Undervoltage trip on bus-tie opening
A replacement breaker's UVT coil did not match. A first fix failed and pointed to the switching sequence; a 1 s off-delay timer cured it and the drawing was updated.
MCCB Kept Tripping for 1 Year
ProbeLemEngineering dossier
Lemuel Q. Regio, REE
Registered Electrical Engineer since 2008. Six years of HV/MV testing and commissioning, then ten years at sea as a marine ETO. Test plans, test reports, work methods and costing, re-typeset from my own work files. In the reports, client staff names and client asset serials are blacked out; prices withheld.
18 yrsin the electrical trade, never out of it
6 yrsHV/MV testing and commissioning, up to the 34.5 kV class
10 yrsmarine ETO, including a 6.6 kV, 60 Hz ship plant
58client and project folders in my testing archive
Career timeline
Construction, testing, sea.
- 2008BSEE, Technological University of the Philippines; Registered Electrical Engineer (Oct 2008)
- 2008 to 2009Project Electrical and QA/QC Engineer, United Power Systems Philippines
- 2009 to 2016Technical Services Engineer, United Services Corporation: MV/HV testing and commissioning, costing, crews, close-out
- 2016ETO training (STCW A-III/6); electrician cadet
- 2017 to 2022Electrician and ETO: 6.6 kV plant, PLC, VFD and Modbus integration work
- 2022 to nowTravelling fleet ETO, chemical tankers, hazardous areas
- 2023 to nowFounder, ProbeLem: fault-finding docu-vlog and training for new ETOs
Marine ETO dossier, 2016 to now
Ten years as a marine ETO.
- Often the only electrical person on board
- 6.6 kV, 60 Hz plant and 6.6 kV bow thruster on an earlier vessel; 440 V and 380 V fleets since
- Switchboards, generators and protection, VFDs, PLCs, fire and gas systems
- Hazardous areas on chemical tankers; permits and isolation every day
- Travelling fleet ETO since 2022: faults beyond the crew, electrical compliance audits
How I find faults
The Probing Loop: identify the real mechanism, probe on paper then with a test that can fail, steer by the result, seal with the fix, the record and the updated drawing.
Main engine would not start, berth needed
Found and repaired broken cylinder-2 wiring, then proved the start chain stage by stage on turning gear. That sent the search to the pilot valves; the start test passed.
Main Engine Starting Failure, Part 2Past role, 2009 to 2016
Testing & Commissioning Electrical Engineer.
Technical Services Engineer, United Services Corporation, Manila. MV/HV testing and commissioning up to the 34.5 kV class, costing and proposals, crews, reports and close-out.
Scope of work, matched to the evidence
| Scope | What the record shows |
|---|---|
| HV/MV testing and commissioning | Seven 34.5/6.6 kV, 3 MVA power transformers (Philippine Arena); a 38 kV, 2000 A outdoor vacuum breaker on a 34.5 kV system |
| Protection relay testing | 16 SEPAM relays by secondary injection: phase and earth-fault overcurrent, overvoltage, over- and under-frequency |
| OMICRON and Megger test sets | CPC 100 with CP TD1; Megger 120 kV DC set and OTS60PB oil tester, named on the reports; breaker timing on a CIBANO 500 by our testing subcontractor |
| ITPs and ITRs | An ITP I prepared (2011); a test plan from my approved procedure; signed, serialised reports quoting the acceptance limit |
| Risk assessment and work methods | Lift beneath energised lines: hazards, controls, permits, lockout, lifting plan and a written stop rule |
| SF6 switchgear | ABB SafePlus SF6-insulated ring main unit, 13.8 kV, 630 A (2012): IR, functional and fault-indicator checks, released for energisation |
| Costing and commercial | Bottom-up estimates, signed proposals, proposed versus actual review |
What I tested, and with what
- Transformers: IR and PI, turns ratio on all taps, winding resistance, excitation current, PF/tan delta, oil DBV
- CTs: ratio, polarity and phase angle, up to 800 A primary
- Vacuum breakers: IR, contact resistance, HV withstand; timing results reviewed
- Protection relays: secondary injection, SEPAM 40 and G87
- Earthing, NER resistance, thermography, LV and MV switchboards
- Kit: OMICRON CPC 100, CP TD1, CP CU1; Megger 120 kV DC; Megger OTS60PB; Fluke 1550B
Philippine Arena, for Schneider Electric
16PIX12 7.2 kV switchgear sections
7MV power transformers, 34.5/6.6 kV
116.6/0.38 kV distribution transformers
- Tested and commissioned switchgear, vacuum breakers, transformers and protection
- Prepared the planned versus actual schedule and delay assessment
- Prepared the switchgear and transformer proposals
The inspection and test plan I prepared (2011)
ITP TIPI-ITP-001-11: 13.8 kV plant substations at a semiconductor manufacturer, with USC as testing subcontractor to the main electrical contractor. Sign-off columns for client, USC and others. Tied to work method WMS-001-11: scope, crew of four, test equipment (CPC 100 with CP TD1, Fluke sets) and a HIRARC risk appendix.
| Task | Conformance criteria | Verification record |
|---|---|---|
| Facility and equipment preparation | Verify proper connection | Visual and schematic inspection |
| Calibration of circuit breaker protective relays | Conformance to primary calibrating equipment | Visual and schematic inspection |
| Calibration of over- and undervoltage relays | Conformance to primary calibrating equipment | Visual and schematic inspection |
| Contact resistance on circuit breakers (normal and emergency) | Manufacturer's published data | Visual and schematic inspection |
| Transformer winding insulation integrity | Manufacturer's published data | Left blank on the original |
| Transformer turns ratio | Manufacturer's published data | Left blank on the original |
| Transformer IR with polarisation index | Manufacturer's published data | Left blank on the original |
| Lightning arrester insulation power factor | Manufacturer's published data | Left blank on the original |
Transformer test plan (2013)
| Activity | Method | Acceptance |
|---|---|---|
| Visual and mechanical | Nameplate against drawings and specification; torque checks; earthing; accessories | Checklist complete |
| IR and polarisation index | 1 and 10 min, HV-LV, HV-earth, LV-earth; corrected to 20 °C | NETA ATS Table 100.5; PI > 1.0 |
| Turns ratio, every tap | Three-phase equivalent per tap, against nameplate | Error ≤ 0.5% |
| Winding resistance, every tap | DC per phase, both windings; temperature recorded | Within 5% of factory or sister unit |
| Power factor and capacitance | Tap at neutral; temperature-corrected | 0.5% HV-LV, 1.0% to earth |
| Excitation current | Same voltage each phase, against factory and sister units | Two outer phases similar, middle lower |
| Oil dielectric breakdown | 2.5 mm gap, 3 min settling, 3 kV/s, five fillings | Not below 30 kV |
Transformer Testing and Commissioning Procedures, Rev.1, Sept 2013. Prepared by L.Q. Regio. Scope: 7 × 34.5/6.6 kV and 11 × 6.6/0.38 kV units.
Transformer test report, unit 1 of 7
0.11%worst turns-ratio error over 5 taps (limit 0.5%)
0.4%HV winding resistance balance on every tap
0.57%highest PF at 20 °C (HV-earth)
| Insulation resistance | 1 min | 10 min | PI |
|---|---|---|---|
| HV-LV, 5 kV | 15.2 GΩ | 113 GΩ | 7.43 |
| HV-earth, 5 kV | 5.39 GΩ | 10.0 GΩ | 1.85 |
| LV-earth, 2.5 kV | 6.00 GΩ | 14.9 GΩ | 2.48 |
| Power factor | C (nF) | PF @ 20 °C |
|---|---|---|
| HV-LV, 5 kV | 2.651 | 0.23% |
| HV-earth, 5 kV | 1.330 | 0.57% |
| LV-earth, 2.5 kV | 3.819 | 0.47% |
Excitation at 5 kV: 11.16 / 4.14 / 11.05 mA (A / B / C). Oil breakdown: five fillings, 27.0 to 42.3 kV, average 35.5 kV; one filling below the report's 30 kV line. All instruments serialised. 3 MVA, 34.5/6.6 kV, Dyn11. USC-TR-001-13, 11 Dec 2013. Tested by L.Q. Regio and a co-tester.
Protection relay testing: 16 SEPAM relays
- Review the settings sheet and schematic; isolate trip outputs
- Secondary injection at 150%, 300% and instantaneous
- Check overvoltage and frequency elements and indications
- Record trip times on the controlled form
- Restore links and sign off
| Feeder 01, SEPAM 40 | 150% I (A) | t (s) | 150% Ie (A) | t (s) | 300% I (A) | t (s) | Inst. I (A) | t (s) |
|---|---|---|---|---|---|---|---|---|
| Phase A | 4.8 | 7.826 | 1.425 | 3.652 | 9.6 | 1.887 | 60 | 0.240 |
| Phase B | 4.8 | 7.842 | 1.425 | 3.724 | 9.6 | 1.862 | 60 | 0.232 |
| Phase C | 4.8 | 7.816 | 1.425 | 3.760 | 9.6 | 1.926 | 60 | 0.264 |
| Generator 01, SEPAM G87 | Injected | Trip time (s) |
|---|---|---|
| Overvoltage, A / B / C | 140 V | 1.005 / 1.005 / 0.993 |
| Overfrequency | 62 Hz | 1.255 |
| Underfrequency | 59 Hz | 1.252 |
7.73 to 7.90 s trip band at 150% and 1.83 to 1.93 s at 300% across all 16 relays (8 × SEPAM 40 feeder, 8 × SEPAM G87 generator). HVX vacuum breaker, Feeder 01: IR at 2.5 kV 151 to 421 GΩ (limit 2 GΩ); contact resistance at 400 A 32.60 to 33.23 µΩ, spread 1.9%; one sheet per breaker, 16 breakers. Relay Functional Test Report, Philippine Arena, 25 to 27 March 2014. Tested by L.Q. Regio. I test relays against the settings issued for the job; I have not calculated settings.
The reports as issued, Philippine Arena
Page 1 of each signed report. Client asset serials and other people's names blacked out.
Ports, plants and island networks
| Site | Scope |
|---|---|
| ICTSI Berths 5 and 6 (Cummins) | PIX12 7.2 kV switchgear, HVX breakers, SEPAM relays; 3 MVA transformer, NER, 4 × 2.28 MVA 4.16 kV gensets |
| Texas Instruments, Baguio | Eight 13.8 kV substations tested in 2011, as testing subcontractor to the main electrical contractor |
| Balesin Island (Alphaland) | 13.8 kV island network: 13 ABB distribution transformers; ABB SafePlus SF6-insulated ring main unit, 630 A (2012) |
| MATES and Tong Hsing | 34.5 kV class transformers: ratio, winding resistance, PF, oil DBV, IR scans |
Lafarge Teresa 34.5 kV substation
- Replaced a Siemens dead-tank oil breaker with a Schneider VOX 38 kV, 2000 A vacuum breaker
- 34.5 kV control and protection panel (NEMA 12): fabricated, installed, tested and commissioned by our team
- SEPAM 40 protection; settings keyed in and tested
- Wrote the A-frame breaker positioning procedure: survey, permits, roles, stop rules
- Closed out with as-builts, completion certificate and warranty certificate
| Breaker test, 38 kV vacuum breaker | Result |
|---|---|
| IR at 5 kV, closed and open | 27.9 to 165 GΩ, balanced across phases |
| DC withstand, 70 kV, 60 s | 14.1 / 17.9 / 17.7 µA, held |
| Contact resistance at 100 A | 47.23 / 46.55 / 47.55 µΩ (OEM as-new limit 52 µΩ) |
| Timing: open / close, O-C-O sequence | 43.7 to 43.8 ms / 55.5 to 56.1 ms; pole spread 0.1 ms opening, 0.6 ms closing |
| Minimum pick-up, ramp to 125 V | Trip coil 35 V, close coil 60 V |
Timing and pick-up were run by our testing subcontractor on an OMICRON CIBANO 500 and carried into our signed report. IR, withstand and contact resistance are our own tests (CPC 100, Megger 120 kV DC, Fluke 1550B). 38 kV, 2000 A outdoor dead-tank breaker. Test report USC-TR-001-15, 21 to 22 May 2015, witnessed by the client. Tested by L.Q. Regio and a co-tester.
Work method: a lift beneath live lines
- SurveySafe distance to live lines, terrain, load, clearances; tabletop walkthrough
- PermitsWork and lifting permits; lifting plan with equipment positions
- Toolbox talkScope, timeline, assignments, cautions
- IsolateBarricade, signs, watchman; a padlock and PPE for every worker
- LiftA-frame hook height set so the lift never breaches the safe distance
- Set and earthLevel base frame, final torque; earthing tied to the grid; fall-of-potential test
“For any hazard or irregularities being observed, stop and notify the supervisor, leadman and safety officer to check and resolve prior to go on.”Stop rule, in the method
No one under a suspended load. Safety officer on site for the whole lift. Arc flash from approach to live lines listed and controlled. Positioning and installation procedure using A-frame, 6 May 2015. Prepared by L.Q. Regio, approved by the General Manager.
Leading crews on site
- Planned crews by work front: engineers, foremen, electricians and helpers
- Wrote work method statements (BSP, AMS Asia transformer testing, Lafarge A-frame)
- Ran toolbox talks; worked under client permits to work
- Coordinated shutdowns in phases with the client
- Tracked progress against plan and reported weekly to management
From enquiry to close-out
- Enquirytechnical evaluation
- Surveywork plan checklist
- CostingBOQ, unit price analysis
- Proposalquotation via Sales
- ContractPO or services agreement
- Mobilisetools, consumables, calibrated kit
- Executepermits, daily reports
- Test15 controlled report forms
- Accepttest certificate, acceptance
- Close outcompletion, warranty, billing
How I costed a T&C job
| Cost head | How it is built |
|---|---|
| Proposal summary | One pay item per equipment and test package |
| Unit price analysis | Labour = headcount × rate × hours; overtime factor 1.25 |
| Equipment | Test-set charge from cost recovery over utilisation |
| Materials and logistics | Consumables, transport, fuel and tolls, accommodation, permits |
| Overhead, contingency, profit | Markup versus margin, applied deliberately |
Bids and proposals I prepared include 115 kV and 69 kV substation T&C bids, a substation T&C estimate, the Lafarge Teresa proposal (Rev 1, with deductive and additive items), and the Philippine Arena switchgear and transformer proposals. Client prices withheld.
0%testing and commissioning, actual versus estimate
+33.5%heavy lift: two crane bookings
−4.5%final value against the proposal
Proposed versus actual: the transformer package
| Where the price went | Share of direct cost |
|---|---|
| Delivery and lift | 53% |
| Testing and commissioning | 36% |
| Preliminaries | 11% |
| Line | Actual vs proposal |
|---|---|
| In-land transport | −14.0% |
| Customs clearing (not needed) | −100% |
| Total direct cost | +5.8% |
| Overhead and profit | −19.9% |
Transformer package, Philippine Arena: 30 working days, 240 regular plus 76 overtime hours. On a heavy-equipment job the lift, not the testing, carries most of the cost and the risk. I priced testing from crew-hours I knew. Peso values withheld.
Beyond the test set
Documentation, training, leadership.
Documentation
Methods, test plans, reports and handovers that others can follow. Excel estimating; Word and PowerPoint.
Training (ProbeLem, since 2023)
I write, film and edit short technical videos on real fault-finding for junior electro-technical officers. It keeps my explanations clear for clients and new technicians.
Leadership at USC
Supervised crews of engineers, foremen and technicians; wrote the department's job descriptions and technical tests; ran in-house training on transformer maintenance and testing.
How I use AI
One written brief per AI agent; independent views from different models, then one synthesis; a model from a different vendor checks the work before I see it. AI drafts; I verify every number against the source and sign. Client data stays in approved tools.
Education and recognition
Qualifications.
| Year | Award or qualification |
|---|---|
| 2008 | Registered Electrical Engineer, Professional Regulation Commission |
| 2008 | Team Champion, 5th IIEE national Philippine Electrical Code quiz show |
| 2008 | Special Award in Science and Technology, Technological University of the Philippines |
| 2008 | B.S. Electrical Engineering, Technological University of the Philippines |
| 2002 to 2005 | DOST-SEI science and technology scholar; Diploma in Electrical Engineering Technology |
| 2002 | High school class valedictorian; Philippine Senate Gold Medal for Academic Excellence; Eagle Scout |
Held
- REE (PRC), 2008; IIEE member
- STCW ETO certificate of competency
- FSE high and low voltage refresher, every year 2022 to 2026
- EX Basic hazardous areas, Sep 2026
- Certified BERDE Professional (green building)
Ready to train on
- OMICRON CMC 356 with Test Universe; CT Analyzer
- Relay settings software
- Offline partial discharge and VLF cable testing
- SF6 gas handling; SCADA
- Site inductions, HV switching training and authorisation
Originals of every record on this page are available on request through the contact links on probelem.com.