled Values; a process-bus panel needs a dedicated IEC 61850 test set. Where the FAT specification asks for primary injection, a separate primary-injection set is required.
Frequently asked questions
Can the VAE-430 test panels with several relay brands?
Yes. The test set is brand-agnostic; it injects current and voltage and reads binary outputs. The test templates are organized by protection function and relay type, so one set can cover a mixed panel population.
Do I need six currents for every panel?
No. Feeder, motor and single-ended transformer panels need three currents. Six currents are needed for transformer differential, generator differential, busbar differential and other multi-end schemes.
Can it test the trip circuit and trip coil?
It can drive the trip output and time the breaker or trip relay operation through the binary inputs. Trip-coil current and voltage are measured with a separate meter or the panel’s own monitoring, depending on the FAT specification.
Can it produce the FAT report?
The software stores the test results per point. The report format is normally the panel builder’s own template; the test set supplies the readings and pass/fail data.
Can it test IEC 61850 panels?
Only the analog secondary-injection part. GOOSE and Sampled Values testing requires a dedicated IEC 61850 test set, which VA-TEK does not supply.