Ang Kailangan Mong Malaman Tungkol sa Mga Pagkakamali ng Load Switch

Kamusta, ako si Blue — nagtatrabaho na bilang isang electrical engineer ng mahigit 20 taon ngayon.
Nagpasya akong gumastos ng karamihan ng aking karera sa pagdisenyo ng circuit breakers, pagmamanage ng mga transformers, at pagtulong sa mga kompanya ng kuryente na lutasin ang iba't ibang hamon sa electrical system.

Ngayon, may kaibigan mula sa Timog-silangang Asya na nagsabi sa akin:

"Ano ang mga karaniwang kaputol ng load switches?"

Mahusay na tanong! Kaya't ipaliwanag natin ito sa simpleng termino — walang fancy jargon, kundi tunay na bagay na maaari mong makita sa trabaho o panahon ng maintenance.

Una, Ano Ba Talaga Ang Load Switch?

Bago nating talakayin ang mga problema, ipaalala natin muna kung ano ang load switch.

Ang load switch ay parang isang matibay na on/off switch na ginagamit sa medium-voltage systems (tulad ng 10kV, 20kV grids). Ito ay maaaring gawin at i-break ang normal operating currents, ngunit hindi fault currents — iyon ang tungkulin ng mga circuit breakers.

Kaya isipin mo ito bilang ang "gitnang tao" sa pagitan ng regular na switch at ng buong circuit breaker. Ito ay mas simple, mas murang, at madalas ginagamit sa distribution networks, lalo na sa mga lugar kung saan ang protection coordination ay hindi napakakomplikado.

Ngayon, Ipapaliwanag Namin Ang Mga Karaniwang Kaputol

Sa aking mga taon ng fieldwork at troubleshooting, nakita ko ang mga isyung ito paulit-ulit. Narito ang listahan ng mga pinaka-typical na kaputol:

1. Pagkakamali Sa Pagsara O Pagbubukas

Itong isa ay malimit, lalo na sa mga lumang kagamitan.

Minsan, hindi maglilihis ang switch kahit pumindot ka ng button.

O sasara, ngunit agad na bubukas.

Maaari ring makuha sa posisyong sarado at ayaw bumuka.

Bakit ito nangyayari?

Ang mga mekanikal na bahagi ay nababawasan ang lakas sa paglipas ng panahon — linkages na nasa huli, springs na mahina, latches na misaligned.

Ang control circuits ay maaaring may loose wires o burned relays.

Minsan, ang motor operator (kung electrically operated) ay maaaring mabigo.

Tunay na halimbawa:

Ipaglaban ko ang isang lugar kung saan ang load switch ay hindi naglilihis dahil ang isang maliit na screw ay napatulo sa mechanism at nagbabaril ng paggalaw. Iniwan namin ito ng 2 oras upang makahanap!

2. Overheating O Amoy Sunog

Kung amoy mo ang sunog malapit sa load switch panel, huwag ito igalaw.

Ang overheating ay karaniwang nangyayari sa contacts o terminal connections.

Maaring humantong sa insulation damage, melting parts, o kahit na sunog kung hindi ito na-attend early.

Dahilan:

Loose cable connections — mataas na resistance = init.

Contacts na lumang o pitted — masama ang contact surface.

Excessive current flow beyond rated capacity (overloading).

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

3. Arcing O Flashover Sa Panahon Ng Operasyon

Maririnig mo ang malakas na pop, baka pa makita ang sparks — iyon ang arcing.

Kadalasang nangyayari sa panahon ng pagbubukas o pagsasara.

Panganib, maaaring masira ang mga bahagi o maging sanhi ng injury.

Karaniwang dahilan:

Main contacts na lumang — gaps na hindi nai-maintain ng maayos.

Dust o moisture sa loob ng 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