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TRACO 5V PSU Failure — Ethernet Hub Has No Power / Bolt Nodes Not Connecting

CONFIRMED BOLT / MILO

Summary

Inside the Bolt (and some Milo) bases there is a TRACO switching power supply that provides 5V to the internal BlackBox ethernet hub. When this TRACO unit fails (no output voltage), the hub loses power, and Flair loses its network connections to the robot's control nodes — the rig appears to connect but one or more nodes are unreachable. The fix is to replace the TRACO PSU. A temporary workaround is to supply 5V externally (USB battery pack or phone charger) directly to the hub. This has been seen in at least two separate incidents: July 2020 and January 2026.

Symptoms

  • Bolt/Milo nodes not connecting — "Node A not connected" or similar errors in Flair
  • Direct connection from PC to the rig's external RJ45 port works, but internal nodes fail
  • The internal BlackBox hub appears to have no power (no LEDs on the unit)
  • Supplying 5V directly to the hub (USB battery pack) restores network connectivity immediately
  • Hardware has been running for extended periods without issues before failure

Cause

The TRACO switching PSU inside the rig base (typically rated 5V/1–2A) has failed — either from extended runtime, heat, or age. These units are compact DIN-rail or PCB-mount switching supplies; they can fail with no warning and no visual indication (no blown fuse, no burnt smell).

Power jack displacement

Timothy Heys Cerchio (2026): "Sometimes the Network Hub in the Bolt base loses power because the tiny power jack gets displaced by movement/vibration." — Before assuming the TRACO has failed outright, also check that the hub's power jack is firmly seated. Transport vibration can dislodge it.

Fix

[CONFIRMED] Replace the TRACO 5V PSU

  1. Power down the rig completely
  2. Open the Bolt base access panel to locate the internal TRACO switching supply
  3. Note the TRACO part number and voltage/current rating
  4. Order a direct replacement (TRACO Power or equivalent 5V switching PSU of the same form factor)
  5. Swap the unit and reconnect
  6. Power up and verify hub LEDs are active and all nodes connect

[TEMPORARY] Supply 5V externally to the hub

If the TRACO replacement is not immediately available:

  1. Identify the 5V input to the BlackBox hub (typically a barrel jack or USB port on the hub)
  2. Connect a USB battery pack or USB phone charger (5V, 1A minimum) to the hub's power input
  3. Route the external cable out of the base safely (do not pinch cables in the panel)
  4. Verify hub LEDs are active and nodes connect
  5. Order the TRACO replacement as soon as possible — this is a temporary measure only

Eko (2020): "I try connect blackbox hub with usb battery and work again, so I have to change traco switching PS."

Nitin (2026): "I seem to have lost power coming out from the traco unit supplying 5V. Using my phone charger as a back up for now to give 5v to the hub."

[OPTION] Replace BlackBox hub with a better switch

If the hub itself is also aging (the BlackBox units have a history of reliability issues), consider replacing it at the same time with a modern small managed switch (TP-Link or Netgear 8-port). Dan Gottesman (2026): "The Black Box ethernet switch that shipped with all of our rigs proved to be troublesome enough for us to replace them all." A new switch is easier to see status on (the BlackBox's status LEDs are on top and very small).

confidence_score: 0.88

WhatsApp Excerpts

[17/7/2020, 5:29:23 am] ~ Eko: No power from Traco switching ps

[17/7/2020, 5:32:40 am] ~ Eko: I try connect blackbox hub with usb battery and work again, so I have to change traco switching PS

[17/7/2020, 6:53:51 pm] Gordon Eschke: Are you saying the TRACO 5V PSU is not working?

[17/7/2020, 6:54:00 pm] ~ Eko: Yes Gordon

[17/7/2020, 6:54:00 pm] ~ Eko: No output

[22/1/2026, 4:29:44 am] ~ Luke Campbell: I've had the hub on the fail station side to forward arp messages on properly - we just replaced it, we were losing our ultibox but it was the flair computer hub that actually caused the issue. So yeah work through your networking

[22/1/2026, 5:39:41 am] ~ Dan Gottesman: I've been using small (8 or 16 port) switches from TP-Link and/or Netgear, which have been quite reliable.

[22/1/2026, 5:52:42 am] ~ Nitin: I seem to have lost power coming out from the traco unit supplying 5V. Using my phone charger as a back up for now to give 5v to the hub.