Technical Specifications

Main Features and Advantages

Rugged enclosure for harsh environments: The 1LS1-4PG​ is built with a die-cast zinc housing and nitrile gasket that achieves NEMA 4. 13. and IP67 ratings, meaning it shrugs off oil mist and hydraulic leaks in stamping presses (NEMA 13), high-pressure washdown with cleaning chemicals in food & beverage packaging lines (NEMA 4/IP67), and dust/debris in agricultural and bulk material handling sites. For plants running both NA and international lines, the 4PG’s PG13.5 gland integrates directly with metric conduit runs without adapters, avoiding a common failure point where NPT-to-metric transitions loosen over vibration cycles and let contaminants in.

Snap-action contact reliability: Honeywell’s signature snap-action mechanism in the 1LS1-4PG​ delivers fast contact transfer with minimal arcing, extending electrical life to 500k full-load cycles even in inductive load applications (motor starters, solenoid valves). The SPDT 1NO+1NC configuration supports both control signaling and safety interlock loops in a single device, reducing panel component count. Repeatability holds to ±0.001″ (±0.025 mm), which is critical for CNC machine tool travel limits and automotive weld cell robot reach sensing where positional drift would cause part defects or collision risks.

Long service life & low maintenance: The 10 million mechanical cycle rating means the 1LS1-4PG​ can run for years on high-cycle applications like conveyor sortation gates, bottling line filler carriages, and palletizer travel stops without needing replacement. Even when electrical contacts eventually wear, the modular 1LS series design allows contact block replacement without swapping the entire switch, cutting maintenance downtime and spare cost.

Shared 1LS ecosystem compatibility: The 1LS1-4PG​ works with all standard 1LS series accessories: longer adjustable levers (LSZ series), roller lever tips for reduced friction on moving parts, and side-mount brackets. Plants already using other 1LS variants (1LS2 top push, 1LS3 side roller) can share spare levers and mounting hardware with the 1LS1-4PG, keeping inventory lean.

Application Field

The 1LS1-4PG​ is specified across nearly every heavy industrial sector where position sensing needs to survive harsh conditions and high cycle rates, with its PG13.5 gland making it a default choice for global OEMs exporting machinery to EU, APAC, and Middle Eastern markets.

Material handling is the largest volume use case: high-cycle conveyor systems use the 1LS1-4PG​ for belt alignment sensing, sortation gate travel limits, and palletizer carriage end stops — the 10M mechanical life holds up to 24/7 operation, and the adjustable lever lets integrators tune actuation points during commissioning without replacing hardware. Sortation hubs with washdown requirements (e.g., parcel handling with cleaning cycles) benefit from the NEMA 4 rating to avoid switch failure from spray.

Automotive and heavy manufacturing deploy the 1LS1-4PG​ for stamping press slide travel limits, weld cell robot reach interlocks, and CNC lathe/mill table end stops. The NEMA 13 oil-tight rating resists hydraulic oil and weld spatter, while ±0.025 mm repeatability ensures part dimensional consistency on precision machining lines. Many automotive OEMs standardize on the 1LS series across global plants, so the 1LS1-4PG​ (metric gland) and 1LS1-4 (NPT gland) can coexist in the same spare pool with only the gland differing.

Food & beverage applications include packaging machine rotary turret position sensing, bottling line filler carriage limits, and mixer lid interlocks — the 1LS1-4PG​ NEMA 4/IP67 rating withstands daily high-pressure, chemical washdown cycles required for sanitary compliance. The PG13.5 gland seals tightly with metric stainless steel washdown conduit, avoiding crevices where bacteria can grow, a common issue with ill-fitting NPT adapters.

Brownfield replacement is another steady use case: for plants running legacy Honeywell LS1/LS2 series switches or Eaton/Cutler-Hammer equivalent heavy-duty limit switches, the 1LS1-4PG​ is a near-drop-in replacement. The side rotary actuator, 1LS mounting pattern, and 10A rating match legacy specs, while the PG13.5 gland aligns with metric conduit already installed in international plants, avoiding rewiring or adapter procurement during unplanned downtime.

Related Products

1LS1-4: Identical to 1LS1-4PG​ except termination is 1/2″ NPT instead of PG13.5. the standard NA market variant for plants using imperial conduit.

1LS2-4PG: Top push roller actuator variant of the same 1LS heavy-duty series with PG13.5 gland, used for applications where top-down actuation (e.g., overhead conveyor trolley strike) is required instead of side rotary.

1LS1-A4PG: Sanitary-grade variant of the 1LS1-4PG​ with FDA-compliant white gasket and polished housing, specifically for strict hygienic food/pharma washdown applications.

LSZ1A: Adjustable extension lever accessory compatible with 1LS1-4PG, extends lever length to 3″ for applications where the actuated machine part cannot approach the switch base closely.

GLS1-4PG: Honeywell GLS series compact limit switch, lower cost, PG13.5 gland, for lighter-duty applications where 10M cycle rating of 1LS1-4PG​ is not required.

E50SA4PG: Eaton/Cutler-Hammer equivalent heavy-duty side rotary limit switch with PG13.5 gland, cross-reference replacement for 1LS1-4PG​ when Honeywell lead times are extended.

1LS3-4PG: Side rotary roller lever variant of the 1LS series with PG13.5 gland, used when the actuated part slides along the lever (vs. striking a fixed lever tip) to reduce friction and lever wear.

1LS1-4PG-R: Tested refurbished spare of the 1LS1-4PG, fully functionally validated, for legacy plants looking to stock low-cost spares for unplanned downtime.