Tigo Access Point (TAP) Communication Cable Types and Installation

Contents: 

1. TAP Communication Cable Requirements
2. Recommended Cable Types
3. Maximum Cable Length Recommendations
4. Using Ethernet Cables (Cat 5 / Cat 6)
5. How to Wire the TAP

Introduction

This article covers the cable requirements and wiring methods for connecting a Tigo Access Point (TAP) to a Cloud Connect Advanced (CCA), including:

• Communication cable requirements
• RS-485 and CAT5/CAT6 cable selection
• Maximum cable lengths
• Cable routing requirements
• CCA-to-TAP wiring
• Multiple TAP wiring and termination

These requirements also apply to legacy systems using the Tigo Gateway or MMU. See TAP vs. Gateway for additional information.

For complete TAP installation instructions, refer to the TAP Installation Manual available on the Tigo Downloads page.

TAP to CCA Cable Requirements

The cable used to connect a TAP to the CCA must have these features:

• 4 conductors to connect A | B | + | - from CCA to TAP or from one TAP to the other
• At least 1 twisted-pair wire (for A and B connections)
• Cable size: 22 AWG to 18 AWG (0.34 to 1 mm²)
• Max TAP cable gland outside diameter: 11/32 inches (0.346"), 9mm 

Always check with your Authority Having Jurisdiction (AHJ) for local wiring requirements, and check the product datasheet for exact and current specifications: TAP Datasheet

Running the TAP cable in the same conduit as the DC homeruns

If the TAP to CCA cable will be run in the same conduit as the inverter DC homeruns, then the TAP cable must be rated to either 600V or 1000V, depending on the application (refer to NEC 300.3(C)). Using lower-rated cable could introduce interference onto the TAP cable and affect normal operation.

Cable selection depends on the distance from the CCA to the farthest TAP and the number of TAPs connected to the CCA.

RS-485 Cable

Tigo recommends shielded RS-485 communication cable for:

• Commercial installations
• Systems with more than 2 TAPs per CCA
• Cable runs greater than 100 ft (30 m) from the CCA to the farthest TAP

Commercial PV systems may have higher levels of electromagnetic and radio-frequency interference (EMI/RFI). Shielded RS-485 cable provides greater protection against communication interference and potential data errors.

IMPORTANT: For commercial installations, use shielded RS-485 rated communication cable for CCA-to-TAP wiring.

The cable must meet the TAP communication cable requirements specified in this article, including conductor size, number of conductors, and maximum cable diameter.

Select a cable with the appropriate environmental and voltage rating for the installation. If the TAP communication cable is installed in the same raceway as PV DC conductors, the cable must have a voltage rating that meets applicable electrical codes.

Ethernet Cable (CAT5/CAT6)

CAT5 or CAT6 cable may be used for smaller systems when:

• No more than 2 TAPs are connected to the CCA, and
• The distance from the CCA to the farthest TAP is less than 100 ft (30 m)

Ethernet cable must be wired correctly for TAP communication. Before installation, see Using Ethernet Cables (CAT5/CAT6) below for conductor pairing and wiring requirements.

Maximum Cable Lengths are based on the number of TAPs/CCA:

• The length of a cable, along with its wire size, determines its resistance.
• Longer cables have more resistance.
• Do not use Ethernet cable for commercial applications.

The following table provides the maximum length recommendations per cable type and number of TAPs.

1. Wire sizes are listed in American Wire Gauge (AWG) and Millimeters (mm).
2. Wire Lengths are listed in Feet (ft) and Meters (m). 

Cable Routing Requirements

TAP communication cable may be installed in the same conduit or raceway as PV DC conductors when permitted by applicable electrical codes.

IMPORTANT: When installed with PV DC conductors, the TAP communication cable must have a voltage rating suitable for the application. Standard RS-485 or Ethernet communication cable may meet the TAP communication requirements but may not have the required voltage rating for installation with PV DC conductors.

Connecting the TAP to the CCA (Residential)

1.  A and B signals:  Use 2-wire from the same pair.
2. To minimize voltage drop, extra pairs can be combined for the power signals + and -.
   (This can be helpful for distances over 100 feet, or on systems with 2 or more TAPs.)
3. The picture uses the pair color code of Blue and White/Blue for A and B.

Conductor Installation

STEP 1

1. Open the TAP by pressing the lid release at the bottom.
   Opening and Closing the TAP.
    
2. Use the left side terminal for CCA to TAP connection.

STEP 2

Run the cable through the left-side cable gland on the bottom of the TAP

1. Strip 1.25 inches of outer jacket from the cable 
2. Strip 3/8 of an inch of each wire

STEP 3

Reconfigure the conductor pairs as shown below before connecting them to the TAP:

• Use two conductors from the same twisted pair for the A and B communication terminals.
• Combine the remaining conductors as shown for the + and – power connections.
• Keep the A and B conductors twisted together as close to the TAP terminal as practical.

Install ferrules on the prepared conductors when recommended.

Follow the conductor assignments shown in the diagram below.

STEP 4

1. Loosen the screws until there is space for the wire(s).
2. Insert the wires into the connector and tighten them until a firm tug does not remove them, but NOT so tight as to cut/break the wire.
3. Press the connector back onto the pins until it contacts the printed circuit board.

IMPORTANT!
Termination Resistor Considerations

A termination resistor is factory-installed across the A and B terminals on the right side of the TAP.

When daisy-chaining multiple TAPs, remove the resistor from each TAP except the last TAP in the chain. The termination resistor must remain installed across A and B on the last TAP.

Incorrect placement of the termination resistor |is a common cause of TAP communication issues and service calls.

Multiple TAP Wiring

Terminating resistors removed on all but last TAP

STEP 5

1. Firmly tighten the cable gland to prevent water entry.
2. Close the TAP cover

Additional Resources

Need design assistance?
For assistance with an upcoming project, use the Tigo Green Glove service.

Help Center Articles
TAP Placement and Layout Requirements
What are the CCA and TAP power requirements?
TAP Basics - What is a TAP?
Commissioning the Cloud Connect Advanced (CCA) - Getting Started
 

Video: Top 5 Installation Tips for the CCA and TAP