GF Signet 2540 User manual

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
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.
Recommended sensor upstream/downstream mounting requirements.
+30°
0°
Process Pipe
- 30°
Signet 2540 High Performance Flow Sensor
English
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
Operating Instructions
Location of Fitting
Table of Contents
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• 中文
*3-2540.090*
3-2540.090 Rev. 10 01/19
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.
Sensor Mounting Position

2Signet 2540 High Performance Flow Sensor
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.
Note / Technical Notes
Highlights additional information or detailed procedure.
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,
chemical poisoning, dry-out) or
mishandling (e.g. broken glass,
damaged membrane, freezing
and/or extreme temperatures).
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
Warranty Information
Product Registration
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.
Paddlewheel Maintenance
Standard Sensor Dimensions:
2540-1(S) = 1½ in. NPT fi tting
2540-2(S) = IS0 7-R 1½ fi tting
Hot-Tap Sensor Dimensions:
2540-3(S) = 1½ in. NPT fi tting
2540-4(S) = IS0 7-R 1½ fi tting
457 mm
(18 in.)
Adjustable
length
Sensor fitting:
1½ in. NPT or
ISO 7-R 1½ thread
24 mm (0.94 in.) dia.
64 mm (2.5 in.) dia.
Bleed
valve
7.6 m
(25 ft.)
cable
O-ring
seals (2)
Adjustable
length
7.5 m (25 ft.)
integral cable
24 mm (0.94 in.) dia.
64 mm (2.5 in.) dia.
127 mm
(5.0 in.)
Sensor fitting:
1½ in. NPT or
ISO 7-R 1½ thread
O-ring
seal (1)
Dimensions
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.

3
Signet 2540 High Performance Flow Sensor
Specifi cations
Note:
Pressure/temperature specifi cations refer to sensor
performance in water. Certain chemical limitations may apply.
Chemical compatibility should be verifi ed.
04/08
manufactured date code = mm/yy
ex. 04/08
04 - month of April
08 - year 2008
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)
Sensor Wiring
½ in. NPT conduit port
• Use 2-conductor shielded cable for cable extensions up to
300 m (1000 ft)
• Maintain cable shield through splice.
Black (5 to 24 VDC)
Silver (DC return)
Signet Instruments
Other Brands
Input
Gnd.
10 kΩ
+
5 to 24
VDC
-
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.
Other
instrument
Blk, sensor
power
Red, freq.
input
Shld,
Gnd
instrument
Red (signal out)
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.

4Signet 2540 High Performance Flow Sensor
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.
½ in. NPT Threads
Electronics Module
3-2541.260-1 (for Standard sensor)
3-2541.260-2 (for Hot-tap sensor)
Liquid Tight Connector-
Compression Fitting
w/ ½ in. NPT threads
Liquid Tight Connector-Cap
Grip the electronics
module at rubber strain
relief
NOTE: Apply thread sealant to the
liquid tight connector threads.

5
Signet 2540 High Performance Flow Sensor
process pipe
sensor fitting
bleed valve
make sure
bleed valve
clears isolation
valve handle
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.
D. Remove sensor fi tting from sensor assembly.
E. Thread sensor fi tting into pipe fi tting. (Fig. 1)
pipe
fitting
process
pipe
pipe sealant recommended
sensor
fitting
customer supplied
nipple: 40 x 50 mm
(1.50 x 2 in.) long
customer supplied
ball or gate valve
process pipe (side view)
Fig. 2
Fig. 3
Fig. 1
Installation
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.

6Signet 2540 High Performance Flow Sensor
"H"
alignment rod
sensor flange
process pipe
direction
of flow
pipe side view
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.: ___________
AB
1
2
3
4
5
6
1
2
3
4
5
AB
1
2
3
4
5
6
1
2
3
4
5
pipe I.D.
wall
thickness
AB
1
2
3
4
5
6
1
2
3
4
5
incorrect
correct
H Dimensions, Standard Sensors (2540-1, 2540-2)
Wrought Steel Pipe Per ANSI 36.10
NPS
inches
SCH 40
inches
SCH 80
inches
STD
inches
XS
inches
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
inches
SCH 5S
inches
SCH 10S
inches
SCH 40S
inches
SCH 80S
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 4.344 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 ----- -----
Wrought Steel Pipe Per ANSI 36.10
NPS
inches
SCH 40
inches
SCH 80
inches
STD
inches
XS
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
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 ----- -----
(-----) unavailable
(-----) unavailable
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: H= ___________
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.
H Dimensions, Hot-Tap Sensors (2540-3, 2540-4)
Calculating the H Dimension

7
Signet 2540 High Performance Flow Sensor
lower hex nut
and jam nuts
sensor flange
18 inch
threaded rods 359 mm (14.14 in)
process pipe (side view)
direction
of flow
alignment rod
Upper hex nuts
(3/16 x 1/4-20)
1/4 in. lock
washers
sensor
fitting bleed valve
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!
Fig. 8
Fig. 9
"H"
process
pipe wall I.D.
sensor
fitting
upper hex nuts
& lockwashers
lower hex nuts
jam nuts
sensor
flange
cap nuts
female pipe fitting
FLOW
alignment
rod
sensor
flange
process pipe
(top view)
The flow sensor alignment rod MUST be
parallel to the process pipe as shown.
flow direction
Fig. 6
Fig. 7
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)
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 fitting
hex nut
Lock washer
Fig. 4 Fig. 5
process pipe
lower hex nuts
(3/16 x 1/4-20)
jam nuts
(5/32 x 1/4-20)
"H"
sensor fitting
hex nut &
lock washer
Standard Sensor Installation
Hot-Tap Sensor Installation

8Signet 2540 High Performance Flow Sensor
protector plate
hex nut
protector plate
cap nuts
protector plate
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.
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)
J. Remove cap nuts and withdraw the installation tool. Be
careful to not damage cable. Replace protector plate and
cap nuts. (Fig. 13)
swivel mount
w/cable port
installation tool
threaded shaft
sensor flange
bearing plate
cap nuts
protector plate
hex nuts
sensor body
sensor
cable
Fig. 11
Fig. 12
Fig. 13
"H"
jam nuts
lower hex nuts
alignment rod
installation
tool shaft cap nuts
upper hex nuts
direction
of flow
isolation valve
25 mm
(1.0 in.) protector plate
hex nut (3/16 x ¼ -20)
protector plate
cap nuts protector plate
removed during
sensor installation
Fig. 10
Hot-Tap Sensor Installation - Continued
Standard Sensor Removal

9
Signet 2540 High Performance Flow Sensor
installation tool
threaded shaft
sensor flange
cap nuts
upper hex nuts
1 lower hex nut
and jam nut
sensor body
installation tool
bearing plate
protector plate
hex nuts
swivel mount
w/cable port
Fig. 16
Your sensor requires little or no maintenance of any kind, with the exception of an occasional
sensor/paddlewheel cleaning.
protector plate
hex nut
protector plate
cap nuts
protector plate
Fig. 14
installation tool
threaded shaft
process pipe (side view)
372 mm
(14.6 in.)
upper hex nuts
and lock washers
sensor flange
lower hex and
jam nuts
UNDER PRESSURE!
sensor fitting
isolation valve
Fig. 15
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).
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.
Rotor Replacement Procedure
1. With a small pair of needle-
nose 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.
Punch
Retainer
Rotor Pin
Rotor Pin
Existing
Retainer New
Bearings
Rotor
Assembly
3. Insert the new rotor assembly and
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.
Hot-Tap Sensor Removal
Maintenance

10 Signet 2540 High Performance Flow Sensor
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
SCH 5S STAINLESS STEEL PIPE
PER ANSI B36.19
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
XS WROUGHT STEEL PIPE
PER ANSI B36.10
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
STD WROUGHT STEEL PIPE
PER ANSI B36.10
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 40S STAINLESS STEEL PIPE
PER ANSI B36.19
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 40 WROUGHT STEEL PIPE
PER ANSI B36.10
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 10S STAINLESS STEEL PIPE
PER ANSI B36.19
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
generated by the 2540 paddlewheel per unit of
liquid in a specifi c pipe size.
K-Factors (Stainless Steel, Wrought Steel & Plastic Pipe)

11
Signet 2540 High Performance Flow Sensor
SCH 80S STAINLESS STEEL PIPE
PER ANSI B36.19
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 80 WROUGHT STEEL PIPE
PER ANSI B36.10
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 40 Plastic pipe per ASTM-D-1785
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
SCH 80 Plastic pipe per ASTM-D-1785
PIPE
SIZE
K-Factor
PULSES/
U.S. GAL
K-Factor
PULSES/
LITER
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
K-Factors (Stainless Steel, Wrought Steel & Plastic Pipe) continued

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
Hot-Tap Installation Tool
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 Rotor kit, 2540 PEEK® Bearing (old version)
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
Signet 3-2540-XX Stainless Steel High Performance fl ow sensor with removable electronics
Ordering Information
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