Electrical Safety Guide for Solar & Generator Installations | PES Supply

Electrical Safety Guide for Solar & Generator Installations

Essential safety practices for DIY and professional electrical work

Personal Protective Equipment (PPE)

  • Insulated gloves: Rated for the voltage you're working with (Class 0 for up to 1000V)
  • Safety glasses: ANSI Z87.1 rated
  • Dielectric boots: Non-conductive footwear
  • Arc flash suit: For commercial/high-energy systems
  • Hard hat: For rooftop work
  • Fall protection: Harness and lanyard for roof work

Lockout/Tagout (LOTO) Procedure

  1. Identify all energy sources (grid, solar, battery, generator)
  2. Notify all affected personnel
  3. Shut down and isolate each energy source
  4. Apply lockout devices to disconnects
  5. Verify zero voltage with a multimeter
  6. Tag each lock with name, date, and reason
  7. Remove locks only after work is complete

Solar Installation Safety

DC Hazards

Solar panels produce DC voltage whenever exposed to light. Even a single 450W panel can produce 40-50V DC — enough to be dangerous. Always:

  • Cover panels with opaque material during wiring
  • Use MC4 connectors — never cut or splice PV wire
  • Install DC disconnect switch before inverter
  • Verify polarity before connecting strings
  • Use arc-fault circuit interruption (AFCI) as required by NEC 690.11

Battery Safety

Battery Type Main Hazard Ventilation Fire Suppression
LiFePO4 (LFP) Thermal runaway (rare) Recommended Class D / Water
NMC Li-ion Thermal runaway Required Class D only
AGM/Lead-Acid Hydrogen gas Required Class B/C

Generator Installation Safety

  • Transfer switch required: Never backfeed through a dryer outlet — it can kill utility workers
  • Clearances: Maintain 5 ft from openings and 18 inches from combustible walls
  • Exhaust direction: Direct away from windows and intakes
  • Fuel storage: Store gasoline in approved containers, away from ignition sources
  • Carbon monoxide: Install CO detectors near sleeping areas
  • GFCI protection: Required on all portable generator receptacles

NEC Code Requirements for Solar (NEC 690)

Requirement NEC Section Details
DC disconnect 690.13 Means to disconnect all ungrounded conductors
AC disconnect 690.15 Disconnecting means for inverter output
Rapid shutdown 690.12 Reduce PV system voltage to 80V within 30 seconds
Ground fault protection 690.41 Ground-fault detection and interruption
Arc-fault protection 690.11 DC arc-fault circuit interrupter required
Wire sizing 690.8 125% of short-circuit current

Emergency Procedures

If Someone Is Being Shocked:

  1. Do NOT touch the person directly
  2. Turn off the power source immediately
  3. If you can't turn off power, use a non-conductive object (wood, plastic) to separate them
  4. Call 911 immediately
  5. Begin CPR if not breathing

If a Battery Catches Fire:

  1. Evacuate the area immediately
  2. Call 911 — mention lithium battery fire
  3. Do NOT use water on NMC batteries (can cause explosion)
  4. LiFePO4 (LFP) batteries can be doused with water
  5. Do not re-enter until cleared by fire department