Hanla FMS-1H-WS Horizontal Float Level Switch

Hanla FMS-1H-WS Horizontal Type Float Level Switch

The Hanla FMS-1H-WS is a side-mounted, magnetic horizontal float level switch engineered for high-reliability liquid point-level alarm and pump automation across marine and harsh industrial environments. Operating on a hermetically isolated, repulsion/attraction magnetic mechanism, the process-wetted components remain completely segregated from the electrical microswitch housing via a non-magnetic solid diaphragm wall.

This separation prevents process fluid leakage, pressure bypass, or vapor migration into the electrical termination chamber. Built with a rugged, marine-grade aluminum bronze (ALBC 2) or cast aluminum alloy housing and an argon-gas-welded SUS304/SUS316 stainless steel float, the FMS-1H-WS stands up to turbulent tank slurries, viscous heavy fuel oils (HFO), diesel oil (MDO/MGO), fresh water, and bilge/sludge environments.

Model Details:

• Model Series: FMS (Hanla Horizontal Mounted Float Level Switch)
• Connection Type (1): A-Flange (Square Flange Mounting)
• Application Characteristic (H): General Purpose Liquid Point Level Sensing
• Enclosure Rating (W): Weatherproof Type (IP56 enclosure protection)
• Contact Arrangement (S): SPDT (Single Pole Double Throw, 1 Form C)
• Manufacturer Part Number (MPN): FMS-1H-WS (Internal Cross Reference / Ordering Code: HAN10101 / FMS-1H-WS-T without test lever)

Key Features

1. Magnetic Barrier Isolation: 100% separation between the process liquid and electrical switch compartment via a solid non-magnetic partition wall, completely eliminating shaft packing leaks.
2. Heavy-Duty Contact Capacity: Integrated 250VAC/5A microswitch directly triggers motor starters, solenoid pilot valves, and shipboard alarm annunciators without requiring interposing relays.
3. High-Thermal and High-Pressure Tolerance: Continuous operation up to 180°C at 10 bar allows safe deployment in boiler feed, thermal oil, and steam-heated fuel settling tanks.
4. Argon-Welded Float Assembly: Heavy-gauge SUS304/SUS316 float withstands extreme sloshing, mechanical fluid shock, and dense sludge buildup without water ingress.
5. Low-Density Media Capability: Calibrated buoyancy operates reliably in light hydrocarbons down to 0.65 Specific Gravity.

Applications

• Marine Machinery Spaces: Heavy Fuel Oil (HFO), Marine Diesel Oil (MDO/MGO), and Lube Oil (M/E & A/E LO) service, settling, and storage tanks.
• Bilge & Sludge Management: Engine room bilge holding wells, sludge collection tanks, and separator overflow chambers.
• Auxiliary Utility Systems: Fresh water generator storage tanks, boiler cascade/feedwater tanks, and expansion tanks.
• Sewage & Greywater Units: Vacuum collection holding tanks and greywater lift tanks.
• Industrial Liquid Systems: Bulk chemical containment, hydraulic power unit (HPU) reservoirs, and industrial cooling towers.

Part Number Cross-References

• Hanla Level / Hanla IMS: FMS-1H-WS, FMS1HWS, HAN10101, FMS-1H-WS-T (Functional Alternate with Test Device)
• Nihon Kagaku (NK): HLS-100 Series side-mount float switch
• Musasino: Level switch models HM-10, FS-10 series
• KDG / Mobrey: Series 003 / M-Switch Side Mounting Magnetic Level Switch (flange adapter may apply)
• Sewon / Samgong: S-FMS Series horizontal level contacts

Frequently Asked Questions

What is the difference between Hanla FMS-1H-WS and FMS-1H-WS-T?

The suffix -T denotes an external manual mechanical test device (test lever). The FMS-1H-WS is the standard unit without an external test lever. Both share identical mounting flanges, microswitch ratings (250V 5A), pressure limits (10 bar), and stainless steel internal mechanisms.

Can the Hanla FMS-1H-WS be used in explosion-proof (Ex d) zones?

The standard FMS-1H-WS has an IP56 weatherproof enclosure. For hazardous rated locations requiring direct flameproof certification, select the Hanla FMS-1H-ES or FMS-2H-ES series (Ex d IIC T6). However, the FMS-1H-WS can be used in hazardous gas locations if connected as simple apparatus through a certified Ex-i intrinsically safe barrier.

Can I install this switch for heavy fuel oil (HFO) tanks?

Yes. The FMS-1H-WS is designed for HFO service up to 180°C and 10 bar working pressure. Its minimum specific gravity threshold is 0.65, making it well suited for hot marine residual fuels.

What are the microswitch terminal connections inside the housing?

The unit contains an SPDT microswitch terminal block marked C (Common), A (Normally Open), and B (Normally Closed). The connection makes C–A when the level rises, and makes C–B when the level falls. An additional terminal screw is provided for casing ground.