KELCO F26 Series User manual

The F26 series flow switch is a versatile heavy-duty paddle flow
switch suitable for detecting flow or no flow conditions in liquids
flowing in pipes of any diameter from 25mm upward. The
switch is available in two versions, a polypropylene model
designated F26-S, and a stainless body version designated
F26-SS. Both switches are identical with the exception of the
stainless body. The standard polypropylene switch is suitable
for most applications where static or dynamic pressures are
less than 18 Bars. The stainless version can safely tolerate
pressures to 100 Bars. The F26-SS has the advantage of higher
mechanical strength and finds application in fire prone or
vandal prone areas and is also suitable for marine use. Both of
the standard models are available with a high Amperage switch
capable of directly controlling single phase pump or fan motors,
to 1.5kW 2HP. These switches are designated F26-H
(polypropylene version) and F26-HS (316 stainless version).
Note: temperaturefor the maximum operating pressure shown in the above
operating environment table is 15°C, In the interest of safety, when using the
polypropylene version of the F26 series, maximum operating pressuremust be
de-rated linearly in direct proportion to temperature increase, to a maximum
pressure of 1 bar absolute at 80 degrees Centigrade. In other words only use
this switch at elevated temperatures in non pressurised systems that are
totally open to atmospherein all circumstances and under all conditions.
Select a location for the flow switch in a straight run of pipe
ideally with five pipe diameters of straight pipe either side of
the switch. This will ensure a linear non turbulent flow acts
against the paddle of the switch. Do not install the flow switch
in any location likely to expose it to excessive turbulence,
such as directly adjacent to valves or pumps, pipe bends or
elbows. The object is to achieve a smooth flow against the
paddle of the switch and thus obtain a stable non-chattering
response from the flow switch. The F26 flow switch can be
mounted in either the suction or discharge pipe of a pump, the
switch will respond equally well in a negative pressure
situation as well as in a positive pressure application.
The F26 flow switch is supplied with an extra long paddle
suitable for flow sensing in large diameter pipes. The paddle
will require trimming to allow installation in smaller diameter
pipes. The paddle can be cut and shaped as required using
tin snips or similar tools. See the accompanying table for
recommendations on paddle lengths. Note that the paddle
can be cut both in length and if required, in width. Many
installers maintain a more stable flow response can be
obtained by narrowing down the paddle, and thus avoiding
turbulence close to the walls of the pipe.
The F26 flow switch can be installed in either horizontal or
vertical piping, at right angles to the pipe, or at any angle up
to 45˚ off the vertical axis. Do not install the flow switch on the
underside of horizontal pipes, or in any orientation where
debris may accumulate in the pocket in the switch body and
ultimately prevent the switch from operating.
Asuitable 25mm (1”) B.S.P. female thread socket must be
provided to fit the flow switch. This may be a tapping saddle
or a pipe tee, or a socket welded directly to the piping. Ensure
that whatever fitting is used, sufficient clearance is allowed for
the free movement of the paddle. Normally a clearance to the
full inside diameter of the 1” B.S.P. thread (28mm) will be
required. The F26 flow switch can be installed in a one inch
B.S.P. socket attached to a short stand off pipe, at 90˚ to the
main pipe. This method increases the sensitivity of the switch
to low flows due to the extra leverage against the tip of a
longer paddle. If it is implemented, please ensure extra
clearance is allowed for the free radial movement of the
longer paddle.
Use thread tape or sealant and tighten the switch into the
socket using the spanner flats provided on the switch body.
Do not tighten the switch into its socket by twisting the switch
body,as damage to the flow switch may result. Align the flow
switch squarely to the axis of the pipe, with the direction of
flow arrow on the switch body pointing correctly and aligned
along the pipe. This flow switch will not function correctly
unless the alignment is correct.
When installing the flow switch in vertically running pipework,
note that the sensitivity of the switch will be slightly increased,
it will detect lower flows when flow is downward and will be
slightly decreased when flow is upward. This is due to the
effect of gravity and the dead weight of the paddle itself. This
effect is more noticeable in larger pipes and low flows where
long paddles may be used.
The F26 flow switch has a built in manual override, located
under the cable gland on the end face of the switch. The
rotary toggle switch is marked AUTO and ON. In the AUTO
position the flow switch responds solely to flow, and the
toggle switch has no effect. In the ON position the flow
switch is actuated regardless of the state of the actual flow,
that is, the switch is turned on. The override feature is handy
for testing new installations, commissioning systems and for
manually priming pumps or starting diesel pump sets etc. In
normal operation the override switch should be rotated fully
into the AUTO position. Do not operate the flow switch with
the override partly between auto and on, as it may not
function correctly.
INSTALLATION AND OPERATING INSTRUCTIONS FOR
F26 SERIES HEAVY DUTY FLOW SWITCHES
PLEASE READ THIS INSTALLATION SHEET CAREFULLY AND FULLY
BEFORE INSTALLING OR SERVICING THIS FLOW SWITCH.
INTRODUCTION
OPERATING ENVIRONMENT
INSTALLATION
Maximum operating pressure
(static or dynamic) at ambient
temperature.
Minimum burst pressure at
ambient temperature.
Maximum operating
temperature (Liquid)
Minimum operating temperature
(Liquid)
Process liquid Ph range
Ingress protection rating
(Housing)
CROSS SECTION OF
TYPICAL INSTALLATION
MANUAL OVERRIDE
18 Bars (260 PSI) polypropylene model
100 Bars (1450 PSI) Stainless model
80 Bars (1160 PSI) polypropylene
model
400 Bars (5800 PSI) Stainless model
80 Degrees C at a pressure 1 bar
absolute, see note below
-30˚C
1to 14
IP67

All electrical work associated with this flow switch
must be carried out by qualified persons only and
must be in accordance with the relevant local codes.
The F26 flow switch houses a magnetically coupled high
current high voltage single pole double throw
microswitch. Two versions are available, the F26-S which
is fitted with a 15Amp 500Volt switch suitable for most
general control circuit applications, and the F26-H which
is fitted with a 20Amp 500Volt switch capable of directly
controlling motors up to 1.5kW 2HP. The accompanying
table and sketch gives the electrical rating of the two
models, and the terminal designations.
In exposed locations ensure the lid and cable gland are
securely tightened and secondary precautions such as
cable drip loops are employed to ensure the ingress
protection rating of this switch is achieved.
Thereare two methods of setting the sensitivity of the
F26 flow switch. By far the most effective method is by
trimming the paddle. For fine tuning, a sensitivity
adjustment screw is provided, as shown in the
accompanying sketch. As supplied, the sensitivity screw
is wound fully in and is set to minimum sensitivity. The
adjusting screw can be wound out, and the sensitivity
slightly increased. The maximum effect is achieved with
the screw wound out to a point wherethe screw head is
flush with the base of the angled cowling.
The best effect is achieved by paddle trimming and this
is a compromise between sensitivity to the duty flow
and stress on the intruding paddle. Fluid flow
generates force, and a certain minimum amount of
force is required by the flow switch in order to function.
Excessive force however can bend or break paddles.
ELECTRICAL
PADDLE TRIMMING AND
FLOW SENSITIVITY
The accompanying table gives the flow in litres per minute required to
actuate the F26 flow switch when installed in Schedule 40 Steel Pipe
of various diameters. The flow rates given refer to water as the process
liquid. In the case of 25NB and 32NB pipe, the paddles aretrimmed
to clear the inside wall of the pipe by 3mm. For all other pipe diameters
the switch is fitted with a standardwidth paddle that has been trimmed
to the centre line of the pipe. The data is accurate to +/-15% in a non-
turbulent flow installation; with 5 diameters of straight pipe either side
of the switch. The accompanying table should be used as a
general guide only. Increasing the paddle length will proportionally
increase the sensitivity of the switch. That is it will decrease the flow
rate required to actuate the F26 flow switch. Inversely, decreasing the
paddle length will reduce the sensitivity of the switch and increase the
flow rate required to actuate the switch. Maximum recommended flow
rates aredetermined by setting a safe limit to the flow induced forces
acting on the paddle. Under the conditions described above the
maximum flow rates should not exceed 5 times the switching point flow
rates given in the table. Proportionally reducing the paddle length can
substantially increase the safe maximum flow rate, but at a low flow will
also increase the flow rate required to actuate the switch.
If the F26 flow switch is correctly installed and if the process fluid is
compatible with the materials of construction of this switch, then a
very long maintenance free service life can be expected. Factors
that may contribute to early failure of the F26 flow switch include
excess temperature, excessive pressure or electrical loads in excess
of the switch’s rating.
Pipe size 25NB 32NB 40NB 50NB 65NB 80NB 100NB 150NB 200NB
Switching point
on a rising flow 610 13 18 26 39 52 85 132
in L/Min
MAINTENANCE
MADE IN AUSTRALIA BY
KELCO Engineering Pty Ltd
ABN 20 002 834 844
Head office and factory
9/9 Powells Road Brookvale 2100 NSW Australia
Phone: [phone] Fax: [phone]
Email: [email protected] Web: www.kelco.com.au
©2008 Kelco Engineering Pty Ltd
PLEASE NOTE: Kelco Engineering Pty Ltd reserves the right to change the specification of this product without notice. Kelco Engineering Pty Ltd accepts
no liability for personal injury or economic loss as a consequence of the use of this product. All rights reserved copyright Kelco Engineering Pty Ltd © 2008.