+GF+ 2540 User guide

10x I.D. 5x I.D.

Inlet

Outlet

Flange

15x I.D. 5x I.D.

Reducer

20x I.D. 5x I.D.

90° Elbow

50x I.D. 5x I.D.

40x I.D. 5x I.D.

25x I.D. 5x I.D.

2 x90° Elbow

2 x 90° Elbow
3 dimensions

Valve/Pump

Signet 2540 High Performance Flow Sensor

*3-2540.090*

3-2540.090 Rev. 10 01/19

Location of Fitting

Pipe fi ttings MUST be installed by a certifi ed
welder only. GF Signet will not assume liability
of any kind for improper fi tting installations.

Recommended sensor upstream/downstream mounting requirements.

English

Operating Instructions

• English

• Deutsch

• Français

• Español

• Português

• Italiano

• 中文

Sensor Mounting Position

Vertical mounting is recommended for best
overall performance. Mount at a maximum of
30° when air bubbles are present.
DO NOT mount on the bottom of the pipe
when sediments are present.

-

30°

0°

Process Pipe

Table of Contents

Warranty Statement .............................................................................. 2

Product Registration ............................................................................. 2

Safety Information................................................................................. 2

Dimensions ........................................................................................... 2

Specifi cations........................................................................................ 3

Sensor Wiring ....................................................................................... 3

Electronics Module Installation and removal ........................................ 4

Installation............................................................................................. 5

Calculating the H Dimension ................................................................ 6

Standard and Hot-Tap Sensor Installation ............................................ 7

Standard Sensor Removal.................................................................... 8

Hot-Tap Sensor Removal...................................................................... 9

Maintenance ......................................................................................... 9

K-Factors ............................................................................................ 10

Ordering Information ........................................................................... 12

+30°

Warranty Information

Paddlewheel Maintenance

Refer to your local Georg Fischer Sales offi ce for the most
current warranty statement.

All warranty and non-warranty repairs being returned must
include a fully completed Service Form and goods must be
returned to your local GF Sales offi ce or distributor.
Product returned without a Service Form may not be
warranty replaced or repaired.

Signet products with limited shelf-life (e.g. pH, ORP, chlorine
electrodes, calibration solutions; e.g. pH buff ers, turbidity
standards or other solutions) are warranted out of box but not
warranted against any damage, due to process or application
failures (e.g. high temperature,
mishandling (e.g. broken glass,

chemical poisoning, dry-out) or

damaged membrane, freezing

and/or extreme temperatures).

Product Registration

Thank you for purchasing the Signet line of Georg Fischer
measurement products.

If you would like to register your product(s), you can now
register online in one of the following ways:

• Visit our website www.gfsignet.com.
Under Service and Support click on

Product Registration Form

• If this is a pdf manual (digital copy),

click here

Paddlewheel fl ow sensors are subject to wear and may require
maintenance and replacement of mechanical parts (rotors,
pin, O-rings, bearings, retainers, etc.). The frequency of
recommended maintenance will vary based upon application
specifi cations, characteristics of the measured fl uid, and
installation details. These can include, but are not limited
to: process fl owrate, occurrence of water hammer, fl uid
corrosiveness and abrasiveness, sensor installation relevant to
other equipment.

GF Signet off ers individual replacement parts and rotor
replacement kits, which include replacement instructions,
allowing customers to perform fi eld maintenance and reduce
application down-time. Please refer to the Paddlewheel
Replacement section (page 9) or contact your local GF Sales
Representative with any questions.

Dimensions

Standard Sensor Dimensions:
2540-1(S) = 1½ in. NPT fi tting
2540-2(S) = IS0 7-R 1½ fi tting

7.5 m (25 ft.)
integral cable

64 mm (2.5 in.) dia.

Safety Information

1. Do not remove from pressurized lines.

2. Do not exceed maximum temperature/pressure

specifi cations.

3. Wear safety goggles or faceshield during installation/

service.

4. Do not alter product construction.

5. Apply sealant or PTFE tape to sensor threads,

inspecting threads to ensure integrity.

Do not install a sensor with damaged threads.

Caution / Warning / Danger

Indicates a potential hazard. Failure to follow all warnings
may lead to equipment damage, injury, or death

Personal Protective Equipment (PPE)

Always utilize the most appropriate PPE during
installation and service of Signet products.

Pressurized System Warning

Sensor may be under pressure, take caution to vent
system prior to installation or removal. Failure to do so
may result in equipment damage and/or serious injury.

O-ring
seal (1)

Hot-Tap Sensor Dimensions:
2540-3(S) = 1½ in. NPT fi tting

2540-4(S) = IS0 7-R 1½ fi tting

7.6 m
(25 ft.)
cable

Adjustable

length

64 mm (2.5 in.) dia.

127 mm

(5.0 in.)

Sensor fitting:
1½ in. NPT or
ISO 7-R 1½ thread

24 mm (0.94 in.) dia.

457 mm

(18 in.)

Note / Technical Notes

Highlights additional information or detailed procedure.

O-ring
seals (2)

Adjustable

length

2

Signet 2540 High Performance Flow Sensor

Bleed
valve

Sensor fitting:
1½ in. NPT or
ISO 7-R 1½ thread

24 mm (0.94 in.) dia.

Specifi cations

General Data

Flow velocity range ............... 0.1 to 6 m/s (0.3 to 20 ft/s)

Linearity ................................ ±1% of full range

Repeatability ......................... ±0.5% of full range

Pipe range:

Standard version .................. 38 to 610 mm (1.5 to 24 in.)

Hot-Tap version .................... 38 to 914 mm (1.5 to 36 in.)

Sensor fi tting options ............ 316 SS with 1.5 in.

NPT threads,OR 316 SS with
IS0 7-R 1½ threads

Cable length ......................... 7.6 m (25 ft), can splice up to

300 m (1000 ft)

Cable type ............................ 2-conductor twisted-pair with

22 AWG shield

Electrical Data

Supply voltage ...................... 5 to 24 VDC

Supply current ...................... 1.5 mA max.

Output type ........................... Open collector, sinking

Output current....................... 10.0 mA max.

Wetted Materials

Sensor body ......................... 316 stainless steel

Sensor fi tting......................... 316 stainless steel

Sensor fi tting O-rings ............ Standard FKM, optional EPDM

Rotor ..................................... 17-4PH-1 Stainless Steel

Rotor shaft ............................ Tungsten carbide (standard)

316 stainless steel (option)

Shaft retainers (2) ................. 316 stainless steel

Rotor bearings (2)................. Carbon fi ber reinforced PTFE

Quality Standards

Manufactured under ISO 9001 for Quality, ISO 14001

for Environmental Management and OHSAS 18001 for

Occupational Health and Safety.
China RoHS (Go to www.gfsignet.com for details)
This device complies with Part 15 of the FCC rules

Operation is subject to the following two conditions:

1) This device may not cause harmful interference, and,

2) This device must accept any interference
received, including interference that may
cause undesired operation.

Fluid Conditions
Maximum operating pressure/temperature:
Sensor with standard FKM

sensor fi tting O-rings ......... 17 bar (250 psi) @ 82 °C (180 °F)

Sensor with optional EPDM

sensor fi tting O-rings ......... 17 bar (250 psi) @ 100 °C (212 °F)

Note:

Pressure/temperature specifi cations refer to sensor
performance in water. Certain chemical limitations may apply.
Chemical compatibility should be verifi ed.

2540 Hot-Tap sensor specifi cations and limitations
depend on the lowest maximum rating of the
components associated with the system. For
example, if a ball valve in the system is rated at
a maximum 100 psi @ 175 °F, you must limit the
entire system's maximum pressure/temperature
rating to 100 psi @ 175 °F. All higher maximum
specifi cations MUST yield to the component with
the lowest maximum specifi cation.

Maximum Operating Pressure/Temperature:

• 17 bar (250 psi) @ 82 °C (180 °F) with
standard FKM sensor fi tting O-rings.

• 17 bar (250 psi) @ 100 °C ( 212 °F)
with optional EPDM sensor fi tting O-rings.

Sensor Wiring

Signet Instruments

½ in. NPT conduit port

Black (5 to 24 VDC)

Red (signal out)

Silver (DC return)

• Use 2-conductor shielded cable for cable extensions up to
300 m (1000 ft)

• Maintain cable shield through splice.

Other Brands

black

silver

red

• Pull-up resistor required (10 kΩ recommended).

• Use 2-conductor shielded cable for cable extensions up to
300 m (1000 ft)

• Maintain cable shield through splice.

10 kΩ

+

-

Gnd.

Input

Blk, sensor
power

Red, freq.
input

Shld,
Gnd

instrument

5 to 24
VDC

Other
instrument

manufactured date code = mm/yy
ex. 04/08
04 - month of April

08 - year 2008

04/08

Signet 2540 High Performance Flow Sensor

3

Electronics Module Installation and Removal

The electronics module of this sensor can be replaced without removing the steel sensor body from the line.

1. Loosen liquid tight connector cap.

2. Loosen liquid tight connector compression fi tting from sensor body.

3. Grasp the electronics at the rubber strain relief (do not pull on cable) and pull fi rmly.

To reinstall the electronics module:

• Insert module into sensor housing, making sure module is fully seated.
The tip of the electronic module must bottom-out in the sensor housing.

• Replace the liquid tight connector assembly.
Note: Apply thread sealant to the liquid tight connector threads.

To install the cable inside protective conduit, remove the liquid tight connector completely.
Thread ½ in. conduit into top of sensor body.

Liquid Tight Connector-Cap

½ in. NPT Threads

Liquid Tight Connector­Compression Fitting
w/ ½ in. NPT threads

Electronics Module
3-2541.260-1 (for Standard sensor)
3-2541.260-2 (for Hot-tap sensor)

NOTE: Apply thread sealant to the
liquid tight connector threads.

Grip the electronics
module at rubber strain
relief

4

Signet 2540 High Performance Flow Sensor

Installation

The following items are required to properly install
Signet 2540 Sensors.

Hardware, Standard Sensor

• Female pipe fi tting (weld-on or saddle) with 1½ in. NPT
or ISO 7-Rc 1½ threads

• 32 mm (1¼ in.) diameter drill

• Pipe thread sealant

• Tape measure

Hardware, Hot-Tap Sensor

The Hot-Tap sensor requires all the standard sensor items
plus:

• Hot-Tap drilling machine (e.g., Mueller drilling machine
or equivalent)

• Female ball or gate valve (full port only) with 1½ in.
NPT or ISO 7-Rc 1½ threads

• Male pipe nipple, 32 mm x 50 mm (1½ in. x 2 in.)
with 1½ in. NPT or ISO 7-R 1½ threads

• Hot-Tap installation tool (purchased separately)

Standard Fitting Installation

A. Depressurize and drain pipe.

B. Wearing safety face protection, drill a

32 mm (1¼ in.) diameter hole in the pipe.

C. Install the pipe fi tting of the outside of the pipe

according to the manufacturer's instructions. Failure
to follow these instructions may result in serious bodily
injury and/or product failure.

Hot-Tap Fitting Installation

A. Install the pipe fi tting on the outside diameter of the

pipe according to the manufacturer's instructions.
Failure to follow these instructions may result in
serious bodily injury and/or product failure.

B. Install the pipe nipple and isolation valve (ball or gate

valve) onto the external pipe fi tting using pipe sealant
on the threads. (Fig. 2)

C. Wearing safety face protection, install

an appropriate hole cutting tool per
manufacturer's instructions (e.g., Mueller
drilling machine) with a 32 mm (1.25 in.)
drill onto the top of the isolation valve,
ensuring a tight fi t. Use the recommended drill bit

size or damage to the isolation valve may occur.

D. Open the isolation valve and insert the drill through

the valve and cut the sensor clearance hole. After the
hole is cut, withdraw the drill from the isolation valve
and close the valve. Remove the drilling machine per
manufacturer's instructions. (Fig. 3)

E. Install the sensor fi tting/bleed valve into the top of the

isolation valve. Make sure the bleed valve clears the
handle of the isolation valve during operation.

D. Remove sensor fi tting from sensor assembly.

E. Thread sensor fi tting into pipe fi tting. (Fig. 1)

sensor
fitting

process

pipe

pipe

fitting

pipe sealant recommended

Fig. 1

customer supplied
ball or gate valve

customer supplied
nipple: 40 x 50 mm
(1.50 x 2 in.) long

process pipe (side view)

Fig. 2

make sure
bleed valve
clears isolation
valve handle

sensor fitting

bleed valve

process pipe

Fig. 3

Signet 2540 High Performance Flow Sensor

5

A

B

1

2

3

4

5

6

1

2

3

4

5

A

B

1

2

3

4

5

6

1

2

3

4

5

pipe I.D.

wall

A

B

1

2

3

4

5

6

1

2

3

4

5

incorrect

correct

Calculating the H Dimension

Before installing the sensor some critical dimensions must be established (for Hot-Tap installations,
we assume the pipe dimensions are known). The rotor shaft must be located 10% inside the pipe
I.D. to ensure accurate calibration capability. To accomplish this, the "H" dimension is measured
from the outside surface of the pipe to the bottom of the sensor fl ange.

Nominal "H" dimensions for standard pipes are listed here. For non-standard pipe dimensions,
calculate the "H" dimension using the formula listed below. The wall thickness and inside diameter
(I.D.) are required for the "H" dimension calculation.

The 6 inch ruler (included) may be used to measure your pipe I.D. and wall thickness up to 5 inches
(standard sensors only).

Pipe wall thickness: ___________ Pipe I.D.: ___________

Standard Sensors:

H = 5.23 - wall thickness - (0.10 x I.D.)

Hot-Tap Sensors:

H=15.39 in. - wall thickness - (0.10 x I.D.)

Example: 3.0 inch schedule 80 wrought steel
Wall thickness = 0.3 in. / Inside diameter = 2.9 in.

H = 5.23 - 0.3 - (0.10 X 2.9) / H = 117.86 mm
(4.64 in.)

Record your sensor's "H" dimension for future
reference:

After correct dimensions are calculated and
recorded, the sensor can be installed in the fi tting.
The Standard and Hot-Tap versions require
substantially diff erent procedures.

sensor flange

H Dimensions, Standard Sensors (2540-1, 2540-2)

Wrought Steel Pipe Per ANSI 36.10

NPS
inches

SCH 40
inches

SCH 80
inches

STD
inchesXSinches

1½ 4.924 4.880 4.924 4.880

2 4.869 4.818 4.869 4.818

2½ 4.780 4.722 4.780 4.722

3 4.707 4.640 4.707 4.640

3½ 4.649 4.576 4.649 4.576

4 4.590 4.510 4.590 4.510

5 4.467 4.374 4.467 4.374

6 4.344 4.222 4.344 4.222

8 4.110 3.968 4.110 3.968

10 3.863 3.680 3.863 3.755

12 3.630 3.405 3.655 3.555

14 3.480 3.230 3.530 3.430

16 3.230 2.955 3.330 3.230

18 2.980 2.680 3.130 3.030

20 2.755 2.405 2.930 2.830

22 ----- 2.130 2.730 2.630

24 2.280 1.855 2.530 2.430

Stainless Steel Pipe Per ANSI B36.19

NPS

SCH 5S

inches

inches

1½ 4.988 4.953 4.924 4.880

2 4.940 4.905 4.869 4.818

2½ 4.876 4.847 4.780 4.722

3 4.814 4.784 4.707 4.640

3½ 4.764 4.734 4.649 4.576

4 4.714 4.684 4.590 4.510

5 4.586 4.567 4.467 4.374

6 4.480 4.460 4.34 4 4.222

84.2804.2494.1103.968

10 4.048 4.023 3.863 3.755

12 3.830 3.811 3.655 3.555

14 3.705 3.680 ----- -----

16 3.498 3.480 ----- -----

18 3.298 3.280 ----- -----

20 3.080 3.056 ----- -----

22 2.880 2.856 ----- -----

24 2.656 2.630 ----- -----

(-----) unavailable

SCH 10S
inches

SCH 40S
inches

SCH 80S
inches

H= ___________

"H"

alignment rod

process pipe

H Dimensions, Hot-Tap Sensors (2540-3, 2540-4)

Wrought Steel Pipe Per ANSI 36.10

NPS

SCH 40

inches

inches

1 ½ 15.084 15.040 15.084 15.040

2 15.029 14.978 15.029 14.978

2 ½ 14.940 14.882 14.940 14.882

3 14.867 14.800 14.867 14.800

3½ 14.809 14.736 14.809 14.736

4 14.750 14.670 14.750 14.670

5 14.627 14.534 14.627 14.534

6 14.534 14.382 14.534 14.382

8 14.270 14.128 14.270 14.128

10 14.023 13.840 14.023 13.915

12 13.790 13.565 13.815 13.715

14 13.640 13.390 13.690 13.590

16 13.390 13.115 13.490 13.390

18 13.140 12.840 13.290 13.190

20 12.915 12.565 13.090 12.990

22 ----- 12.290 12.890 12.790

24 12.440 12.015 12.690 12.590

6

Signet 2540 High Performance Flow Sensor

SCH 80
inches

STD
inchesXSinches

pipe side view

(-----) unavailable

Stainless Steel Pipe Per ANSI B36.19

NPS
inches

SCH 5S
inches

SCH 10S
inches

SCH 40S
inches

SCH 80S
inches

1 ½ 15.148 15.113 15.084 15.040

2 15.101 15.065 15.029 14.978

2 ½ 15.036 15.007 14.940 14.882

3 14.974 14.944 14.867 14.800

3 ½ 14.924 14.894 14.809 14.736

4 14.874 14.844 14.750 14.670

5 14.747 14.727 14.627 14.534

6 14.640 14.620 14.534 14.382

8 14.440 14.409 14.270 14.128

10 14.208 14.183 14.023 13.915

12 13.990 13.971 13.815 13.715

14 13.865 13.840 ----- -----

16 13.658 13.640 ----- -----

18 13.458 13.440 ----- -----

20 13.240 13.216 ----- -----

22 13.040 13.016 ----- -----

24 12.816 12.790 ----- -----

direction
of flow

lower hex nuts
(3/16 x 1/4-20)

jam nuts
(5/32 x 1/4-20)

359 mm

(14.14 in.)

sensor
fitting

UNDER PRESSURE!

alignment
rod

sensor
flange

process pipe
(top view)

The flow sensor alignment rod MUST be
parallel to the process pipe as shown.

flow direction

Standard Sensor Installation

A. Thread one hex nut onto each of the three threaded rods

included in package. Install threaded rod with a lock
washer onto the sensor fi tting. Secure rods in place by
tightening each hex nut against the sensor fi tting. (Fig. 4)

B. Thread one jam nut and lower hex nut onto each threaded

rod so that the top surface of each nut is at the proper "H"
dimension for your pipe. Secure each hex nut with a jam
nut. (Fig. 5)

C. Insert the fl ow sensor into the sensor fi tting, making

sure the alignment hole on the sensor fl ange is pointing
downstream.

D. Place the alignment rod in the alignment hole on the

sensor fl ange. Align the fl ange so rod is parallel to the
process pipe. (Fig. 6)

E. Thread upper hex nuts with lock washers until they contact

the sensor fl ange and tighten. Check for proper "H"
dimension and readjust if necessary. (Fig. 7)

hex nut

Lock washer

sensor fitting

Fig. 4 Fig. 5

Fig. 6

"H"

lower hex nuts
(3/16 x 1/4-20)

jam nuts
(5/32 x 1/4-20)

hex nut &
lock washer

sensor fitting

process pipe

Hot-Tap Sensor Installation

A. Thread one hex nut onto each of the three threaded rods

included in package. Install threaded rod with a lock
washer onto the sensor fi tting. Secure rods in place by
tightening each hex nut against the sensor fi tting. (Fig. 4)

B. Thread one jam nut and lower hex nut onto each threaded

rod so that the top surface of each nut is 359 mm
(14.14 in.) from the top surface of the sensor fi tting.
Secure each hex nut with a jam nut. (Fig. 8)

CAUTION: This setting is critical to ensure an
adequate sensor seal and to prevent the rotor
from hitting the isolation valve orifi ce
during installation.

C. Wipe the sensor body with a dry, clean cloth. Orient the

alignment hole on the sensor fl ange to point downstream.
Place the slotted fl ange over the threaded rods. Lower the
sensor into the fi tting until the sensor fl ange rests on the
lower hex and jam nuts.

D. Secure the sensor with lock washers and upper hex nuts

on the top of the fl ange. Before tightening, align the
sensor fl ange so that the alignment rod is parallel and level
with the process pipe. (Fig. 6 & Fig. 9)

E. Make sure the bleed valve is closed

(full clockwise position).

sensor
flange

jam nuts

sensor

"H"

fitting

Fig. 7

FLOW

sensor flange

cap nuts

upper hex nuts
& lockwashers

lower hex nuts

female pipe fitting

process
pipe wall I.D.

lower hex nut
and jam nuts

18 inch
threaded rods

sensor
fitting

Fig. 8

Upper hex nuts
(3/16 x 1/4-20)

1/4 in. lock
washers

alignment rod

359 mm (14.14 in)

bleed valve

direction
of flow

process pipe (side view)

Fig. 9

Signet 2540 High Performance Flow Sensor

7

Hot-Tap Sensor Installation - Continued

F. Thread protector plate hex nuts onto each of the three

threaded rods. Adjust each hex nut to a height of
approximately 25 mm (1 in.) from the top of each rod.
(Fig. 10)

G. Position the installation tool bearing plate by rotating it

so that it is approximately 40 mm (1.6 in.) from the swivel
mount. Mount the installation tool by placing the threaded
rods through the holes in the tool's bearing plate, resting
the bearing plate on top of the protector plate hex nuts.
Make sure the swivel mount's ears are mounted between
the threaded rods (not over the rods). Install the bearing
plate cap nuts. Tighten the bearing plate cap nuts to
secure the installation tool in place. (Fig. 11)

H. Align the sensor cable with the swivel mount cable port to

prevent cable pinching. Use a 3/8 inch wrench or socket
to turn the installation tool shaft clockwise until it is seated
in the hole at the top of the sensor fl ange.

I. Wearing safety face protection, slowly

open the isolation valve to the full open
position. Loosen the lower hex and jam nuts

and move them to the proper "H" dimension.
Turn the installation tool shaft clockwise until the sensor
fl ange contacts the lower hex and jam nuts. Thread the
upper hex nuts down until they contact the sensor fl ange.
Tighten the upper hex nuts to secure the sensor. (Fig. 12)

Fig. 10

Fig. 11

protector plate
cap nuts

25 mm
(1.0 in.)

cap nuts

protector plate

hex nuts

sensor

cable

protector plate
removed during
sensor installation

protector plate
hex nut (3/16 x ¼ -20)

installation tool
threaded shaft

bearing plate

swivel mount
w/cable port

sensor flange

sensor body

J. Remove cap nuts and withdraw the installation tool. Be

careful to not damage cable. Replace protector plate and
cap nuts. (Fig. 13)

Standard Sensor Removal

To remove the sensor from a depressurized empty pipe,
simply remove the cap nuts and upper hex nuts located
above the sensor fl ange. Pull up on sensor fl ange with
twisting motion.

Fig. 12

installation
tool shaft

upper hex nuts

"H"

direction
of flow

cap nuts

alignment rod

lower hex nuts

jam nuts

isolation valve

protector plate
cap nuts

protector plate

protector plate

Fig. 13

8

Signet 2540 High Performance Flow Sensor

hex nut

Rotor Pin

Hot-Tap Sensor Removal

To remove the Hot-Tap sensor safely from a pressurized active pipe,
the entire installation process must be reversed.

A. Remove the cap nuts, protector plate and protector plate hex nuts. (Fig. 14)

B. Thread installation tool in place and secure bearing plate in place of sensor

protector plate. (Fig. 15)

C. Turn shaft of installation tool clockwise to lower tool into opening in sensor fl ange.

Guide cable into the port to prevent damage.

D. Wearing safety face protection, loosen the upper hex nuts and raise to 372 mm

(14.6 in.) from top of sensor fi tting to bottom of upper hex nuts/lock washers.

CAUTION! This measurement is critical to maintain watertight

seal in sensor while allowing clearance to close the isolation valve.

E. Wearing safety face protection, turn the installation tool shaft counterclockwise to

withdraw sensor until the sensor fl ange contacts the upper hex nuts. (Fig. 16)

F. Raise one lower hex and jam nut to bottom of sensor fl ange.

G. Close isolation valve, remove bearing plate and tool.

H. Wearing safety face protection, cover the bleed valve with suitable protection

(rag, towel, etc.) and open the bleed valve (ccw rotation) to relieve internal
pressure. Pull sensor up until bleed valve purges some fl uid (indicating sensor
is past 1st o-ring seal inside sensor fi tting).

Fig. 14

Fig. 15

installation tool
threaded shaft

upper hex nuts
and lock washers

sensor flange

372 mm

(14.6 in.)

UNDER PRESSURE!

process pipe (side view)

protector plate
cap nuts

protector plate

protector plate
hex nut

lower hex and
jam nuts

sensor fitting

isolation valve

CAUTION: In case of a leaky isolation valve, the sensor will be under

a slight amount of pressure. Care should be taken when removing the
sensor. Use the bleed valve to relieve this pressure taking care not to
spray fl uid on yourself or others.

Sensor can now be safely removed. When reinstalling the sensor: leave one

lower hex nut in position to guide sensor to proper isolation valve clearance height
before opening isolation valve. Return to "H" dimension height after valve is opened.

Maintenance

Your sensor requires little or no maintenance of any kind, with the exception of an occasional
sensor/paddlewheel cleaning.

Rotor Replacement Procedure

3. Insert the new rotor assembly and

1. With a small pair of needle­nose pliers, fi rmly grip the
center of the rotor pin (axle)
and with a twisting motion,
bend the rotor pin into an
"S" shape. This should pull
the ends of the pin out of the
retainers and free the rotor
assembly.

2. Remove retainer from each
side by gently tapping it
inwards using a punch. Install
a new retainer with its rotor pin
clearance hole inward. Only
install one retainer at this time.

Retainer

Punch

bearings into the rotor housing
of the sensor and place the new
rotor pin (axle) through the open
end of the rotor housing, through
the rotor and bearings, and into
the previously installed retainer.

4. Using a vise or C-clamp, press
the second retainer into the hole
in the sensor body while lining up
the rotor pin with the center of the
retainer hole.

Note: A hammer and center

punch can also be used if a
clamp or vise is not available.

cap nuts

protector plate

hex nuts

upper hex nuts

Fig. 16

Existing
Retainer

installation tool
threaded shaft

installation tool
bearing plate

swivel mount
w/cable port

sensor flange
1 lower hex nut

and jam nut

sensor body

Rotor Pin

Rotor
Assembly

New
Bearings

Signet 2540 High Performance Flow Sensor

9

K-Factors (Stainless Steel, Wrought Steel & Plastic Pipe)

SCH 5S STAINLESS STEEL PIPE
PER ANSI B36.19

K-Factor
PIPE
SIZE

1½ in. 115.1900 30.433
2 in. 71.3960 18.863
2 ½ in. 49.263 13.015
3 in. 32.636 8.622
3 ½ in. 24.537 6.483
4 in. 19.1350 5.055
5 in. 12.4490 3.289
6 in. 8.4602 2.235
8 in. 4.9137 1.298
10 in. 3.1228 0.825
12 in. 2.1772 0.575
14 in. 1.7977 0.475
16 in. 1.3717 0.362
18 in. 1.0855 0.287
20 in. 0.8801 0.233
22 in. 0.7293 0.193
24 in. 0.6141 0.162

PULSES/
U.S. GAL

K-Factor

PULSES/

LITER

XS WROUGHT STEEL PIPE
PER ANSI B36.10

K-Factor
PIPE
SIZE

1 ½ in. 161.79 42.745
2 in. 95.713 25.287
2 ½ in. 66.686 17.618
3 in. 42.986 11.357
3 ½ in. 31.983 8.450
4 in. 24.668 6.517
5 in. 15.480 4.090
6 in. 10.691 2.825
8 in. 5.9733 1.578
10 in. 3.6489 0.964
12 in. 2.4548 0.649
14 in. 1.9931 0.527
16 in. 1.4970 0.396
18 in. 1.1727 0.310
20 in. 0.9388 0.248
22 in. 0.7685 0.203
24 in. 0.6446 0.170

PULSES/
U.S. GAL

K-Factor

PULSES/

LITER

SCH 40S STAINLESS STEEL PIPE
PER ANSI B36.19

K-Factor
PIPE
SIZE

1 ½ in. 140.030 36.996
2 in. 83.240 21.992
2 ½ in. 59.034 15.597
3 in. 38.675 10.218
3 ½ in. 28.752 7.596
4 in. 22.226 5.872
5 in. 14.061 3.715
6 in. 9.5160 2.514
8 in. 5.4523 1.441
10 in. 3.4507 0.912
12 in. 2.3318 0.616

SCH 40 STAINLESS STEEL PIPE

14 in. 1.9556 0.517
16 in. 1.4970 0.396
18 in. 1.1900 0.314
20 in. 0.9577 0.253
24 in. 0.6662 0.176

PULSES/

U.S. GAL

K-Factor
PULSES/

LITER

SCH 10S STAINLESS STEEL PIPE
PER ANSI B36.19

K-Factor
PIPE
SIZE

1½ in. 127.930 33.799
2 in. 76.439 20.195
2 ½ in. 51.946 13.724
3 in. 34.174 9.029
3½ in. 25.571 6.756
4 in. 19.829 5.239
5 in. 12.730 3.363
6 in. 8.5938 2.270
8 in. 5.0062 1.323
10 in. 3.1793 0.840
12 in. 2.1914 0.579
14 in. 1.8147 0.479
16 in. 1.3798 0.365
18 in. 1.0912 0.288
20 in. 0.8855 0.234
22 in. 0.7334 0.194
24 in. 0.6175 0.163

K-Factors are listed in U.S. gallons and in liters. Conversion
formulas for other engineering units are listed below.

• K = 60/A The K-Factor is the number of pulses

PULSES/
U.S. GAL

generated by the 2540 paddlewheel per unit of
liquid in a specifi c pipe size.

K-Factor

PULSES/

LITER

STD WROUGHT STEEL PIPE
PER ANSI B36.10

PIPE
SIZE

1 ½ in. 140.030 36.996
2 in. 83.240 21.992
2 ½ in. 59.034 15.597
3 in. 38.674 10.218
3 ½ in. 28.752 7.596
4 in. 22.226 5.872
5 in. 14.061 3.715
6 in. 9.5160 2.514
8 in. 5.4523 1.441
10 in. 3.4507 0.912
12 in. 2.3318 0.616
14 in. 1.9186 0.507
16 in. 1.4483 0.383
18 in. 1.1390 0.301
20 in. 0.9146 0.242
22 in. 0.7506 0.198
24 in. 0.6311 0.167

K-Factor
PULSES/
U.S. GAL

SCH 40 WROUGHT STEEL PIPE
PER ANSI B36.10

K-Factor

PULSES/

LITER

To convert multiply

K from: to: K by:

U.S. gallons cubic feet 7.479

U.S. gallons cubic inches 0.00433

U.S. gallons cubic meters 263.85

U.S. gallons pounds of water 0.120

U.S. gallons acre feet 325853

U.S. gallons Imperial gallons 1.201

PIPE
SIZE

1 ½ in. 140.030 36.996
2 in. 83.240 21.992
2- ½ in. 59.034 15.597
3 in. 38.674 10.218
3 ½ in. 28.752 7.596
4 in. 22.226 5.872
5 in. 14.061 3.715
6 in. 9.5160 2.514
8 in. 5.4523 1.441
10 in. 3.4507 0.912
12 in. 2.3517 0.621
14 in. 1.9556 0.517
16 in. 1.4970 0.396
18 in. 1.1900 0.314
20 in. 0.9577 0.253
24 in. 0.6662 0.176

K-Factor
PULSES/
U.S. GAL

K-Factor
PULSES/
LITER

10

Signet 2540 High Performance Flow Sensor

K-Factors (Stainless Steel, Wrought Steel & Plastic Pipe) continued

SCH 80S STAINLESS STEEL PIPE
PER ANSI B36.19

K-Factor

PIPE

SIZE

1 ½ in. 161.790 42.745
2 in. 95.710 25.287
2 ½ in. 66.686 17.618
3 in. 42.986 11.357
3 ½ in. 31.983 8.450
4 in. 24.668 6.517
5 in. 15.480 4.090
6 in. 10.691 2.825
8 in. 5.9733 1.578
10 in. 3.6489 0.964
12 in. 2.4548 0.649

SCH 80 STAINLESS STEEL PIPE

14 in. 2.1557 0.570
16 in. 1.6444 0.434
18 in. 1.3036 0.344
20 in. 1.0533 0.278
22 in. 0.8689 0.230
24 in. 0.7335 0.194

PULSES/
U.S. GAL

K-Factor

PULSES/

LITER

SCH 80 WROUGHT STEEL PIPE
PER ANSI B36.10
PIPE

SIZE

1 ½ in. 161.790 42.745
2 in. 95.713 25.287
2 ½ in. 66.686 17.618
3 in. 42.986 11.357
3 ½ in. 31.983 8.450
4 in. 24.668 6.517
5 in. 15.480 4.090
6 in. 10.691 2.825
8 in. 5.9733 1.578
10 in. 3.7983 1.004
12 in. 2.6198 0.692
14 in. 2.1557 0.570
16 in. 1.6444 0.434
18 in. 1.3036 0.344
20 in. 1.0533 0.278
22 in. 0.8689 0.230
24 in. 0.7335 0.194

K-Factor
PULSES/
U.S. GAL

K-Factor
PULSES/
LITER

SCH 40 Plastic pipe per ASTM-D-1785

K-Factor
PIPE
SIZE

1 ½ in. 139.850 36.948
2 in. 82.968 21.920
2 ½ in. 60.194 15.903
3 in. 39.513 10.439
3 ½ in. 29.295 7.740
4 in. 22.565 5.962
5 in. 14.308 3.780
6 in. 9.8630 2.606
8 in. 5.6400 1.490
10 in. 3.4476 0.911
12 in. 2.3786 0.628

PULSES/
U.S. GAL

K-Factor

PULSES/

LITER

SCH 80 Plastic pipe per ASTM-D-1785

K-Factor

PIPE

SIZE

1 ½ in. 162.290 42.877
2 in. 97.186 25.677
2 ½ in. 68.559 18.113
3 in. 43.870 11.590
3 ½ in. 32.831 8.674
4 in. 25.250 6.671
5 in. 15.835 4.184
6 in. 11.041 2.917
8 in. 6.2877 1.661
10 in. 3.8529 1.018
12 in. 2.6407 0.698

PULSES/
U.S. GAL

K-Factor

PULSES/

LITER

Signet 2540 High Performance Flow Sensor

11

Ordering Information

Signet 3-2540-XX Stainless Steel High Performance fl ow sensor with removable electronics

Mfr. Part No. Code Description

3-2540-1 198 840 035 1½ inch NPT thread, Tungsten Carbide rotor

3-2540-2 198 840 036 1½ inch ISO thread, Tungsten Carbide rotor

3-2540-3 198 840 037 1½ inch NPT thread, hot tap design, Tungsten Carbide rotor*

3-2540-4 198 840 038 1½ inch ISO thread, hot tap design, Tungsten Carbide rotor*

3-2540-1S 159 001 501 1½ inch NPT thread, Stainless Steel rotor

3-2540-2S 159 001 502 1½ inch ISO thread, Stainless Steel rotor

3-2540-3S 159 001 503 1½ inch NPT thread, hot tap design, Stainless Steel rotor*

3-2540-4S 159 001 504 1½ inch ISO thread, hot tap design, Stainless Steel rotor*

*Must use 3-1500.663 Hot-Tap installation tool (ordered separately)

Accessories and Replacement Parts

3-1500.663 198 820 008

1220-0021 198 801 000 O-ring, FKM

1224-0021 198 820 006 O-ring, EPDM

1228-0021 198 820 007 O-ring, FFKM

3-2540.320 198 820 040

3-2540.321 159 000 623 Rotor Kit, 2540 Tungsten Carbide Pin

3-2540.322 159 000 864 Rotor kit, Stainless Steel pin

P52504-3 159 000 866 Rotor pin, Tungsten Carbide

P52504-4 159 000 867 Rotor pin, 316 SS

P52503 198 820 013 Bearing, carbon reinforced PTFE

3-2540.520 159 000 648 Bearing, PTFE

P52527 159 000 481 Retainers, SS (1.4401)

3-2541.260-1 159 000 849 Standard replacement electronics module

3-2541.260-2 159 000 850 Hot-Tap replacement electronics module

5523-0222 159 000 392 Cable, per ft.

P51589 159 000 476 Conduit Adapter Kit

P31934 159 000 466 Conduit Cap

Hot-Tap Installation Tool

Rotor kit, 2540 PEEK® Bearing (old version)

Georg Fischer Signet LLC, 3401 Aero Jet Avenue, El Monte, CA 91731-2882 U.S.A. • Tel. [phone] • Fax [phone]
For Worldwide Sales and Service, visit our website: www.gfsignet.com • Or call (in the U.S.): [phone]
For the most up-to-date information, please refer to our website at www.gfsignet.com

3-2540.090 Rev. 10 01/19 English © Georg Fischer Signet LLC 2019