Mcdonnell & Miller FS8-WG-SL Switch

The McDonnell & Miller FS8-WG-SL is a heavy-duty liquid flow switch designed for demanding hydronic and process cooling systems where reliability is non-negotiable. This specific model features gold-plated contacts and sealed leads, making it the preferred choice for low-voltage signaling and environments prone to moisture or dust. Built with a NEMA 4X enclosure, it provides superior protection against corrosion and external contaminants. The unit utilizes a sealed Monel bellows and a magnetic switching mechanism to ensure a leak-proof seal and precise responsiveness. With its 1" NPT connection and SPDT snap switch, this flow switch effortlessly integrates into existing boiler or chiller control loops. The sensitivity adjusting screw allows for field calibration, ensuring the system triggers accurately at the required flow rates.

• Enhanced Connectivity: Features gold-plated contacts for high-integrity switching in low-energy or PLC circuits.
• Environmental Protection: The sealed leads and NEMA 4X rating provide a water-tight and dust-tight seal for outdoor or wash-down areas.
• Vessel Integrity: Equipped with a sealed Monel bellows to prevent process fluid from entering the switch housing.
• Field Versatility: Includes four stainless steel paddles (1", 2", 3", and 6") for broad pipe size compatibility and a sensitivity adjusting screw for fine-tuning.
• Robust Performance: Rated for a maximum pressure of 160 psi and fluid temperatures up to 225°F.

Common Questions Regarding the FS8-WG-SL

Can this flow switch be used with low-voltage controllers?
Yes. The gold-plated contacts are specifically designed to handle low-current signals (milliamps) typically found in modern building automation systems without the contact oxidation common in standard switches.

What is the purpose of the sealed leads?
The sealed leads provide an extra layer of protection against moisture migration through the conduit, ensuring the internal electrical components remain dry in high-humidity or outdoor applications.

How do I adjust the sensitivity for low-flow applications?
Adjustments are made using the sensitivity adjusting screw located under the cover. Turning the screw clockwise increases the flow rate required to actuate the SPDT snap switch.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.