Wiring the adapter to a communications network - PENN Controls - ADPT-MR5-RS485 - Electronic Refrigeration, Defrost, and Multi-Purpose Controller - ADPT‐RS285‐MR5 Communications Adapter

ADPT-MR5-RS485 Network Communications Adapter Installation Guide

PENN Controls
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ADPT‐RS285‐MR5 Communications Adapter
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Installation Guide
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  1. Press the terminal tab with a flat-head screwdriver, and insert the end of the wire into the opening, as shown in the following figure.
    Figure 1. Connecting wires to the terminal block
    Table 1. Adapter field wiring connections
    Terminal label callout Description Wire size
    1 Terminal open and close tabs.
    SHD The shield connection (SHD) is a dead-end or blank terminal that you use to connect all of the network cable shield drains. 0.14 mm2 to 0.34 mm2 (26 AWG to 22 AWG) stranded wires and twisted-leads cable
    REF RS485 BACnet signal common or reference
    - Use the RS485 communications terminal block to create a network connection to RS485 MS/TP BACnet networks, including Johnson Controls Verasys networks.
  2. Connect the terminal block to the other network devices in a daisy-chain configuration using 3-wire twisted, shielded cable. Use the SHD terminal to splice the cable shields along the daisy-chain bus.
    Note: Splice and isolate the cable shield drains at all of the devices on the network trunk. Connect the cable shield to the ground at one point along the daisy chain only. It is standard to connect the cable shield to the ground at the master device.
    Figure 2. Adapters in a daisy-chain configuration
    Table 2. Adapters in a daisy-chain configuration
    Callout Description
    1 End-of-line (EOL) terminating device on the network trunk
    2 Daisy-chained devices on the network trunk
    3 Isolated shield connection terminal
    4 To the next device on the network trunk
    5 220 ohm EOL resistor