FT2 flow turbine meter Instruction Sheet
- FT2 Optical
- FT2 Hall Effect
- All fitting types
All turbine flowmeters require a fully formed upstream
flow profile. This is usually attained by positioning
the flow meter in a straight length of pipe
some distance from any component that is likely to
introduce an asymmetric or swirling velocity profile.
The chart below gives some indication of the
straight lengths of pipe expressed in pipe diameters
required for various site conditions.
Flow range
L/Min | Filter, pump
or 1 bend | Regulator
or 2 bends | 2 bends
@90° |
| 10 - 160 | 15 | 50 | 100 |
| 1 - 10 | 10 | 15 | 50 |
| 0 - 1 | 5 | 10 | 15 |
FT2 flow turbine meter - Eletrical Characteristics
Hall effect sensors
Supply voltage: 4.5-24Vdc
Temp range: -40 to150°C
Rise & fall times: 1.5uS max
Supply current: 7.5mA typ.
Switch current: 10mA max
Optical detector
Supply voltage: 7.5 - 24Vdc
Rise time: 1.5uS max
Switch Voltage: 24 max
Switch current: 20mA max
Supply current: 25mA max
|
Titan Flowmeters: FT2 flow turbine meter
The pipe work must be designed in such a way as to eliminate reverse flow,
and the flow passes through the meter in the direction of the arrow. The meter
should be installed in a position that prevents it from draining down as on
start-up serious damage could result by “impacting” an empty flowmeter with
a high velocity fluid stream. The fluid should be clean and homogenous and
in the case of optical detection, be able to transmit infra-red light. In all cases
an upstream filter of at least 80 microns must be fitted. It is recommended
that before the flowmeter is installed in the line a “dummy” section of
pipe is inserted and the system flushed. This is to eliminate any debris in
that section of the line. The pipe must not stress the body of the meter and
should be fully supported either side with appropriate isolation valves and in
some cases a by-pass valve. When screwing fittings into a threaded body always
place the second spanner next to the fitting being inserted, never
tighten one fitting against the other across the meter body. On initial start-up
increase the flow slowly to ensure no over speeding of the meter occurs as
the air is forced from the line. This is best achieved by monitoring the flow
rate and ensuring that a 50% over-range is not exceeded. Never blow a
flowmeter with an airline. Care should be taken to ensure that no air enters
the system (e.g. leaky pump gland) or that no cavitations takes place. With a
volatile liquid we recommend at least twice the vapour pressure plus 1 Bar as
the operating pressure. The user must ensure that the materials of construction
are compatible with their fluid. We accept no responsibility for material
compatibility, it is the users responsibility.
The principle of operation is very simple. A jet of low viscosity
liquid (less than 15cP) is directed at a free running Pelton wheel
turbine in a specially shaped chamber. The rotation of the rotor
is detected either optically or with a Hall effect sensor. The output
frequency of these pulses is directly proportional to flow rate
and the total number of pulses the total volume passed. The
standard bearing material is sapphire as this gives a long trouble
free life to the meter. Non-metallic options mean that these
meters may be used with very aggressive chemicals and ultrapure
water. Custom fittings are available for OEM use.
Titan Flowmeters: FT2 flow turbine meter electrical
It is recommended that all “signal” cables
are screened and run separately
to power lines and switched inductive
loads and are located well away from
inverters and other “noisy” apparatus.
Always use sound wiring practice.
Both Hall effect and optical detectors
(NPN) require an external pull-up resistor
connected between the output
and a suitable power supply to attain
a pulse. Typically the flowmeter PSU
may be used but sometimes a dc
pulse, which is of a different voltage,
may be required e.g. using a PLC with
a 24V PSU and an internal 5V rail for
the pull-up resistor/pulse input.
Titan Flowmeters: FT2 flow turbine meter commissioning
If problems occur during commissioning always check the fundamentals
first.
- Is the flowmeter/instrument the correct one for the
installation?
- Is the power connected to the meter and the instru
ment, and is it turned on?
- Is the instrument set/wired correctly? I/P port, pulse
type, frequency span, units etc.
- Where possible check the O/P from the flowmeter
with an oscilloscope before proceeding
- Was the line flushed prior to installing the meter?
- Was the flow increased slowly?
- Is the meter blocked?
If you cannot find a solution ask your supplier for technical support.
| Problem | Reading (low) | Reading (high) | Reading (Erratic)Action required |
Air in system
Pulsations
Flow disturbance
Poor connections
Debris in meter
Opaque fluid
Incorrect inst cal
Blocked filter |
*
*
*
*
*
*
|
*
*
*
*
*
*
|
*
*
*
*
*
*
|
Check plumbing raise back pres.
Distance pump—provide damping
Re-site flowmeter or disturber
Check all terminations and wiring
Clean meter - install filter
Use Hall effect flowmeter
Re-set instrument and recalibrate
Replace filter element
|
|
|
|
|
Product Directory
Insertion Turbine
Sight Flow Indicators
Calibration
