Ask the Expert – What are the differences between the products in the Flotect® switch family?

Question: I am choosing an insertion level switch to help me monitor levels in a tank. What are the main differences between the products in the Flotect® switch family?

Answer: The Series L4, L6, L8, and L10 Flotect® switches share the same basic operating principle; as your well fills/empties, a float connected to an armature will rise/lower to activate/deactivate a switching mechanism. These mechanical devices do not require power to operate, but it is still possible to apply power across the relays in order to power a load or control an automated system.

So, which switch is best for your application? While these switches all have the same operating principle, the build, sizing, and approval ratings are very different.

Flotect® Float Switch, Series L4

The Flotect® Float Switch, Series L4, is rated as weather and explosion-proof. It is ideal for worksites requiring devices to be listed with UL and CSA for Class I, Groups C and D; Class II, Groups E, F, and G. Additionally, the L4 can carry approvals from ATEX, CE, CSA, FM, IECEx, and UL. These units offer connection sizes of 1-1/2” NPT or BSPT; a 2”, 3”, or 4” flange; or a 2” or 2-1/2” bushing, with wetted materials available in 316 SS or brass. The Series L4 switches come standard with a SPDT snap switch, but offer a DPDT snap switch as an optional circuitry upgrade.

Flotect® Liquid Level Switch, Series L6

The Flotect® Liquid Level Switch, Series L6, is rated as weather- and explosion-proof. Like the Series L4, these units would also work well in an area that requires products to be listed with UL and CSA for Class I, Groups A, B, C and D; Class II, Groups E, F, and G. The Series L6 can also carry approvals from ATEX, CE, CSA, IECEx, and UL. These units offer connections with or without an external float chamber sizes of 1”, 1-1/2”, or 2” NPT or BSPT or 1-1/2” or 2” bushing and tee. These connections are available in 303 SS or brass, and have float materials available in polypropylene or 304 SS. The Series L6 switches can be configured with SPDT or DPDT snap switch circuitry with optional gold contacts.

Flotect® Liquid Level Switch, Series L8

The Flotect® Liquid Level Switch, Series L8, comes standard in a general purpose housing, with an optional weatherproof enclosure. The L8 carries an approval for CE and is UL listed per standard 508. These units are constructed of a chemical resistant polyphenylene sulfide float and body with a 1” NPT connection size, and have pin and spring materials in 316 SS or Inconel® alloy. The Series L8 switches utilize a SPDT snap switch with optional gold contacts.

Flotect® Mini-Size Level Switch, Series L10

The Flotect® Mini-Size Level Switch, Series L10, has a NEMA 4X and IP66 rating, which is ideal for conditions requiring a weatherproof enclosure. The L10 unit also carries approvals for CE, CSA, and UL. These units offer connections with or without an external float chamber in sizes of 1”, 1-1/4” 1-1/2”, or 2” NPT, which are available in brass or 303 SS, and have float materials available in polypropylene or 304 SS. The Series L10 switches utilize a SPST hermetically sealed reed switch circuitry, which is field adjustable to be normally open or closed.

To order or learn more about the Flotect® switch product family, please visit the Dwyer website at http://www.dwyer-inst.com/