Series V4 Flotect® Vane-Operated Flow Switch

Field Adjustable – Dependable Protection Against Flow Variation or Stopping in Pipelines for Fluids, Gases and Flowing Solids

The SERIES V4 Flotect® Flow Switches is rugged and reliable, ideal for automatically protecting equipment and pipeline systems against damage from reduction or loss of flow. Time tested in thousands of pipeline installations and processing plants around the world this Series is Weatherproof, designed to meet NEMA 4 and Explosion-proof (listing included in specifications). This series can be used in pipes 1-1/2" (38.10 mm) and up.

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Product Applications

  • Protects pumps, motors and other equipment against low or no flow
  • Controls sequential operation of pumps
  • Automatically starts auxiliary pumps and engines
  • Stops liquid cooled engines, machines and processing when coolant flow is interrupted
  • Shuts down burner when air flow through heating coil fails
  • Controls dampers according to flow

Models & Ordering

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Model Description Usually Ships Price Order
V4-2-U
Ships: Next Day
Price: $302.75
Vane operated flow switch, brass body, universal vane. Next Day $302.75 Order
V4-SS-2-U
Ships: Next Day
Price: $431.75
Vane operated flow switch, 316SS body, universal vane. Next Day $431.75 Order

Can't find what you need? Build Your Custom Part. Use our Product Configurator

Specifications

Service:
Gases or liquids compatible with wetted materials.
Wetted Materials:
Vane: 316 SS; Body: Brass or 316 SS standard; Magnet Keeper: 430 SS standard, 316 SS optional; Options: Other materials also available, consult factory (e.g. PVC, Hastelloy, Nickel, Monel, Titanium).
Temperature Limit:
-4 to 275°F (-20 to 135°C) standard, MT high temperature option 400°F (205°C) [MT option not UL, CSA, ATEX or IECEx] ATEX and IECEx options, ambient temperature -4 to 163°F (-20 to 73°C); Process temperature -4 to 163°F (-20 to 73°C).
Pressure Limit:
Brass body 1000 psig (69 bar), 316 SS body 2000 psig (138 bar), optional 5000 psig (345 bar) available with 316 SS body and SPDT switch only.
Enclosure Rating:
Weatherproof and Explosion-proof. **Listed with UL and CSA for Class I, Groups C and D; Class II, Groups E, F, and G. ATEX CE 0344 EX II 2 G Ex d IIB T6 Gb -20°C≤Tamb≤73°C. -20°C≤Process Temp≤73°C. EC-Type Certificate No.: KEMA 03 ATEX 2383. ATEX Standards: EN60079-0: 2009; EN60079-1: 2007.
IECEx Certified: For Ex d IIB T6 Gb - 20°C≤Tamb≤73°C. -20°C≤Process Temp≤73°C. IECEx Certificate of Conformity: IECEx DEK 11.0071. IECEx Standards: IEC 60079-0: 2007; IEC 60079-1: 2007. Zone I. Also FM approved.
Switch Type:
SPDT snap switch standard, DPDT snap switch optional.
Electrical Rating:
UL, FM, ATEX and IECEx models 10 A @ 125/250 VAC. CSA models: 5 A @ 125/250 VAC; 5 A res., 3 A ind. @ 30 VDC . MV option: 1 A @125 VAC; 1 A res., .5 A ind. @ 30 VDC. MT option: 5 A @ 125/250 VAC. [MT and MV option not UL, CSA, FM or ATEX or IECEx].
Electrical Connections:
UL and CSA models: 16 AWG, 6" (152 mm) long. ATEX and IECEx unit: Terminal block.
Conduit Connection:
3/4" female NPT or 19.05 mm standard or M25 with -BSPT option.
Process Connection:
1-1/2" male NPT or 1-1/2" male BSPT or 38.10 mm.
Mounting Orientation:
Within 5° of vertical for proper operation. Units for horizontal installation (vertical pipe with up flow) available.
Set Point Adjustment:
For universal vane: five vane combinations.
Weight:
4 lb 8 oz (1.9 kg).
Agency Approvals:
ATEX, CE, CSA, FM, IECEx, UL**.
**No housing option (-NH) has no approvals

Features

  • Leak proof body machined from bar stock
  • Choice of custom vane calibrated for your application, Model V4, or field adjustable multilayer vane, Model V4-2-U (see set point chart)
  • Installs directly and easily into pipeline with a threadolet, tee, or flange (see application drawings)
  • Can be used in pipes 1-1/2" and up
  • Electrical assembly can be easily replaced without removing the unit from installation so that the process does not have to be shut down
  • High pressure rating of 1000 psig (69 bar) with the brass body and 2000 psig (138 bar) with the 316 SS body
  • Unique magnetically actuated switching design gives superior performance
  • Features a free-swinging vane which attracts a magnet within the solid metal switch body, actuating a snap switch by means of a simple lever arm with no bellows, springs, or seals to fail

Options

  • -D - DPDT contacts.
  • -MV - Gold Plated Contacts, options for dry circuits see electrical rating in specification, no listings or approvals).
  • -MT - High Temperature, option rated 400°F (204°C) see electrical rating in specifications, no listings or approvals.
  • -TRI - (increasing flow); -TRD - (decreasing flow), Time Delay Relay, option with 2 SPDT contacts, adjustable from 0-1 to 0-31 minutes. (no listings or approvals).
  • -316 - 316 SS Magnet Keeper, option to replace standard 430 SS.
  • -V - Vertical Up Flow, option for upward flow in vertical pipe.
  • -AT - Atex listed construction.
  • -IEC, IECEx certified construction.
  • -NH, No housing, has no approvals.

Videos

Model Chart

EXAMPLE V4 SS-2-D-U 2 1 6 EPOXY B1HC Series V4-SS-2-D-U-216-EPOXY-B1HC Flotect® Vane Operated Flow Switch, 316 SS body, DPDT, universal vane, NI 200 magnet keeper and vane block material, 316SS vane, epoxy coated housing, with 2" hex type carbon steel bushing.
SERIES V4             Flotect® Vane Operated Flow Switch
1ST SET OF OPTIONS
(Select any or all)
  SS
2
D
U
          316 SS Body (430 Magnet Keeper)
-2 Style Body
DPDT
Universal Vane
MAGNET KEEPER VANE
BLOCK MATERIAL
    1
3
        430 SST (standard)
316 SST
VANE MATERIAL       1
2
3
4
5
      316 SST (standard)
C20 SST
Hastelloy B
Hastelloy C
Monel
BODY MATERIAL         1
2
3
4
5
6
7
8
    Brass (standard)
C20
CPVC
Hastelloy B
Hastelloy C
316 SST
Monel
PVC
2ND SET OF OPTIONS           AT
EPOXY
FSV
HP
HV
IEC
MT
MV
NACE
NH
PT
ST
SLW
SW
TBC
TRD
TRI
V
W
  ATEX Approval
Epoxy Coated Housing
Full Swing Vane
High Pressure
Hinged Vane
IECEx Approval
High Temperature
Gold Contacts
Heat Treated Body
No Housing
Paper Tag
Stainless Steel Tag
Solvent Weld
Socket Weld
Terminal Block Connector
Time Delay Relay, Decreasing Flow
Time Delay Relay, Increasing Flow
Vertical Up Flow
Weld
FLANGES/BUSHINGS/
TEES/TEES & BUSHINGS
            B1FC
B1HC
B1HB
B1H4
B1HS
B2FC
B2F4
B2HC
B2HS
B2HB
B4HS
F2B1
F2C1
F2C3
F2C6
F2C9
F2H1
F2M1
F2S1
F2S3
F2S6
F2.5C1
F2.5C3
F2.5S1
F3C1
F3C3
F3C9
F3S1
F3S3
F4C1
F4C3
F4S1
T1B0
T1B2
T1S
T1P
T1CP
TB2B0
TB2B2
TB2C
TB2S
TB2P
TB2CP
TB3B0
BT3P
TB3CP
2" Flush Type Carbon Steel Bushing
2" Hex Type Carbon Steel Bushing
2" Hex Type Brass Bushing
2" Hex Type 304SS Bushing
2" Hex Type 316SS Bushing
2-1/2" Flush Type Carbon Steel Bushing
2-1/2" Flush Type 304SS Bushing
2-1/2" Hex Type Carbon Steel Bushing
2-1/2" Hex Type 316SS Bushing
2-1/2" Hex Type Brass Bushing
4" Hex Type 316SS Bushing
2" Hastelloy B 150# Flange
2" Carbon Steel 150# Flange
2" Carbon Steel 300# Flange
2" Carbon Steel 600# Flange
2" Carbon Steel 900# Flange
2" Hastelloy C 150# Flange
2" Monel 150# Flange
2" 316SS 150# Flange
2" 316SS 300# Flange
2" 316SS 600# Flange
2-1/2" Carbon Steel 150# Flange
2-1/2" Carbon Steel 300# Flange
2-1/2" 316SS 150# Flange
3" Carbon Steel 150# Flange
3" Carbon Steel 300# Flange
3" Carbon Steel 900# Flange
3" 316SS 150# Flange
3" 316SS 300# Flange
4" Carbon Steel 150# Flange
4" Carbon Steel 300# Flange
4" 316SS 150# Flange
1-1/2" Brass 125# Tee
1-1/2" Brass 250# Tee
1-1/2" 316SS 150# Tee
1-1/2" PVC Sch 80 Tee
1-1/2" CPVC Sch 80 Tee
2" Brass 125# Tee & Bushing
2" Brass 250# Tee & Bushing
2" Carbon Steel 2000# Tee & Bushing
2" 316SS Tee & Bushing
2" PVC Sch 80 Tee & Bushing
2" CPVC Sch 80 Tee & Bushing
3" Brass 125# Tee & Bushing
3" PVC Sch 80 Tee & Bushing
3" CPVC Sch 80 Tee & Bushing

Product Literature

Manuals

Catalog Pages

Product Data Sheet

Approvals

Drawings

Questions

Question
Why is the method of mounting a V4 of concern?
Answer
The vane and magnet keeper assembly near the hinge pin are very close to the mounting threads. Combined with the fact that pipe fittings are available in many variations, this produces a possibility that the customer will mount the switch in a fitting that prevents the vane from swinging. To make things worse, there is usually no way the customer can tell that this has happened. Mounting in a threaded branch connection avoids this clearance problem.
Question
How is "deadband" defined as related to the V4 switch?
Answer
Deadband is the difference between the switch actuation flow and switch deactuation flow; in general, V4 flow switches have a 45% deadband meaning deactuation occurs at approximately 55% of actuation flow.
Question
What precautions should be taken when installing a V4 switch in an extremely high flow application?
Answer
Installation with a 2 1/2" threaded branch connection is recommended to allow the vane to swing out almost parallel to the flow to reduce stress on the vane and pressure drop in the system.
Question
What does actuation and de-actuation mean?
Answer
Actuation means that the flow rate has reached a point where the microswitch trips or the contacts of the microswitch change state. De-actuation means that the flow rate has decreased to a point where the microswitch returns to its normal state.
Question
What material is used as a seal between the process fluid and the electrical portion of the switch?
Answer
The body material; as there is no separate "seal" since the body is machined from solid stock and the switch is magnetically actuated.
Question
Can a V4 switch be installed in a vertical run of pipe?
Answer
Yes, but not the standard model. Vertical pipe installations must be specified on the order and require a special spring loaded vane. Only for use in vertical up-flow applications. Please see option -V in online configurator.
Question
On your Flow Switches, which model has a Form C type contact
Answer
Form C contact is a SPDT snap switch. Many of Dwyer’s flow switches have SPDT snap switches. The V4, V6, V7, FS-2, and V8 are some of them.
Question
I have a model V4 flow switch the Micro switch failed I replaced it. I reinstalled and couldn’t accurate switch. Attempted to set as sensitive as possible I couldn’t get it to actuate, I replaced the magnet with one from another unit it works fine! Where can I order a replacement magnet?
Answer
Unfortunately, we do not sell the replacement magnet. It would be best to return the unit to the factory for repair.

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