Every solar installation in the Philippines must comply with the Philippine Electrical Code (PEC) 2017, which is aligned with the US National Electrical Code (NEC) 2014 with local amendments. Non-compliant installations are rejected by distribution utilities (Meralco, VECO, DLPC) during net metering inspection — costing the installer re-work, delays, and client trust.
| PEC Article | Topic | Key Requirement |
|---|---|---|
| Article 2.30 | Wiring Methods | All exposed DC wiring must be in conduit or listed solar cable (USE-2 or PV wire rated) |
| Article 2.50 | Grounding | All metal frames, mounting rails, and inverter enclosures must be bonded to a common grounding electrode system |
| Article 6.90 | Solar PV Systems | Dedicated article for PV systems — covers string sizing, disconnects, marking, and ground fault protection |
| Article 2.10 | Protection Devices | DC and AC overcurrent protection required at each source and load point |
| Article 3.10 | Conductors | Conductor sizing based on 125% of rated current for continuous loads (most solar circuits qualify) |
For residential solar (dwelling units), the maximum PV system voltage is limited to 600V DC under PEC 2017. This directly affects how many panels you can string in series.
A readily accessible DC disconnect must be located within sight of or integral to the inverter. The disconnect must be rated for the maximum DC voltage and current of the system.
When more than 2 strings are connected in parallel, each string must be individually fused at the combiner. This prevents backfeed current from damaging panels in a faulted string.
All grid-tied inverters sold in the Philippines must include ground fault detection and interruption (GFDI). Most modern hybrid inverters have this built in — verify before purchasing.
PEC requires warning labels at:
Tip for installers: Request a pre-inspection checklist from your local distribution utility before submission. Meralco publishes their net metering requirements on their website, and VECO/DLPC have similar documents available upon request.
Engr. Jason Morales — Founder, SolarEnergyPH