Airflow Measurement System Installation Guide (Gen6)

This document provides instructions for installing the KMC Controls TrueFit Airflow Measurement System (Gen6). It covers the mounting of system components, connecting them to the controller, network connections, and power connections.

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Contents

• Example Diagrams
• Standard Application
• Outdoor Air Damper Pressure Assist Application
• Return Air Damper Pressure Assist Application
• Mounting the System Components
• Mounting the Controller
• Mounting the Inclinometer
• Mounting the Supply Airflow Pickup Tubes
• Mounting Pickup Tubes for Pressure Assist
• Mounting the Pressure Transducer(s)
• Mounting the OAT, RAT, and MAT Sensors
• Mounting a Proportional Actuator
• Connecting System Components to the Controller
• Connecting the Airflow Pickup Tubes
• Connecting the Pressure Transducer(s) to the Controller
• Connecting the Inclinometer
• Connecting the Outside Air Temperature Sensor
• Connecting the Return Air Temperature Sensor
• Connecting the Mixed Air Temperature Sensor
• Connecting the Proportional Actuator
• Connecting Networks
• Connecting an Ethernet Network
• Connecting an MS/TP Network
• Connecting Power
• Connecting Power to the Controller
• Connecting Power to the Inclinometer
• Connecting Power to the Pressure Transducer(s)
• Connecting Power to the Proportional Actuator
• Controller Power and Communication Status
• Controller MS/TP Network Isolation Bulbs
• Wiring Diagrams
• Input/Output Objects/Connections
• Configuring and Operating
• We Value Your Feedback!
• Important Notices

Example Diagrams

Standard Application

This section illustrates a standard application of the Airflow Measurement System.

The diagram shows a typical HVAC unit with components like the Outside Air Damper (OAD), Return Air Damper (RAD), Supply Air (SA) Pickup Tubes, Inclinometer, Outside Air Temperature (OAT) sensor, Return Air Temperature (RAT) sensor, Mixed Air Temperature (MAT) sensor, Pressure Transducer, and the AFMS Controller (TRF-5901C(E)-AFMS or TRF-9311C(E)-AFMS). A Proportional Actuator (MEP-4522/4952/7552) is also shown connected to the OAD.

Outdoor Air Damper Pressure Assist Application

This diagram depicts the system configured for Outdoor Air Damper (OAD) pressure assist. It includes the OAD, Inclinometer, OAT Sensor, SA Pickup Tubes, SA Pressure Transducer, RAT Sensor, MAT Sensor, and the AFMS Controller. A Proportional Actuator is connected to the OAD.

Return Air Damper Pressure Assist Application

This diagram illustrates the system for Return Air Damper (RAD) pressure assist. It shows the RAD, Inclinometer, RAT Sensor, SA Pickup Tubes, SA Pressure Transducer, OAT Sensor, MAT Sensor, and the AFMS Controller. A Proportional Actuator is connected to the RAD.

Mounting the System Components

Mounting the Controller

Note: Mount the controller inside a metal enclosure for RF shielding and physical protection.

Mounting Options:

• On a Flat Surface: Position the controller for easy terminal access. Secure with four #6 sheet metal screws through the corner mounting holes. The black terminals are for power, green for I/O, and grey for communication.
• On a DIN Rail: Position the DIN rail for easy terminal access. Pull out the DIN latch, position the controller with the top tabs on the rail, lower it, and push the DIN latch to engage.

Mounting the Inclinometer

Note: If the outside air damper has vertical-axis blades, install an HLO-1050 Linkage Kit first.

1. Position the inclinometer on a horizontal-axis damper blade (preferably outside air) with the wire parallel to the blades and the arrow sticker pointing up. If multiple outside air dampers exist, mount on a horizontal-axis return air damper blade. (An AFMS cannot be installed if there are multiple return air dampers.)
2. Attach the inclinometer with two #8 sheet metal screws.
3. Route the wire to avoid binding the damper and to prevent strain. Use wire ties for strain relief if necessary.

Mounting the Supply Airflow Pickup Tubes

Ensure enough pickup tubes are installed for accurate averaging. Multiple tubes (at least 2) in a parallel pitot array are recommended.

Mounting Methods:

• On the Supply Air Fan Bell (using SSS-1112/3/4 or SSS-1115/6/7): Position tubes so mounting feet span the fan inlet and all pickup points are within the airstream. Attach with self-tapping screws through the 3/16" mounting holes. Ensure pickup points are within the airstream for accurate averaging. Use shorter models if tubes are too long.
• In the Supply Air Duct (using SSS-101x): Mount in filtered air with laminar flow, approximately 6 straight duct diameters downstream. Install based on the flow arrow imprint, ensuring it points in the direction of airflow. Cut a 7/8" hole in the duct. Attach tubes with two self-tapping screws through the 3/16" mounting holes.

Mounting Pickup Tubes for Pressure Assist

Mounting for OAD Pressure Assist

Complete these steps for TRF-5901AC-AFMS or TRF-5901ACE-AFMS in an OAD pressure assist application.

1. Mount the first pickup tube outside the OAD in a location without turbulent flow (e.g., under the outside air hood). Install with the FLOW arrow imprint perpendicular to airflow (for static pressure). Mark the tube to indicate this orientation. Cut a 7/8" (22 mm) hole and attach with two self-tapping screws through the 3/16" (5 mm) mounting holes.
2. Mount the second pickup tube in the mixed air chamber, away from turbulent flow (e.g., inside the OAD, in a corner). Install with the FLOW arrow imprint perpendicular to airflow. Cut a 7/8" (22 mm) hole and attach with two self-tapping screws through the 3/16" (5 mm) mounting holes.

Mounting for RAD Pressure Assist

Complete these steps for TRF-5901AC-AFMS or TRF-5901ACE-AFMS in a RAD pressure assist application.

1. Mount the first pickup tube upstream of the return air damper. Install with the FLOW arrow imprint perpendicular to airflow. Cut a 7/8" (22 mm) hole and attach with two self-tapping screws through the 3/16" (5 mm) mounting holes.
2. Mount the second pickup tube downstream of the return air damper (in the mixed air side). Install with the FLOW arrow imprint perpendicular to airflow. Cut a 7/8" (22 mm) hole and attach with two self-tapping screws through the 3/16" (5 mm) mounting holes.

Mounting the Pressure Transducer(s)

Note: Complete these steps only if using a TRF-5901AC(E)-AFMS controller. Avoid locations with severe vibrations or excessive moisture.

CAUTION: Do not use in explosive or hazardous environments, or as a safety device where failure could cause injury.

1. Ensure adequate space for pressure and electrical connections.
2. Fasten the assembly to a location near the pickup tubes using screws through the case's mounting holes. Do not over-tighten.
3. If additional pickup tubes were installed for pressure assist, repeat steps 1 and 2 for a second pressure transducer near those tubes.

Mounting the OAT, RAT, and MAT Sensors

STE-1411/12/13/14 Bendable Copper Sensor

Use for easily-accessible mixed air sections and outside air hoods. A flexible cable sensor may be used if the mixed air section is not accessible. A rigid steel probe can be used for outside air hoods if not easily accessible.

1. Cut a hole in the mixed air chamber for the copper probe.
2. Insert the probe, bend it to cover the air path, and secure as needed. Maintain a minimum bend radius of 6 inches.
3. Fasten the enclosure to the unit using screws through the mounting holes.
4. Attach conduit to the 1/2" NPT threaded connection hole at the bottom of the enclosure for the cable to the AFMS controller.
5. Open the cover by pulling the latch and the cover.

STE-1415/6/7 Flexible Cable Sensor

Use if the mixed air section is not easily accessible.

1. Cut a hole in the mixed air chamber for the sensor cable.
2. Insert the cable, shape it to cover the air path, and secure as needed. Observe a minimum bend radius of 2 inches.
3. Fasten the enclosure to the unit using screws through the mounting holes.
4. Attach conduit to the 1/2" NPT threaded connection hole at the bottom of the enclosure for the cable to the AFMS controller.
5. Open the cover by pulling the latch and the cover.

STE-1404/05 Rigid Steel Probe

Use for the return air duct, or for the outside air duct if not easily accessible.

1. Locate the sensor in a straight duct section, away from heating/cooling/humidifier sources.
2. Cut a 1/4-inch hole for the probe and smaller holes for screws.
3. Insert the probe and fasten the assembly to the duct using screws through the housing mounting holes.
4. Open the sensor cover (STE-1404 only) by pulling the latch and the cover.
5. Attach conduit to the 1/2" NPT threaded connection hole at the bottom of the enclosure for the cable to the AFMS controller.

Mounting a Proportional Actuator

Complete these steps if a proportional actuator is not already mounted on the correct damper.

• Standard or OAD Applications: Mount on the outside air damper (or return air damper if it moves with the OAD).
• RAD Pressure Assist Applications: Mount on the return air damper (or outside air damper if it moves with the RAD).

For mounting instructions for MEP-series actuators (MEP-4552, MEP-4952, MEP-7552), refer to the specific model's installation guide available on the KMC Controls website.

Connecting System Components to the Controller

Connecting the Airflow Pickup Tubes

For a TRF-5901AC(E)-AFMS

Use appropriately sized polyethylene tubing. Minimize tubing length and arrange to prevent stress or kinking.

Connecting the Supply Airflow Pickup Tubes to the Pressure Transducer

1. Connect the Port Hs of all pickup tubes in parallel to the High input on the supply air pressure transducer.
2. Connect the Port Ls of all pickup tubes in parallel to the Low input on the supply air pressure transducer.

Connecting the Airflow Pickup Tubes for OAD Pressure Assist Applications

1. Connect one port of the pickup tube mounted outside the OAD to the High input on the pressure assist transducer. (It does not matter which port is used.)
2. Connect one port of the pickup tube mounted inside the OAD to the Low input on the pressure assist transducer. (It does not matter which port is used.)

Note: The other ports of these two pickup tubes are left unconnected and open to air.

Connecting the Airflow Pickup Tubes for RAD Pressure Assist Applications

1. Connect one port of the pickup tube mounted upstream of the return air damper to the High input on the pressure assist transducer. (It does not matter which port is used.)
2. Connect one port of the pickup tube mounted downstream of the return air damper to the Low input on the pressure assist transducer. (It does not matter which port is used.)

Note: The other ports of these two pickup tubes are left unconnected and open to air.

Connecting the Pressure Transducer(s) to the Controller

For a TRF-5901AC(E)-AFMS

1. Connect the signal wire from the transducer's OUT terminal to UI9 on the controller.
2. If a second transducer is used for pressure assist, connect its OUT signal wire to UI10 on the controller.

For a TRF-9311AC(E)-AFMS

Note: Use 1/4 inch (6.35 mm) FR tubing, maximum 20 feet (6 meters).

1. Remove the black shipping plugs from the PRESSURE SENSOR ports.
2. Connect the Port Hs of all pickup tubes in parallel to the HIGH port on the controller.
3. Connect the Port Ls of all pickup tubes in parallel to the LOW port on the controller.

Connecting the Inclinometer

1. Connect the yellow signal wire to UI7 on the controller.
2. Connect the green signal wire to UI8 on the controller.
3. Connect the blue ground wire to GND (between UI7 and UI8) on the controller.
4. Connect the red power wire to UO8 (TRF-5901AC[E]-AFMS) or U10 (TRF-9311AC[E]-AFMS).

Connecting the Outside Air Temperature Sensor

Note: Use 18 to 24 AWG shielded wiring. Do not run device wires in the same conduit with wires for inductive loads.

1. Feed the wire to the AFMS controller through the bottom hole.
2. Make connections using butt-splices or solder (wire nuts not recommended). The sensor is not polarity sensitive.
3. Plug the conduit with sealant to prevent air infiltration.
4. Close the door until latched. Install provided screws for added security if desired.
5. Connect the sensor's signal wire to UI4 on the controller.
6. Connect the sensor's ground wire to GND (next to UI4) on the controller.

Connecting the Return Air Temperature Sensor

Note: Use 18 to 24 AWG shielded wiring. Do not run device wires in the same conduit with wires for inductive loads.

1. Feed the wire to the AFMS controller through the bottom hole (if applicable).
2. Make connections using butt-splices or solder (wire nuts not recommended). The sensor is not polarity sensitive.
3. Plug the conduit with sealant to prevent air infiltration.
4. Close the door until latched (if applicable). Install provided screws for added security if desired (if applicable).
5. Connect the sensor's signal wire to UI5 on the controller.
6. Connect the sensor's ground wire to GND (next to UI5) on the controller.

Connecting the Mixed Air Temperature Sensor

Note: Use 18 to 24 AWG shielded wiring. Do not run device wires in the same conduit with wires for inductive loads.

1. Feed the wire to the AFMS controller through the bottom hole.
2. Make connections using butt-splices or solder (wire nuts not recommended). The sensor is not polarity sensitive.
3. Plug the conduit with sealant to prevent air infiltration.
4. Close the door until latched. Install provided screws for added security if desired.
5. Connect the sensor's signal wire to UI6 on the controller.
6. Connect the sensor's ground wire to GND (next to UI6) on the controller.

Connecting the Proportional Actuator

Using an Existing Proportional Actuator

CAUTION: Power off the actuator and other controller before proceeding.

1. Disconnect the signal and ground wires from the existing actuator's controller.
2. Connect the existing controller's signal wire to UI3 on the AFMS controller.
3. Connect the existing controller's ground wire to the GND terminal (next to UI3) on the AFMS controller.
4. Run a new signal wire from UO7 (TRF-5901AC[E]-AFMS) or UO9 (TRF-9311AC[E]-AFMS) to the actuator's signal terminal.
5. Connect the signal common wire of this new wire to the GND terminal (next to UO7/UO9) on the AFMS controller.

Using a New Proportional Actuator

For wiring instructions for MEP-series actuators (MEP-4552, MEP-4952, MEP-7552) to the controller, refer to the specific model's installation guide available on the KMC Controls website. Consult the Wiring Diagrams and Input/Output Objects/Connections sections for details on controller connections.

Connecting Networks

Connecting an Ethernet Network

For "E" models, connect an Ethernet patch cable to the 10/100 ETHERNET port.

CAUTION: Do NOT plug an Ethernet cable into the Room Sensor port, as the voltage may damage Ethernet equipment.

Note: Use T568B Category 5 or better cable, maximum 328 feet (100 meters). Default network settings for Ethernet models are: IP address 192.168.1.251, Subnet mask 255.255.255.0, Gateway 192.168.1.1.

Connecting an MS/TP Network

For TRF-5901AC-AFMS or TRF-9311AC-AFMS, connect the BACnet network to the gray BACnet MS/TP terminal block.

Note: Use 18 AWG shielded twisted pair cable (e.g., Belden #82760) with maximum capacitance of 51 pF/ft (0.3 m).

1. Connect the -A terminals in parallel with all other -A terminals on the network.
2. Connect the +B terminals in parallel with all other +B terminals on the network.
3. Connect the cable shields together at each device using a wire nut or the S terminal.
4. Connect the cable shield to earth ground at one end only.
5. If the controller is at either end of the network, turn the EOL (End-of-Line) switch to ON.

Note: Refer to Planning BACnet Networks (Application Note AN0404A) for network best practices.

Connecting Power

Connecting Power to the Controller

Connect a 24 VAC, Class-2 transformer to the black power terminal block:

1. Connect the neutral side of the transformer to the controller's common terminal (⊥).
2. Connect the AC phase side of the transformer to the controller's phase terminal (~).

Note: Connect only one controller per transformer using 12-24 AWG copper wire. Use shielded cables or conduit for RF emissions compliance.

Note: For DC power, refer to the KMC Conquest Controller Application Guide.

Connecting Power to the Inclinometer

1. Connect the red power wire to UO8 (TRF-5901AC[E]-AFMS) or UO10 (TRF-9311AC[E]-AFMS).
2. Connect the blue ground wire to GND/SC on the controller.

Connecting Power to the Pressure Transducer(s)

Note: Complete these steps only if using a TRF-5901AC(E)-AFMS controller. Use 22 AWG, shielded, twisted-pair wiring. Do not run device wires in the same conduit with inductive loads.

CAUTION: Ensure the circuit ground point is the same on all devices and the controller when grounding the secondary of an AC transformer or wiring multiple devices.

1. Connect the controller's phase terminal (~) to the transducer's PWR terminal.
2. Connect the controller's common terminal (⊥) to the COM terminal on the transducer.
3. If a second transducer is used for pressure assist, repeat steps 1 and 2 for that transducer.

Connecting Power to the Proportional Actuator

For wiring instructions for MEP-series actuators (MEP-4552, MEP-4952, MEP-7552) to power and for complete setup, refer to the specific model's installation guide available on the KMC Controls website.

Controller Power and Communication Status

Status LEDs on the TRF-5901AC(E)-AFMS and TRF-9311AC(E)-AFMS indicate power and network communication.

Note: If both READY and COMM LEDs are OFF, check power and cable connections.

• Green READY LED: Flashes about once per second after power-up/restart, indicating normal operation.
• Amber (BACnet MS/TP) COMM LED: Flickers during normal operation as the token is passed. Flashes about once per second if the network is not connected or communicating properly.
• Green ETHERNET LED: Stays ON when the controller is communicating with the network. OFF when not communicating.
• Amber ETHERNET LED: Flashes when communicating at 100BaseT. OFF when communicating at 10 Mbps.

Controller MS/TP Network Isolation Bulbs

The two network isolation bulbs serve three functions:

• Removing the bulb assembly (HPO-0055) isolates the controller from the network.
• If bulbs are ON, the network is improperly phased (ground potentials differ). Fix wiring.
• If voltage/current exceeds safe levels, bulbs blow, opening the circuit. Fix the problem and replace the bulb assembly.

Wiring Diagrams

Detailed wiring diagrams are provided for the TRUEFIT Airflow Measurement System models TRF-5901AC(E)-AFMS and TRF-9311AC(E)-AFMS, illustrating connections for the inclinometer, sensors, pressure transducers, and network communication.

Inclinometer Mounting: Mount to a horizontal damper blade (preferably outside air) with the cord parallel to the blade. Attach with two sheet metal screws and secure the cord to prevent damage or impede operation.

Supply Air Flow Measurement: Install enough differential pressure flow sensors (at least 2) in a location of laminar flow (approx. 6 straight duct widths down the duct). Ensure high-pressure ports face upstream and low ports face downstream. Connect all high ports in parallel to the controller's HIGH port, and similarly for low ports.

Notes:

• Controller settings must be initially set using an STE-0XX1 or STE-9XX1.
• Refer to AFMS Selection, Installation and Application Guides for additional details.
• Visit www.kmccontrols.com for accessories and further information.

Input/Output Objects/Connections

TRF-5901AC(E)-AFMS

TRF-9311AC(E)-AFMS

Configuring and Operating

For configuration and operation, refer to the documentation for each tool used. The table below outlines the capabilities of various configuration tools:

1 Ethernet (E) models can be configured via a web browser.
2 KMC Commander's AFMS module supports the standard AFMS application only.
3 Near Field Communication via smartphone/tablet with KMC Connect Lite app.

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Important Notices

The information in this document is for informational purposes only. The contents and product described are subject to change without notice.

KMC Controls, Inc. makes no representations or warranties regarding this document and shall not be liable for any damages arising from its use.

KMC logo is a registered trademark of KMC Controls, Inc. All rights reserved. KMC Connect Lite™ app is protected under U.S. Patent Number 10,006,654. Patents: https://www.kmccontrols.com/patents/

Contact Information:
TEL: 574.831.5250
FAX: 574.831.5252
EMAIL: info@kmccontrols.com