Code and safety: PEC 2017 and NEC 690 in one page
The Philippine Electrical Code follows the NEC, and its Article 6.90 is NEC 690: the solar article. Eleven rules carry most of its weight, and every one of them is a rule in the lab’s safety check. Knowing which article a finding points to is what lets an installer argue with an inspector, and what an NC-II examiner asks.
Open this lesson in the labFree, in your browser, no account needed.
How it works
| 690.7 (A1) | Maximum system voltage from the lowest expected ambient: the cold-morning Voc rule. |
| 690.8 (B1, B2) | Circuit current 125 % of Isc; conductors for 125 % of that: 1.56 × Isc. |
| 690.9 (B3, B4) | Overcurrent protection: string fuses at three or more strings; the battery circuit fused at the battery. |
| 690.12 (F4) | Rapid shutdown of rooftop conductors (jurisdiction-dependent in the Philippines). |
| 690.13, 690.15 (E4) | Disconnecting means for the array, the battery and the inverter, within sight and labelled. |
| 690.43, 690.47 (F1, F3) | Equipment grounding of frames and enclosures; the grounding electrode. |
| 705.40, UL 1741 (E2) | A grid-connected inverter must stop when the grid does: anti-islanding. |
| 706 (D) | Energy storage: listed batteries, BMS for lithium, ventilation for flooded lead-acid, disconnects. |
| 240.4 (B4) | A conductor is protected by an overcurrent device no bigger than its ampacity. |
| 210.19 note (C1) | Voltage drop: 3 % on a branch, 5 % total, as good practice. |
| 285 (F2) | Surge protective devices, with a grounding electrode to work against. |
Run the 🛡 Safety check on this hybrid bench and read the article beside each finding. PEC article numbers follow the NEC ones they mirror; verify against the current PEC edition.
Try it on the bench
- Remove the battery breaker on the bench and run the check: 690.9 and 240.4 appear with the fix.
- Wire the hybrid’s AC-OUT straight to the grid: 705.40 appears in red, with why.
Parts on the bench
- Utility grid
- Net meter
- 4 × AC breaker
- Hybrid solar inverter
- 220 V bulb
- 220 V desk fan
- 2 × Household appliance
- 4 × Solar panel
- 2 × DC breaker
- LiFePO4 battery
- Wall switch
- 2 × Wall outlet
In the course
Solar PV Systems, module “14 · Code and safety”.
More on solar pv physics
- The IV curve: Voc, Isc and the knee
- Cold mornings raise Voc; hot noons cut power
- Shading and bypass diodes: a shadow costs more than its size
- A string against the controller: the cold-morning Voc
- PWM against MPPT: the harvest, as a number
- Lead-acid against LiFePO4: usable capacity, voltage and life
- Wiring, fuses and breakers for an array: the 1.25 and 1.56 rules
- Grounding, bonding and surge protection: the two jobs of earth