Dwyer PFT User Manual

Series PFT Paddlewheel Flow Sensor

∞∞

30 30

BUBBLES (AVOID)

SEDIMENTS (AVOID)

OK OK

30 30

1/2˝ NPT

2-1/2

[

63.50]

-13/16

[

96.84]

-1/2˝ NPT

-25/64

[

60.72]

7-29/32

[200.94]

2˝ HEX [50.80]

Specifications - Installation and Operating Instructions

Bulletin F-PFT

he Series PFT is a paddlewheel flow sensor used to monitor liquid flow rates in

pipes from 1-1/2 to 40˝ with one size adjustable sensor. A square wave output signal is generated with frequency proportional to flow velocity.

OPERATING PRINCIPLE

The PFT uses inductive sensing to sense the blades of the impeller as they rotate. Sensor technology does not use magnets allowing low flow rate monitoring and no concerns with magnetic material in the flow.

INSTALLATION

Ensure that the process fluid is compatible with the wetted materials, and do not exceed the maximum device ratings.

Ensure that the system is not pressurized before installing or removing this device or other objects from the system. The device and/or object may become a projectile.

Fitting Position

Bubbles, turbulence, and sediments will cause improper operation. For best operation, mount 30° to 150° off vertical on horizontal runs (See Figure 1). Allow a straight run of at least 10 pipe diameters upstream and 5 pipe diameters downstream to insure optimal flow measurement. See Table 1 for recommendations for other mounting requirements.

Upstream Item

Flange Reducer Valve/Pump 90° Elbow

Upstream Diameters Needed

10 15 50 20

Table 1: Fitting Location

SPECIFICATIONS Service: Water-based fluids.

ange: 1.2 to 25 ft/s (0.37 to 7.62 m/s).

etted Materials: Body and fitting: brass or 316 SS; fitting o-ring: FKM standard,

silicone or Buna-N optional; impeller: 316 SS; shaft: tungsten carbide standard or 316 SS optional; bearing: PTFE standard, carbon graphite optional.

Linearity: ±1.0% of full range. Repeatability: ±0.5% of full range. Temperature Limits: -40 to 212°F (-40 to 100°C). Pressure Limits: 400 psig (27.6 bar) @ 100°F (37.8°C), 325 psig (22.4 bar) @

212°F (100°C).

Process Connection: 1-1/2˝ NPT male standard, 2˝ NPT male optional. Output:

Pulse: NPN open collector with square wave output, rated 60 V @ 50 mA

maximum. Frequency: 3.2 to 200 Hz. Pulse Width: 2.5 msec ±25%.

4 to 20 mA: 4 mA is 0 ft/s, 20 mA is 25 ft/s. Power Requirement: 10 to 35 VDC. Power Consumption: 40 mA (max.). Electrical Connection: 22 AWG shielded UL type PTLC rated 105°C, 20´ (6.1 m)

long with cable gland. Can be extended up to 2000´ (609 m) with similar cable. Optional UL listed burial rated cable.

Enclosure Rating: NEMA 6P (IP67). Housing Materials: Brass or 316 SS. Weight: 3 lb. Agency Approvals: CE.

Figure 1: Mounting Orientation

W.E. ANDERSON DIV., DWYER INSTRUMENTS, INC.

P.O. BOX 358 • MICHIGAN CITY, INDIANA 46361 U. S. A.

Phone: 219/879-8000 www.dwyer-inst.com Fax: 219/872-9057 e-mail: info@dwyer-inst.com

onnecting Sensor to Fitting

DIRECTION OF FLOW

PIPE

ALIGNMENT ROD

BOTTOM OF

SENSOR FLANGE

PWR SUPPLY 24 VDC

TYPICAL PLC HIGH SPEED COUNTER INPUT

RED

+PWR

OUT

COM

WHITE

LACK

WR SUPPLY

RED W

HITE

BLACK

ULL UP

RESISTOR

PFT

+PWR

OUT

COUNTER WITH L

OGIC LEVEL INPUT

-COM

WR SUPPLY

RED

WHITE - NO CONNECTION

4-20 mA LOOP

BLACK

RECEIVER

t is recommended to use a weld-on or saddle female fitting with 1-1/2˝ or 2˝ NPT

onnection depending on sensor model. Use proper pipe sealant on sensor

hreads. When threading the sensor into the fitting use the wrench flats on the

t bottom of the housing to prevent damage to the sensor.

The sensor must be aligned with the direction of flow. On the side of the sensor

ody is a hole for the included alignment rod. Insert the supplied alignment rod into

he alignment hole (Do not turn the alignment rod to loosen the screw in the

lignment hole). When threading the sensor into the fitting make sure that when the

od is inserted into the hole it is pointing downstream in the direction of flow. Try

r to line it up as best as can be done. If the sensor is off slightly once threaded into the fitting then the sensor can be rotated in the housing during final installation but adjustment is only ±60°.

ensor Height

he sensor must be installed so that the impeller shaft is located 10% inside the

T pipe ID. To install properly the sensor install height, “H” shown in Figure 2, must be figured and used. Table 2 in this instruction manual has “H” dimensions for standard pipe materials and sizes.

f your application pipe is not listed in Table 2 it will need to be calculated with the

ollowing procedure:

. Using a ruler measure the pipe ID and the pipe wall thickness.

Pipe Wall Thickness:_______ Pipe ID:_______

2. Use the following equation to figure “H”: H = 5.85 – Pipe Wall Thickness – (0.10 x Pipe ID) H = _____

nce “H” is known from the chart or from the equation adjust the sensor so that “H”

s the distance from the bottom of the flange to the top of the pipe. The insertion

i height of the sensor is adjustable by loosening the top and bottom nuts holding the flange and then moving the sensor by the flange up or down as needed.

LECTRICAL CONNECTION

ulse Output Wiring

he PFT has a NPN open collector output. The output rating is 60V @ 50 mA

aximum. Typical wiring to a PLC or counter is shown in Figure 3 and Figure 4.

m When wiring to a counter, select the Power Supply voltage and Dropping Resistor according to the counter’s instructions and make sure the Power Supply is within the 10-35 VDC specification of the PFT.

o insure noise immunity, wire the shield conductor to an earth ground.

igure 3

igure 4

The PFT can also be wired in a two-wire pulse output, 600 µA / 40 mA configuration

ith the red and black leads only to replace competitor units. Unit needs 600 µA of

ower and produces 40 mA 2.5 ms pulses. Consult factory for details.

4-20 mA Output Wiring

Final Sensor Alignment

The sensor must be aligned with the direction of flow. Insert the supplied alignment rod into the hole in the side of the sensor. The hole should be roughly in line based on installing the sensor into the fitting earlier. To make final adjustments loosen the three 3/32˝ set screws around the flange, the supplied alignment rod can be used with these screws. With the alignment rod in the alignment hole the sensor can now be rotated ±60° (Do not turn the alignment rod to loosen the screw in the alignment hole). Once final alignment is made tighten the screws in the flange and tighten the height adjustment nuts.

Figure 2: Sensor Install Height

CALIBRATION TABLES

The PFT uses K factors for calibration. See Table 2 in this instruction manual for K factors based on pipe type and size used in the application.

For 4-20 mA output version use the following equation to convert to flow rate.

q = (I-4) x K

Nomenclature: q = Liquid volumetric flow rate I = Transmitted mA output K = K - factor. If use GPM/mA then q will be in U.S. GPM. If use LPM/mA then q will be in LPM.

Figure 5

AGENCY APPROVALS AND TEST STANDARDS

CE: CENELEC EN 55011: 2006

CENELEC EN 61326-1: 2006 IEC 61000-4-2: 2008 IEC 61000-4-3: 2006 IEC 61000-4-4: 2004 IEC 61000-4-5: 2005 IEC 61000-4-6: 2006 CENELEC EN 55022: 2006 2004/108/EC EMC DIRECTIVE

Note: For 4-20 mA output models only under the 10 V/M RF field as specified in IEC 61000-4.3, linearity may be as high as ±3.7%. Under normal ambient conditions linearity is ±1%.

MAINTENANCE & REPAIR

Inspect and clean wetted parts at regular intervals. Disassembly or modifications made by the user will void the warranty and could impair the continued safety of the product. If repair is required obtain a Return Goods Authorization (RGA) number and send the unit, freight prepaid, to the address below. Please include a detailed description of the problem and conditions under which the problem was encountered.

Dwyer Instruments, Inc. Attn: Repair Department 102 Indiana Hwy 212 Michigan City, IN 46360

PARTS

P-PFT-KITA: Contains impeller, PTFE bearings, cage bearing set screws, tungsten carbide shaft

P-PFT-KITB: Contains impeller, PTFE bearings, cage bearing set screws, 316SS shaft

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