Troubleshooting CellMon Network for faults - WatchMon4

This troubleshooting page will help you to:

  • Start the Network Tester
  • Locate the cell monitor network fault
  • Testing the WatchMon RX / TX and CMU connect cable
  • Inspecting cell monitor cables for problems and how to fix

    Starting the Network Tester:

    The Network Test will constantly transmit a message to CellMons to keep both Red and Green LEDs turned ON.

    The LEDs will turn (ON) from the first CellMon in the chain, up to the break in the network making troubleshooting the problem very visual and easy.

    Step 1 - Click on "Menu" then click on "Hardware"



    Step 2 - Click on "CellMon" tab


    Step 3 - Click on "Network Tester"

    Step 4 - Before starting the Network Tester, make sure the number of cells you are testing is matching the number of CellMons connected to the WatchMon supervisor. If you have 14 cell monitors the "Last Cell ID" and "GroupAck" should be showing "14" as per example below:

    Note: If the number is wrong, go back to Wizard setup and set the correct number of CellMons in your system.

    Step 5 - When you click on the "Start" button, the system will begin to interrogate the CellMon modules to turn both Red and Green LEDs "ON". The test won't stop until you manually click on "Stop". This enables you to take time finding exactly where the network stops and also time to fix the problem.  

    Note in the picture below GroupAck is showing "0" on the RX box meaning that there is a network problem.

    Procedures to locate the cell monitor network fault:

    The transmission data starts at WatchMon4 supervisor CMU port. There is a Red TX LED on WatchMon4 indicating that it is transmitting / sending the message to the first CellMon (Red LED should be flashing).

    Below is the CMU cable "connection box" where you connect the CellMon blue/yellow communication cables. WatchMon4 users should have one that comes with the Starter Kit.

    The Network Tester sends data starting from the 4 pin small white connector sending the message to the very first CellMon. If the network is complete without interruptions, the message should pass through all cell monitors and return back to the 2 pin small white connector. 

    Step 1 - Trace through each subsequent CellMon. Observe that each CellMon has both the Green and Red LEDs are ON.

    The message on the CellMon goes inbound to the 2pin and then outbound from the 4 pin connector of the following CellMons and back to the WatchMon.

    The Green RX LED on the WatchMon4 supervisor (below) indicates if the daisy chain network is complete and perfectly working without any interruptions.

    Make sure to visually verify the cell monitor cables/connectors, it could be something as simple as an unplugged / not properly connected cable.

    Example below: battery pack in the dark with NetworkTest running all LED light (Comms OK).

    Battery pack in the dark with NetworkTest running, break at cell #5 (see cable unplugged). All the following cell monitor LEDs turned OFF.

    If you checked all connections, everything looks right but the network still with a fault, try swapping cables and CellMons, this is the best way to detect exactly where the fault is. Also inspect the red/black wires connected to the battery terminals. It could be either a damaged cable or damaged CellMon.

    When the faulty connection is located and fixed, the "GroupAck" will detect CellMons and display the correct number also displaying a green "SUCCESS" message:

    Testing the WatchMon RX / TX and CMU connect cable:

    A very simple and easy way to test if your WatchMon and CMU connect cable are working, connect a loop cable and inspect the LEDs on the WatchMon.

    You should see both Red and Green LEDs turned ON.

    Green LED ON means the daisy chain is working, this confirms that your WatchMon is sending and receiving data through the CMU connect cable. If you disconnect one of cables breaking the chain, the Green LED will turn OFF.

    Inspecting cell monitor cables for problems and how to fix:

    It is also a good idea to swap cables and cell monitors around, this also helps finding exactly what cable is causing the problem.

    Inspect cables for any issues with the connector, make sure the color sequence is matching this example below:

    Note: some cell monitor cables such as BlockMon won't have the black wire

    Replace the cable if there are any issues, these little connectors aren't easy to repair. We recently started including a spare cable to all orders just in case.

    Inspect the Red and Black ring terminals. If the cell monitor is not connected to the battery terminals properly it won't work therefore stopping/breaking the daisy chain network communication. 

    Unfortunately we had some cases where the Red or Black wire was not soldered/crimped properly to the ring terminal. Here is a VIDEO we prepared showing a simple way to inspect and how to quickly fix soldering or crimping avoiding any delays making sure you get your system up and running as soon as possible.

    Next Steps:

    Synchronising the Cell monitors using Device Sync

    Testing Cell monitors balancing resistors with Bypass Tester 


    How to fix cell monitor cables

    How to connect the Cell monitors to WatchMon4 supervisor 

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