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General Purpose Flow Switch, NEMA1

Price $168.25 / each

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  • Item # 2RUL3
  • Mfr. Model # FS251
  • NSN # 5930-00-851-1923
  • UNSPSC # 39121538
  • Catalog Page # 3755
  • Shipping Weight 1.99 lbs.
Country of Origin USA Country of Origin is subject to change.
Note: Product availability is real-time updated and adjusted continuously. The product will be reserved for you when you complete your order. More

Technical Specs

  • Item General Purpose Switch
  • Min. Flow Rate (GPM) 5.8
  • Max. Flow GPM 131
  • Connection Size (In.) 1 MNPT
  • Switch Enclosure NEMA 1
  • Min. Ambient Temp. (F) 32
  • Min. Fluid Temp. (F) 32
  • Max. Fluid Temp. (F) 250
  • Max. Pressure (PSI) 160
  • Operating Velocity Range (FPM) 130 to 280
  • Switch Type Single Pole Double Throw Snap Switch
  • Contact Rating 7.4A @ 120 VAC - Full Load, 120 VA @ 120 or 240 VAC - Pilot Duty
  • Body Material Brass
  • Material of Construction Brass, SS, EPDM
  • Wetted Materials Brass, Stainless Steel, EPDM
  • Max. Operating Velocity (FPM) 600
  • Voltage 120/240
  • For Use With Water Systems
  • Application Signal Lights, Alarms, Motors, Automatic Burners and Metering Devices
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  • FS251

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Rated 4.7 out of 5 by 3reviewers.
Rated 5 out of 5 by Work great, the only manufacture we use at the hospital and our Account Manager has been anle to get us the best price we have found. April 25, 2013
  • 2015-11-27 T19:28:24.348-06:00
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Product Q&A

(1 Question : 1 Answer)

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i want the details about the connection of flow switch to a 3-phase motor starter panel for a pump.
2 years, 7 months ago
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I do not know if I can answer that, simply because the words 3 Phase Power. Using this flow switch you will have to develop a by pass or what is called a delay circuit, this delay circuit will allow a period of time to pass before it look at the position of the flow switch. This is how you use this in a motor or pump control circuit, you would hook this to the coil circuit and interrupt the coil power if the pump is not deliveing flow.

I hope this answers your question, thanks for using Grainger Ask & Answer!

2 years, 7 months ago
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  • 2015-11-27 T19:36:22.927-06:00
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