FT2 Turbine Flow Meter Instructions
Optical Detection Turbine Flow Sensor- Installation Notes
Hall Detection Turbine Flow Sensor – Installation Notes
Titan Flowmeters: FT2 optical detection flow turbine meter: Instruction Sheet
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 cavitation 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 ultra-pure water. Custom fittings are available for OEM use.
Titan FT2 Turbine Flow Meter: Optical Detection: 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 instrument, 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.
FT2 optical detection flow turbine meter – Electrical Characteristics
- FT2 Optical detector Turbine Flow Meter
- Supply voltage: 7.5 – 24Vdc
- Temp range: -10 to 60°C
- Switch Voltage: 24 max
- Switch current: 20mA max
- Supply current: 25mA max
- FT2 Hall detector Turbine Flow Meter
- Supply voltage: 4.5 – 24Vdc
- Temp range: -25 to 125°C
- Supply current 7.5mA typ
- Rise & Fall Times: 1.5uS max
- Switch current: 10mA max
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 a 10K Ohm 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.
|Problem||Reading (low)||Reading (high)||Reading (Erratic)||Action required|
|1.Air in system |
3. Flow disturbance
4. Poor connections
5. Debris in meter
6. Opaque fluid
7. Incorrect inst cal
8. Blocked filter
|1. Check plumbing raise back pres. |
2. Distance pump—provide damping
3. Re-site flowmeter or disturber
4. Check all terminations and wiring
5. Clean meter – install filter
6. Use Hall effect flowmeter
7. Re-set instrument and recalibrate
8. Replace filter element
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 |
|Filter, pump |
or 1 bend
or 2 bends
|2 bends |
|10 – 160||15||50||100|
|1 – 10||10||15||50|
|0 – 1||5||10||15|