SANKYO Seisakusho S-K16AHS-85 Float Switch

SANKYO Seisakusho S-K16AHS-85 Heavy-Duty Marine Level Float Switch

The SANKYO Seisakusho S-K16AHS-85 is a flange-mounted mechanical/magnetic point level float switch engineered specifically for marine engine room service and harsh plant environments. Built in Japan by Sankyo Seisakusho Co., Ltd., this instrument monitors critical liquid levels across marine auxiliary boilers, cascade tanks, fuel oil settling tanks, ballast tanks, and engine room bilge wells.

The unit utilizes a counterbalanced, float-actuated mechanism coupled through an isolated barrier to an internal heavy-duty microswitch assembly. This design isolates electrical switchgear from high-temperature oils, condensates, and pressurized liquid media. With high switching capacity (up to 15A AC across 125V/250V/480V lines), the S-K16AHS-85 can directly energize motor starter coils, sounders, and solenoid trip circuits without interposing relays.

Model Details

• Primary Model: S-K16AHS-85
• Series Base: S-K16 / S-K16AH Series
• Drawing / Standard Specification: TB-11760-E / TB-30734-E related series
• Related Sankyo Models:
  • S-K16AHS-110 (110 mm stroke / lever variant)
  • S-K16-AH / S-K16AH (Standard horizontal/top mount)
  • S-K16ES / S-K16ES-N (External chamber/flanged level switch)
  • S-K160P (Specialized flow/level assembly)
• Functional Direct Alternatives: Mobrey S01DB-F104/1, Besta U5A-01-140, KSR Kuebler ALV series

Technical Details

Compatibility

• Auxiliary Marine Boilers & Steam Generators: Aalborg / Alfa Laval Mission OL/OS, Miura Marine Steam Boilers, KangRim auxiliary composite boilers (cascade tank and atmospheric hotwell level regulation).
• Purifier & Fuel Conditioning Modules: Alfa Laval (S/P-Flex), Westfalia (OSD/OSC series), Mitsubishi Kakoki Kaisha (SJ series) sludge and buffer tank alarms.
• Oily Bilge Water Separators: RWO Skit/S-VE, Decapower, Taiko Kikai, and Victor Marine bilge water alarm automation.
• Marine Alarm Monitoring Systems (AMS): Direct dry-contact interface to Kongsberg K-Chief / AutoChief, Nabtesco, JRCS, Hyundai ACONIS, and Praxis automation systems.

Applications

• Engine Room Bilge Wells: Reliable high-level alarm signaling to prevent flooding and trigger bilge stripping pump automation.
• Heavy Fuel Oil (HFO) & MDO Day/Settling Tanks: High-high (HH) overflow alarm and auto-fill pump cut-in/cut-out level management.
• Boiler Cascade / Feed Water Hotwells: Continuous maintenance of pump suction head preventing boiler feedwater cavitation.
• Lube Oil Storage & Sump Tanks: Low-level trip interlocks to safeguard main engine and auxiliary engine lubrication systems.
• Expansion Tanks for Cooling Water: High-expansion and low-makeup signaling in central high-temperature (HT) / low-temperature (LT) cooling circuits.

Frequently Asked Questions

Can the S-K16AHS-85 float switch handle heavy fuel oil (HFO) applications?

Yes. The wetted elements are fabricated from industrial SUS304/SUS316 stainless steel, making it resistant to crude hydrocarbons, heavy fuels, and elevated media temperatures up to 100°C (with peak excursions up to 120°C).

What is the primary difference between S-K16AHS and S-K16ES models?

The S-K16AHS is an internal arm-and-float type designed for direct tank wall or top mounting, whereas the S-K16ES features a dedicated external float chamber with flanged bypass connections (typically JIS 5K-65A) intended for boiler steam drums and cascade tanks.

Is an external interposing relay required to drive an alarm horn or contactor?

In most scenarios, no. The internal microswitch provides a 15A rating at 125V/250V/480V AC, allowing direct switching of starter coils, valves, and warning beacons without burning contacts.

How do you verify the float switch during engine room PMS surveys without opening the tank?

Models equipped with a manual test lever allow checking without altering the fluid level. If your variant has an external manual test shaft, rotate the lever to mechanically lift the float arm and trip the microswitch contacts while verifying the alarm on the AMS console.

How is the switch protected against vessel roll and pitch?

The internal microswitch mechanism incorporates calculated hysteresis and high-spring-rate detents, preventing rapid on-off cycling caused by sloshing or hull motions in heavy seas.