Thermo-Flo™ FT10 Series Manual

Introduction

Offered in liquid sensor types, the general purpose flow switch provides reliable low or no-flow detection of relatively clean, non-coating media with one 1A relay output. Liquid examples include water and acetic acid. Available in Polypropylene-Ryton® or PVDF, the short flow sensor is used in pipe or ducting from ½” to 1-1/2", and the long flow sensor is used in 2" and up. The flow switch set point may be adjusted from 0.04 to 3 fps in liquids as a low-flow alarm. The flow sensor is best applied in applications with relatively constant temperatures.

NEW FEATURES

• Rugged Polypropylene-Ryton® or PVDF sensor for corrosive liquids.
• Adjustable set point with LED for flow or no-flow status indication.
• 60VA relay selectable NO or NC via power supply wiring polarity.
• Solid State sensor is not damaged by over-ranging flow velocities.

Specifications

Dimensions

Long Sensor (FT10 - _ 4 _ _)

Includes diagram showing dimensions and wire connections (Red: +, Black: -, White: NO/NC, Green: COM, Shld). Cable length: 10' (3m).

Short Sensor (FT10 - _ 3 _ _)

Includes diagram showing dimensions and wire connections (Red: +, Black: -, White: NO/NC, Green: COM, Shld). Cable length: 10' (3m).

DERATING CHARTS

Includes three charts:

• Temperature/Pressure Derating: Shows acceptable and unacceptable ranges for temperature vs. pressure.
• Maximum Temperature/Voltage Derating @ Maximum Current: Shows acceptable and unacceptable ranges for ambient sensor temperature vs. operating voltage.
• Flowline Electrical Loading Limits: Shows acceptable and unacceptable ranges for supply voltage vs. max. series resistance.

Safety Precautions

About this Manual: READ THE ENTIRE MANUAL PRIOR TO INSTALLING OR USING THIS PRODUCT. Refer to the part number on the switch label to verify the exact model configuration.

User's Responsibility for Safety: It is the user's responsibility to select a sensor model appropriate for the application, install it properly, perform tests, and maintain all components. Failure to do so could result in property damage or serious injury.

Proper Installation and Handling: Only properly trained staff should install and/or repair this product. Use a proper sealant with all installations. Always install the 3/4” Viton gasket with all versions of Thermo-Flo™™ with metric threads. Never overtighten the sensor within the fitting, beyond a maximum of 80 inch-pounds torque. Always check for leaks prior to system start-up.

Material Compatibility: FT10 series sensors are available in Polypropylene (PP) with Ryton® tips or Polyvinylidene Fluoride (PVDF). Ensure the selected model is compatible with the application liquid. Refer to the Compass Corrosion Guide for chemical compatibility.

Wiring and Electrical: Supply voltage is 14 to 36 VDC. Electrical wiring must be performed in accordance with all applicable national, state, and local codes.

Flammable, Explosive or Hazardous Applications: DO NOT USE THE FT10 SERIES GENERAL PURPOSE FLOW SWITCHES IN HAZARDOUS LOCATIONS.

Handling Static-Sensitive Circuits/Devices: Follow guidelines to reduce electrostatic charge build-up:

1. Always touch a known good ground source before handling the part. Repeat while handling and after sitting down, sliding across a seat, or walking a distance.
2. Avoid touching electrical terminals unless making connections.

Make a Fail-Safe System: Design a fail-safe system accounting for switch and/or power failure. FLOWLINE recommends redundant backup systems and alarms.

Flow Switch Models

Thermo-Flo™ is offered in two different models. The table below shows the available configurations:

Note: Part numbers with a -25 or -50 at the end indicate switches with extended cable (e.g., FT10-1305-25 is a flow switch with 25' of cable).

Getting Started

Technology

The thermal dispersion flow switches measure liquid temperature to determine changes in flow velocity. As fluid flows across the sensing tips, the temperature is reduced proportionately as a function of the flow rate. When a temperature or velocity shift reaches the user-defined set point, the switch changes state indicating the appropriate flow condition (flow or no-flow).

Flowline's sophisticated electronics convert the temperature shift into a signal which indicates whether a flow or no-flow condition occurs. Depending on how the sensor is wired, this signal may be wired for normally open or normally closed circuits.

Flowline's Thermo-Flo™™ flow switches have no moving parts to clog or foul, making them suitable for a variety of applications, including non-coating and non-scaling liquids. The FT10 series directly measure mass flow and can operate over a broad range of liquids from 0.4 to 1.2 specific gravity and 1 to 300 cp.

Initializing Sequence:

When the flow switch is powered up while submersed, the FT10 will immediately indicate flow before switching to its correct state. A time delay may be used to eliminate the initialization sequence. Flowline's thermal dispersion relay controllers feature a 0 to 60 second time delay.

Set Points:

The FT10 liquid flow switch set point is factory calibrated to 0.2 fps. To convert feet/sec to GPM, refer to the chart below.

FT10 Flow Rate vs. Velocity (gpm vs. fps)

Includes a graph illustrating the relationship between flow rate (gpm) and velocity (fps) for various pipe sizes.

Flow Switch Insertion and Orientation

The FT10 series flow switch must always be in contact with the liquid being measured. Flow switches feature a 3/4" NPT threads for use with various fittings. Ensure correct insertion depth after installation. The two sensor tips must be perpendicular to the flow; never mount the tips with one in front of the other.

Orientation and insertion depth are critical. The best location for installation is along the top of the pipe.

Warning: The flow switch tips have a thin plastic wall that may be damaged if dropped or installed improperly. Avoid installing the FT10 where bubbles are present or where the tips may be out of the liquid. Always install the Viton gasket with all versions of the FT10-_2_. The G threaded version will not seal unless the gasket is properly installed. The two temperature probes (tips) must always be perpendicular to the flow.

Wiring

Supply Voltage:

The supply voltage to the Thermo-Flo™™ flow switch should be between 14 VDC and 36 VDC.

Required Cable Length:

Determine the required cable length for easy installation, removal, and maintenance. Cable length can be extended up to 1000 ft using a well-insulated, 14 to 20 gauge shield 4-conductor cable.

Wire Stripping:

Using a 10 gauge wire stripper, carefully remove the outer layer of insulation from the last 1-1/4” of the sensor's cable. Unwrap and discard the exposed foil shield, leaving the drain wire attached if desired. With a 20 gauge wire stripper, remove the last 1/4” of the colored insulation from the signal wires.

Signal Output (Relay Switching):

The sensor can switch a small load directly using an internal relay rated below 60 VA. The NO/NC status is set by the polarity of the voltage feeding the red and black wires. The green wire is common for the relay, and the white wire is NO or NC depending on the polarity of red and black.

Normally Open Wiring: Diagram shows wiring for normally open configuration with a power supply and multimeter.

Wiring to a Flowline Controller:

Diagrams show wiring connections for the LC80 Series Controller and LC30 Series Controller, with the Thermo-Flo™™ sensor.

Wiring the Relay Output:

The Thermo-Flo™™ relay output can be wired as a dry contact to a VDC or VAC power source. The Thermo-Flo™™ requires 14-36 VDC power to operate the sensor and switch the relay. All installations below identify a dry switch state as the normal position of the relay.

• Switching a Normally Open DC Load (Open during Flow, Closed during No-Flow): Red wire to Positive (+), Black wire to Negative (-). Load attached to Green or White wires. Complete circuit by connecting Green to (+) VDC or White to (-) VDC. Diagram provided.
• Switching a Normally Closed DC Load (Closed during Flow, Open during No-Flow): Black wire to Positive (+), Red wire to Negative (-). Load attached to Green or White wires. Complete circuit by connecting Green to (+) VDC or White to (-) VDC. Diagram provided.
• Switching a Normally Open AC Load (Open during Flow, Closed during No-Flow): Red wire to Positive (+), Black wire to Negative (-). Load attached to Green wire and Hot of VAC power. White wire to Neutral of VAC power. Low voltage VAC is less than 36 VAC. Diagram provided.
• Switching a Normally Closed AC Load (Closed during Flow, Open during No-Flow): Black wire to Positive (+), Red wire to Negative (-). Load attached to Green wire and Hot of VAC power. White wire to Neutral of VAC power. Low voltage VAC is less than 36 VAC. Diagram provided.

For all Sensor Wiring diagrams above: Sensor Power: Red and Black Wires (36 VDC Max.). Relay Rating: Green and White Wires (60VA, 1A Max.).

Wiring as a P-Channel or N-Channel Output:

The Thermo-Flo™™ can be substituted for either a P-Channel (PNP, Sourcing) output or N-Channel (NPN, sinking) output.

• Normally Open DC Load as a P-Channel Output (Open during Flow, Closed during No-Flow): Red Wire to (+), Black wire to (-). Green wire jumping to Red wire. White wire connected to LOAD. Jumper LOAD back to Negative (-). Diagram provided.
• Normally Closed DC Load as a P-Channel Output (Closed during Flow, Open during No-Flow): Black wire to (+), Red wire to (-). Green wire jumping to Black wire. White wire connected to LOAD. Jumper LOAD back to Negative (-). Diagram provided.
• Normally Open DC Load as a N-Channel Output (Open during Flow, Closed during No-Flow): Red wire to (+), Black wire to (-). White wire jumping to Black wire. Green wire connected to LOAD. Jumper LOAD back to Positive (+). Diagram provided.
• Normally Closed DC Load as a N-Channel Output (Closed during Flow, Open during No-Flow): Black wire to (+), Red wire to (-). White wire jumping to Red wire. White wire connected to LOAD. Jumper LOAD back to Positive (+). Diagram provided.

For all Sensor Wiring diagrams above: Sensor Power: Red and Black Wires (36 VDC Max.). Relay Rating: Green and White Wires (60VA, 1A Max.).

Configuration

Set Point:

If the preset factory calibration is not adequate, follow the calibration steps. The switch's internal LED will be on when the switch detects no-flow and off when it detects flow, regardless of Red/Black wire polarity. Reversing Red/Black wires reverses relay polarity, not the internal LED.

1. Install the fitting and flow switch as described in the Installation section. Turn on the flow switch and controller power, and adjust the flow rate to the application setting. If the medium is subject to temperature variation, set the flow switch at the highest normal temperature likely to be encountered.
2. Locate the potentiometer knob at the top of the flow switch. The red LED is visible through the potentiometer. Adjustment is a single turn 270° potentiometer. Initial response time is 1 to 10 seconds. Adjust in slow increments and wait for the response.
• LED is ON: Adjust the potentiometer counterclockwise until the LED turns off.
• LED is OFF: Adjust the potentiometer clockwise until the light turns on.
3. Adjust the potentiometer back and forth where the LED is switching, settling where the LED is OFF (low flow state).
• If flow increases, the LED remains OFF (flow condition).
• If flow decreases, the LED turns ON (no-flow condition).
4. Verify new calibration: Lower system flow rate below the set point; the red LED should turn on. Increase flow rate above the set point; the red LED should turn off.

Includes a diagram showing the FT10 Flow Switch and Potentiometer Location.

Maintenance

General:

The Thermo-Flo™™ switch requires no periodic maintenance except to clean any deposits or scaling from the sensor tip as necessary. The user is responsible for determining the appropriate maintenance schedule based on the application liquids.

Cleaning Procedure:

1. Power: Ensure all power to the sensor, controller, and/or power supply is completely disconnected.
2. Sensor Removal: Ensure flow is off and pressure is down before removing the Thermo-Flo™™. Carefully remove the sensor. Replace with a 3/4" NPT plug to prevent leaks. Do not re-install if threads are damaged.
3. Cleaning the sensor: Use a soft bristle brush and mild detergent. Do not use harsh abrasives (steel wool, sandpaper) or incompatible solvents that may damage the sensor's PP/Ryton or PVDF plastic body.
4. Sensor Installation: Follow the installation steps outlined in the installation section.

Testing the Sensor:

1. Immersing the switch: Place the switch in a cup of water, ensuring the tips are submerged.
2. Power: Turn on power with Red to (+) and Black to (-). Polarity can be reversed.
3. No-Flow/Flow Test: With the switch in the cup, wait for the Red LED to turn ON (no-flow). Swirl the switch; the Red LED should turn OFF (flow). Stop swirling; the Red LED should turn ON again (no-flow). Repeat.
4. Relay Test: Connect a multimeter (set to Ohms) to the White and Green Wires. Perform the No-Flow/Flow test to observe relay actuation.
• With Red to (+) and Black to (-): Multimeter reads low resistance during no-flow (closed relay) and OL during flow (open relay).
• Reverse Polarity (Red to (-) and Black to (+)): Multimeter reads OL during no-flow (open relay) and low resistance during flow (closed relay).

The No-Flow/Flow test determines sensing capability. The Relay test determines the relay's ability to switch between no-flow and flow conditions.

Warranty, Returns and Limitations

Warranty:

Flowline warrants products to be free from defects in material and workmanship under normal use for two years from the date of manufacture. Flowline's obligation is limited to repair or replacement of defective products. Notification of any claim must be within thirty (30) days of claimed non-conformity. Repaired products are warranted for the remainder of the original warranty period. Replacement products are warranted for the full two years from the date of manufacture.

Returns:

Products cannot be returned without Flowline's prior authorization. Submit a customer return (MRA) request form at www.flowline.com. All returns must be shipped prepaid and insured. Flowline is not responsible for lost or damaged shipments.

Limitations:

This warranty does not apply to products that:

• Are beyond the warranty period or if warranty procedures were not followed.
• Have been subjected to electrical, mechanical, or chemical damage due to improper use.
• Have been modified or altered.
• Have been attempted to be repaired by unauthorized personnel.
• Have been involved in accidents or natural disasters.
• Are damaged during return shipment.

Flowline reserves the right to waive this warranty and dispose of any returned product if it contains hazardous material or remains unclaimed for more than 30 days after requested disposition.

This warranty is the sole express warranty. ALL IMPLIED WARRANTIES, INCLUDING MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED. Remedies are limited to repair or replacement. Flowline shall not be liable for incidental or consequential damages, including personal injury.

This warranty is the final, complete, and exclusive statement of warranty terms. No person is authorized to make other warranties or representations on behalf of Flowline.

This warranty will be interpreted pursuant to California law. If any portion is invalid, the rest remains in effect.

For complete product documentation, video training, and technical support, visit www.flowline.com. For phone support, call 562-598-3015 (8am-5pm PST, Mon-Fri). Please have the Part and Serial number available.