ESE Lightning Arresters that protect a whole site from a single mast
Early Streamer Emission air terminals tested to NF C 17-102:2011 with ΔT 30, 45 and 60 µs, giving protection radii up to 107 m at Level IV. Stainless-steel construction, no power supply, with masts, down conductors, strike counters and earthing supplied as one certified system by LPES International.
Get a QuoteTalk to an EngineerWhat is an ESE lightning arrester?
ESE lightning arrester vs Franklin rod / mesh system
| ESE lightning arrester | Franklin rod / mesh (IEC 62305-3) | |
|---|---|---|
| Governing standard | NF C 17-102:2011, UNE 21186 | IEC 62305-3, IS/IEC 62305-3 |
| Coverage per terminal | Radius 40–107 m (Level IV, ΔT 60 µs, 5 m mast) | Rolling sphere / protective angle from each rod; mesh spacing 5–20 m |
| Number of terminals for a 100 m × 100 m plant | 1–2 masts | Dozens of rods or a full roof mesh |
| Down conductors | 1 per terminal (2 if height above 28 m) | One every 10–25 m of perimeter |
| Visual impact / roof penetration | Minimal | Extensive on large roofs |
| Acceptance | Accepted in India, Europe (FR, ES, PT), Middle East, Africa; not in IEC 62305 or NFPA 780 | Universal |
| Best for | Open sites, plants, solar, tanks, stadiums, heritage buildings, tall masts | Buildings where a mesh can be laid, hazardous areas requiring IEC 62305 compliance |
Protection radius Rp per NF C 17-102 Annex: Rp = √(2rh − h² + ΔL(2r + ΔL)) where r = 20/30/45/60 m for Levels I–IV, h = height above the protected surface (h ≥ 5 m) and ΔL = ΔT × 10⁶ m/s.
ESE lightning arrester range from LPES
LPES ESE ΔT 30 µs
Radius up to 79 m (Level IV, 5 m mast). For warehouses, factories and buildings up to 60 m across.
View ΔT 30 models →LPES ESE ΔT 45 µs
Radius up to 93 m at Level IV, 63 m at Level I. For plants, campuses and solar blocks.
View ΔT 45 models →LPES ESE ΔT 60 µs
Radius up to 107 m at Level IV, 79 m at Level I. For refineries, tank farms, stadiums and large open sites.
View ΔT 60 models →Masts, conductors and counters
GI and FRP masts 3–10 m, copper and aluminium down conductors, lightning strike counters, earthing kits.
View the full LPS range →How to select and install an ESE lightning arrester
1. Fix the protection level first
NF C 17-102 uses four levels (I to IV) with rolling-sphere radii of 20, 30, 45 and 60 m. Level I is for hazardous-area plants, hospitals and data centres; Level II for industrial plants and telecom; Level III–IV for warehouses, commercial and residential. Run the LPES risk assessment (IEC 62305-2 / IS 3043) to find the level rather than guessing — the radius at Level I is about 25 % smaller than at Level IV for the same terminal.
2. Choose ΔT and mast height for the footprint
| ΔT | Rp at Level I (h = 5 m) | Rp at Level IV (h = 5 m) |
|---|---|---|
| 30 µs | 48 m | 79 m |
| 45 µs | 63 m | 93 m |
| 60 µs | 79 m | 107 m |
The terminal tip must be at least 2 m above the highest point it protects, and 5 m of height is the minimum for the tabulated radius. Beyond 5 m the radius grows slowly; a taller mast is mostly about clearing the roof equipment, not coverage.
3. Route the down conductor
One down conductor per terminal (two if the structure is over 28 m), 50 mm² copper or 70 mm² aluminium, routed as straight and as short as possible with bends of at least 20 cm radius, held with holders every metre, and a test joint 2 m above ground. Keep it 1 m or more from power cables and gas lines. Fit the lightning strike counter above the test joint.
4. Build the earth termination
Each down conductor ends in its own earth electrode system of resistance below 10 Ω: typically three copper bonded rods in a triangle or a crow's-foot of three 7 m tapes, with earth enhancement compound in high-resistivity ground. Bond the LPS earth to the building main earthing terminal.
5. Add the SPDs
An ESE system deals with the direct strike; it does nothing about the current that flows into the building's wiring. Every ESE installation needs Type 1+2 SPDs on the main LT panel and Type 2 SPDs downstream, plus telecom and signal SPDs.
6. Inspect annually and after every recorded strike
Check the terminal, conductor continuity, joints and earth resistance every year and whenever the strike counter increments. LPES ESE terminals have no consumable parts and no power supply, so the inspection is mechanical and electrical only.
Limitations and trade-offs
ESE terminals are not recognised in IEC 62305-3, IS/IEC 62305-3 or NFPA 780 — if the project specification, insurer or statutory authority requires IEC 62305 compliance (common in oil and gas, defence and some multinational plants), a conventional rod-and-mesh system is the only compliant choice, and LPES supplies that too. The laboratory-tested ΔT does not guarantee the full tabulated radius in every storm; NF C 17-102 itself requires the earthing and SPD parts of the system to be complete before the terminal is credited. And ESE terminals must never be installed without a down conductor and dedicated earth — a terminal bonded only to the building rebar is a hazard, not protection.
Datasheets, certificates and CAD
Every LPES product ships with a datasheet, test report reference and declaration of conformity. Download the current catalogue and product datasheets from the Downloads library, or ask for the CAD block and single-line drawing for your panel from the RFQ form below.
Frequently asked questions
How does an ESE lightning arrester work?
It uses the electric field of the approaching storm to launch an upward streamer earlier than a passive rod would, by a tested advance time ΔT. The earlier streamer meets the downward leader higher up, so one terminal intercepts strikes over a larger radius. The strike current is then carried to earth by a normal down conductor and earth electrode.
What is the protection radius of an ESE lightning arrester?
Between 40 m and 107 m depending on the terminal's ΔT (30, 45 or 60 µs), the protection level (I–IV) and the height of the tip above the protected surface (minimum 5 m for the tabulated values). A ΔT 60 µs terminal on a 5 m mast covers 79 m at Level I and 107 m at Level IV per NF C 17-102:2011.
Is an ESE lightning arrester approved in India?
There is no Indian standard for ESE terminals; IS/IEC 62305 covers conventional systems only. ESE systems are widely installed in India under NF C 17-102:2011 and accepted by most consultants, PSUs and insurers for open sites, plants, solar farms and buildings, but check the project specification — oil and gas, defence and some multinational sites require IEC 62305 compliance.
What is the difference between ΔT 30, 45 and 60 µs?
ΔT is the streamer advance time measured in the high-voltage laboratory test of NF C 17-102. A larger ΔT gives a larger protection radius: at Level IV on a 5 m mast, 79 m (ΔT 30), 93 m (ΔT 45) and 107 m (ΔT 60).
Does an ESE terminal need a power supply or battery?
No. LPES ESE terminals are entirely passive, stainless-steel devices energised by the storm's own electric field. There are no batteries, electronics or consumables to maintain.
Do I still need surge protection devices with an ESE system?
Yes, always. The ESE system intercepts the direct strike; the current it discharges raises the earth potential and induces surges in every cable on site. Type 1+2 SPDs at the main panel, Type 2 at sub-panels and signal SPDs on data and telecom lines are part of the NF C 17-102 system, not an option.
How many down conductors does an ESE arrester need?
One per terminal for structures up to 28 m, two for taller structures, each 50 mm² copper or 70 mm² aluminium with a test joint and its own earth electrode of less than 10 Ω.
How often should an ESE lightning protection system be inspected?
At least once a year, ideally before the monsoon, and after every strike recorded on the lightning strike counter: visual check of the terminal and mast, continuity of the down conductor and joints, and a measured earth resistance at each test joint.
Related pages
Want the ESE mast count and layout for your site?
Send the site plan and the protection level (or let LPES run the IEC 62305-2 risk assessment); we return the terminal selection, mast positions, down-conductor routing, earthing and SPD BOQ within two working days.
