OPEARATION & ARCHITECTURE BACKGROUND

• Powerline Background

Powerlines are a method of transmitting Ethernet data to & from multiple Ethernet devices, such as HelixNet User Stations, via a shared cable.  This is done by RF modulating the Ethernet RX/TX to a XLR cable connecting all HelixNet User Stations where the RF signal is converted again to Ethernet RX/TX.  
The modulated carriers high speed signals in the frequency range of 1.8-67.5MHz transversing the external atoms of the cable and emitting towards the shield that practically keeps the signal in the cable (hopefully you have a shield).
Due to the high frequency signals cable attenuation also becomes a big factor. The more attenuation the less data can be pushed through the cable. Cable capacitance, accumulated over cable length, increases attenuation.

Frequency carriers are automatically detected and manged by all devices on the Powerline which should be considered to be the equivalent of a “RF Space” in wireless communications such as FreeSpeakII.  Hence, it is important that the signals do not cross between disparate Powerlines and their physical isolation be maintained with shielding and/or physical separation. If crosstalk is experienced the HelixNet User Stations may not be connected to the optimal DPL Powerline Device or HMS Powerline port and therefor struggle with maintaining good connectivity to the system and/or audio. 

• HXII-DPL Powerline Device
  HXII-DPL is an Ethernet <-> Powerline bridge and power injector
  1 Powerline per device. Ability to add it to a system as-needed, where-needed.
  HelixNet User Stations connected via HXII-DPL are configured as if they were Network connected HelixNet User Stations,
  HXII-DPL has no firmware or user configuration. It simply passes Ethernet between a RJ45 to XLR connector.

• Powerline Cabling
  For best performance use standard 3 pin XLR cable

  • Continuously Shielded to maintain the modulated Ethernet signals inside the cable.
    Note: Take care with junction boxes, wiring terminals, rear of XLR bulkhead/panel connectors etc.

  • Low Capacitance for low attenuation at high frequencies for optimal data transmission.
    Note: Star Quad cable is notoriously high capacitance and should be avoided. AES cable is low capacitance.

  • Low Resistance for best power delivery along a long cable with low voltage drops at User Stations
    Note: Small gauge (/more copper) is always better! AES cable is often high gauge (/little copper)!  

Powerline cabling distribution is passive using regular “Y” cables and pass throughs as appropriate for the device and cabling
Powerlines can be wired in star, daisy chains or both.
Powerlines can be connected in a loop for redundancy.

• System & User Firmware prerequisites
  HelixNet User Stations must be running HelixNet v4.5 (inc in Arcadia v2.11) to operate with the HXII-DPL Powerline Device and will not connect or upgrade until at version 4.5 or higher.
  HelixNet User Stations should upgrade to v4.5 via Ethernet or HMS Powerline Ports before use with HXII-DPL Powerline Device
  HelixNet User Stations connected via HXII-DPL Powerline Device will not downgrade below v4.5
  Legacy HBP-2X beltpack must be upgraded to v4.5 via HMS Powerline Port before use with HXII-DPL and Arcadia.  USB booth procedure exists for emergencies. It is important to train those who will be using the legacy beltpack on how to best manage their inventories and USB backup plans to avoid the disappointment of accidental version mismatch.

• HelixNet User Stations Capacity Limits.
  HXII-DPL is specified for
  * 7 Beltpacks on the line or
  * 2 Remote or Speaker Stations powered of the line or
  * 7 User Stations of any type if Remote & Speaker Stations are locally powered

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PERFORMANCE TESTING
start below with one HXII-DPL powerline device and then add HXII-DPL units and observe: 

• Powerline User Station Capacity
  -> Test as many wiring and loading scenarios as you can! Make notes of what was tested, audio performance & powerline statistics (rx/tx bandwidth, errors, collisions etc)

• Powerline cable length
  -> test as is practical and make notes of lengths vs cable type vs performance in Arcadia CCM or User Station Front panel diagnostics (data, error, collision rates)

• User Station
  -> add and subtract from the line up to capacity without system interruptions 

• Audio performance
  -> check perceived latency, audible interruptions, or artifacts for all above conditions

• Powerline power overload limiter
  -> test the overload protection, as appropriate, protecting to shorts and automatic recovery

• System startup and User Station connection reliability.
  -> Observe devices (system host, network, Powerline Device, User Station) get powered and connected reliably (passing audio and call signals!) in any order within a reasonable time (2-3min max depending on the network performance). Take Support Info from the Arcadia/HMS if any issues are experienced and forward to investigation.

• Arcadia CCM Status Screen
  -> Observe HXII-DPL Powerline Device presence in the system, HelixNet User Station connections via Powerline, Powerline statistics

Once you have tried with 1 HXII-DPL powerline device, try with more units, and run the same tests.

• Powerline crosstalk can manifest itself with low data rates (9 or 0Mb ) or high error rates causing unstable connections and/or stuttering audio or the data rate 9 or 0Mb.
  In the HelixNet User Station Front Panel Menu you can see the MAC address of the Powerline device it is connected to in the user stations front panel diagnostics menu.
  
  

  Open

  

  
  If Powerline crosstalk is experienced at startup, then it is recommended to wait a few minutes as the User Station will attempt to connect to the best Powerline Device (this mechanism does not work between HXII-DPL Powerline Device and HMS Powerline Ports, so it is recommended to keep those further apart!).
  Shielding integrity of cables between different powerlines should then be verified and physical separation added between the lines to observe change.

  Note: HXII-DPL has higher sensitivity than HMS Powerline Ports. This is good for longer cable distances. Crosstalk behaviour could be different, and we would like to learn as much about it with real world tests as is possible.