A communication cable is used to connect the Cloud Connect Advanced (CCA), Cloud Connect (CC) or the Maximizer Management Unit (MMU) with either a TAP (Tigo Access Point) or a Gateway (GW). For purposes of this discussion, the terms CCA and TAP will be used.

1. Use a twisted pair for the A and B wires.
2. Use 1 or 3 twisted pairs combined for power.

The following requirements and recommendations are discussed in this article:

• TAP Cable Requirements
• Recommended Cables
• Distance Guidelines
• Use of Ethernet Cables
• TAP to Panel Installation Tips

Note 1: The TAP and Gateway serve the same function. TAP is the latest version of Tigo's communication gateway, and Gateway is the orignal version name. To identify which device you are using, see TAP vs Gateway. Gateways do use a different wire connection method

NOTE 2: There are 2 methods of connecting the wires to the TAP:

1. Via the IDC punch-down terminals.
2. Screw type connector.

Choose one way, and apply it throughout the whole plant/site.

Communication Cable Requirements

Industrial RS-485 cables are manufactured as both Shielded and Unshieded types. They are always made with the wires twisted around each other in 2-wire pairs, The cables pairs have a impedance of 120 Ohms. They are typically made using wire of either 18, 22 or 24 American Wire Guage (AWG).

For use with TAP the cable must have these features:

• 2 twisted pairs.
• Unshielded (UTP) or shielded (STP) - either is normally acceptable but STP cable is recommend for use when it is located nearby to a device such as an electrical motor that can create strong Electro-Magnetic fields includinig radio transmitters.
• Minimum wire size of 22 AWG (0.33 mm²).
• Maximum cable outside diameter (OD) of 0.35 inches (9 mm) so it will fit in the cable gland.
• If not in a protective conduit, use outdoor-rated (UV resistant) sheathed cable.
• Also, check on possible local jurisdictional cable requirements.

It is typically easier to find cables meeting these requirements by searching for un-shielded (UTP) cables, which are also less expensive.

For guidance on connecting the cables between the CCA and TAP see the Interactive Installation and Safety Manual and Opening and Closing TAP Cover.

Communication Cables for installation in a conduit or tray with 600 VDC or less wiring

When running the communication cable in the same conduit as a PV wire some cables that can be used are due to their 600 VDC insulation rating:

• Omni Cable's 600V 18AWG 4-Conductor Tray Cable, P/N A21804
• Omni Cable's 600V 18AWG 2-Pair Tray Cable, P/N L21802

These, and other 600 VDC rated sheathed communication cables, eliminate the need for the installation of a separate conduit for the communication cable in systems where the string voltage will never exceed 600 VDC.

Maximum Distance Recommendations

This table provides the maximum distance for the cable, based on the...

1. AWG size of the wires used in the cable.
2. Number of TAPs connected to the cable.
3. Distance from the CCA to the furthest away TAP which is at the end of the daisy-chain of TAPS.

Note: The values are in feet with meters in parentheses.

Note: Each column is for the number of TAPS connected.

Usage of Ethernet Cables

Systems may be able to use Ethernet cable. If not protected in a conduit, outdoor-rated cable should be used. If installed next to PV wiring ensure the Ethernet cable sheath voltage rating is sufficient. Most Ethernet cable is rated to a maximum of 300 VDC.

NOTE: For commercial systems, using Ethernet cable is not recommend due to the combinations of longer cable length and the number of TAPS, which may exceed the recommendations in the above cable length table.

Using 2 or more TAPs, and/or for longer distance:

Use 3 pairs for power, 1 wire from each pair combined for "+" (positive), and the other wire from each pair combined for "-" (negative)

NOTE: Only use the screw-type connector, not the punch-down IDC terminals.

Using the Insulation Displacement Connector (IDC) terminals:

This method may be used for up to 2 TAPs.

• The IDC punch-down terminals are for use with wire sizes of 20 to 32 AWG wire. Do not attempt to use them with anything larger than 20 AWG wire.
• Use the main terminal blocks for a larger AWG wire such as 18 AWG or 16 AWG.

Ethernet Installation Steps:

1 - First, remove 3 cm (1-1/4") of the sheathing.

NOTE: Do not nick or damage the wires insulation. If damage is incurred, cut the cable off and start again.

2 - open the TAP and identify the terminal block that will receive the connections.

See the Red Arrow. It does not have a resistor installed between A and B terminals.

3 - Remove the screw type terminal connector:

Using a flat bladed tool, gently rotate it clockwise and counter clockwise to loosen it.

4 - Feed the cable through the cable gland:

This can be done before removing the sheathing.

5 - Punch Down the Wires

Using a IDC Punch Down tool, or a small flat bladed screwdriver, push the leads into the quick connector terminals.

NOTE: Push only 1 wire into each terminal.

NOTE: See below picture for how to position a screwdriver properly to insert the wire into a terminal.

NOTE: Only use the same twisted wire pair for the A/B connectons, and also for the + and - Power connections. In the below picture BLUE is connected to B, and White with Blue stripe is connected to A.

6 - Connect Power Wires

Push the wires of a single pair of wires into the "+" and "-" terminals.

7 - Tighten the gland

Ensure it is firmly tightened to prevent water entry. Also the Glands should be closer to the earth than the far side to allow water to drip away, and not in to, the housing.

8 - Close the TAP. Click this link to see how to correctly Close the TAP.

Installation Tips

• TAP is designed to be installed under a panel, not out in direct sunlight.
• A resistor is pre-installed on the right-hand side terminals connected to the A and B terminals, which are the RS-485 data signals.
• For each TAP connected in the middle of a daisy-chain of units, the resistor needs to be removed.
• The last TAP in the chain must have the resistor installed.

  • The resistor is to be connected to the A and B terminals, as shown on the right hand side terminals in this picture:

  • 

• Tigo recommends installing the TAP on the frame of a panel, not in an attic or other radio signal decreasing barrier. The signal radiates horizontally to the sides, not towards the sky or ground.

• Locate it near the center panel of the array whenever possible.

•  

  The TAP connects to the panel frame using the mounting bracket, as can be seen in the picture above. If desired, the brackets holes can be used with screws and nuts to attach it to a panel racking system.

• When closing the TAP, make sure the TAP closes properly, and tighten the cable gland.

  • The TAP has a side that must face towards the panel and that means the labels will be facing outward towards the roof or ground.

  • The correct installation is shown in the above picture. Note that the labels are visible.

• At the data-logger, run a Gateway Test.
  • You can do this by using the MMU and CC control panel.
  • For CCA use the Tigo SMART Application installed on your phone or tablet.