Apa yang Perlu Anda Ketahui Tentang Kegagalan Saklar Beban

Hai, saya Blue — telah bekerja sebagai jurutera elektrik selama lebih dari 20 tahun sekarang.
Saya telah menghabiskan sebahagian besar kerjaya saya merancang pemutus litar, mengurus transformator, dan membantu syarikat-syarikat tenaga menyelesaikan pelbagai cabaran sistem elektrik.

Hari ini, seorang rakan dari Asia Tenggara bertanya kepada saya:

"Apakah kerosakan biasa pada pemutus beban?"

Soalan yang bagus! Jadi mari kita pecahkan dalam istilah mudah — tiada jargon mewah, hanya perkara dunia nyata yang anda mungkin lihat di tempat kerja atau semasa penyelenggaraan.

Pertama, Apakah Pemutus Beban?

Sebelum kita bercakap tentang masalah, mari kita ulangi dengan cepat apa itu pemutus beban.

Pemutus beban adalah seperti saklar on/off berat yang digunakan dalam sistem voltan sederhana (seperti grid 10kV, 20kV). Ia boleh membuat dan memutus arus operasi normal, tetapi bukan arus kerosakan — itulah tugas pemutus litar.

Jadi anggap ia sebagai "pemain tengah" antara saklar biasa dan pemutus litar penuh. Ia lebih mudah, lebih murah, dan sering digunakan dalam rangkaian pengedaran, terutamanya di tempat-tempat di mana koordinasi perlindungan tidak terlalu rumit.

Sekarang, Mari Kita Bincangkan Kerosakan Paling Biasa

Dalam tahun-tahun kerja lapangan dan pemecahan masalah, saya telah melihat isu-isu ini muncul lagi dan lagi. Berikut adalah senarai yang paling biasa:

1. Gagal Menutup atau Membuka dengan Betul

Ini sangat biasa, terutamanya dalam peralatan lama.

Sometimes the switch won’t close even when you press the button.

Atau ia menutup, tetapi kemudian terbuka segera.

Bisa juga tersangkut dalam kedudukan tertutup dan enggan dibuka.

Mengapa ini berlaku?

Bahagian mekanikal menjadi aus seiring masa — hubungan tersangkut, spring lemah, kait tidak sejajar.

Litar kawalan mungkin mempunyai wayar longgar atau reley hangus.

Sometimes the motor operator (if electrically operated) fails.

Contoh nyata:

Saya pernah bekerja di satu tapak di mana pemutus beban tidak dapat ditutup kerana sekrup kecil telah jatuh ke dalam mekanisme dan menyangkut pergerakan. Mengambil masa 2 jam untuk mencarinya!

2. Overheating or Burning Smell

If you smell something burning near a load switch panel, don’t ignore it.

Overheating usually happens at the contacts or terminal connections.

Can lead to insulation damage, melting parts, or even fire if not fixed early.

Causes:

Loose cable connections — high resistance = heat.

Contacts getting old or pitted — bad contact surface.

Excessive current flow beyond rated capacity (overloading).

Tip: Always check the temperature regularly using infrared thermography. If a connection is more than 10–15°C hotter than others, investigate ASAP.

3. Arcing or Flashover During Operation

You hear a loud pop, maybe even see sparks — that’s arcing.

Happens mostly during opening/closing operations.

Dangerous, can damage components or cause injury.

Common reasons:

Main contacts worn out — gaps not maintained properly.

Dust or moisture inside the chamber — lowers insulation level.

Operating under load when it shouldn’t be (e.g., switching off a large motor without a circuit breaker upstream).

Note: Load switches are not meant to interrupt fault currents, only normal load currents. If you’re trying to cut through a short-circuit current, expect trouble.

4. Mechanical Wear and Tear

Load switches are mechanical devices. They move parts, so they wear out eventually.

Bearings, gears, and levers all degrade over time.

Especially true in environments with dust, salt spray, or extreme temperatures.

Prevention tip: Regular preventive maintenance (PM) is key. Lubricate moving parts, inspect linkages, and replace worn-out components before they fail.

5. Control Circuit Failures

The control side is just as important as the main circuit.

Indicator lights stop working.

Remote operation fails.

Local buttons don’t respond.

Typical causes:

Blown fuses in the control circuit.

Corroded terminals or broken wires.

PLC or RTU communication errors (in automated systems).

Quick fix idea: Use a multimeter to trace voltage drop and continuity. Start simple — check fuses first.

6. Moisture and Corrosion Inside the Enclosure

Especially common in coastal areas or humid climates.

Moisture gets into the switchgear cabinet.

Causes rust, corrosion, and reduced insulation levels.

Symptoms:

Tripping for no apparent reason.

Arcing even under light load.

Bad smell or condensation visible inside the box.

Solution: Make sure the enclosure has proper sealing and desiccant packs. In tropical areas, consider adding space heaters or dehumidifiers.

7. Wrong Operation by Personnel

Human error is still one of the biggest causes of failures.

Someone tries to open the switch under heavy load.

Or operates the switch without checking interlocks.

Even worse — someone forgets to lock out/tag out before maintenance.

Lesson learned: Training matters. Clear labeling helps. And always follow safety procedures.

Final Thoughts

Like any electrical equipment, load switches aren’t perfect. But with good design, regular maintenance, and proper operation, most of these faults can be avoided or caught early.

As someone who’s been in the field for over two decades, my advice is:

“Don’t wait for a failure to remind you that maintenance is important.”

If you're dealing with a faulty load switch and want help troubleshooting or choosing replacements, feel free to reach out. Happy to share more stories (and some war scars) from the field.

Stay safe, and keep the lights on!

— Blue