Product Description
Delta LA303
3 or 4 Wire • Three Phase • 300VAC AC Lightning Arrestor
Delta Lightning Arrestors provide rapid‑response, high‑current surge protection for sensitive electronics and three‑phase power systems. The Delta LA Series is engineered to safely divert lightning surges up to 50,000 amps, protecting equipment from damaging voltage spikes.
The LA303 is designed for 110/208/250VAC three‑phase systems using either 3‑wire or 4‑wire service. It is ideal for commercial, industrial, and high‑demand electrical environments requiring robust surge protection across three hot legs.
Delta Arrestor Features
- Non‑conductive base prevents shock hazards in the event of failure
- Fails without producing carbon dust that could damage nearby equipment
- Always fails “clear,” allowing continued system operation
- Silicon‑based design for fast response and low conduction resistance
- Handles numerous high‑energy surges and half‑cycle spikes before failure
- Extra‑long leads for easier installation
- Includes locknut and bushing
- Available in multiple voltages and pole configurations
LA303 Specifications
| Rated Voltage | Design Type | Surge Current | Max Energy | Leads | Enclosure Rating | Dimensions |
| 110/208/250V Three Phase 3 or 4‑Wire |
Silicon Oxide Varistor | 100,000 amps | 3,000 Joules per pole | 36" #12 THHN | NEMA 4 | 4.5" H × 2.25" D |
Need help selecting the right surge protection?
We support residential, commercial, and industrial power systems—contact us anytime.
