Last fall, we introduced two new lines of float switches, the Series FS-400 Stainless Steel Vertical Float Switch and the Series FS-410 Miniature Stainless Steel Vertical Float Switch. With all stainless steel wetted materials, user-reversible logic function, and simple NPT and hex nut mounting, the FS-400 and FS-410 are versatile and reliable float switches. Now we are excited to announce that we have significantly expanded the capabilities of the switches. These new specs take the FS-400 and FS-410 from being two good float switches to being two of the best float switches.
New Wattage: 100W
First, we increased the wattage on both the FS-400 and FS-410 to 100 W, and not just in certain circumstances. Whether you use the switch as a logic point in a controller, or wire it in-line with an alarm indicator, it can handle a total resistive load of 100 W across all temperature ranges. That’s a pretty significant upgrade from 30 W and 60 W, which are much closer to industry standard.
CSA Explosion Proof
Next, we added hazardous location certifications for our standard temperature range switches. Specifically, both the FS-400-S and FS-410-S are CSA Class I, Class II, and Class III explosion proof. That means you can safely use an FS-400-S or FS-410-S in an area with anything from acetylene to propane, metal, coal, or grain dusts, or even combustible fibers. Basically, if you need a liquid level switch in an environment with nasty stuff in the air, APG’s stainless steel vertical float switches are what you are looking for.
NSF 169 Certification
Finally, we added NSF 169 certification on all FS-400 and FS-410 float switches. All of them, every single one. Whether you need standard or high temperature range, standard or miniature size, all of our stainless steel vertical float switches are certified for use in specialty purpose food equipment. It really doesn’t get any easier than that.
Many Uses, One Float Switch
We hope you share our excitement about the improvements we’ve made to the FS-400 and FS-410 vertical float switches. When you can use one type of switch in multiple applications, you don’t need to keep track of as many switches. With a higher-than-industry-standard wattage, Class I, II, and III approvals on standard temperature ranges, and across the board NSF 169 certification, the FS-400 Stainless Steel Vertical Float Switch and FS-410 Miniature Stainless Steel Vertical Float Switch are your all-purpose, all-situation vertical float switches.
Not sure which float switch is the best float switch for your level monitoring needs? Send our Measurement Experts an email or give them a call. We’d love to help you identify the key ingredients for successful float switch use.
WRITTEN BY

Sami T.
Sami Thompson is APG’s Marketing Technical Writer and has been with the company since 2022. With a master’s degree in English from Utah State University and a 40-page thesis publication under her belt, Sami has a demonstrated strong writing background. In her free time, Sami enjoys reading and birdwatching.