This should only be carried out by advanced users. Setting up the master and satellite system requires some level of intricate technical skills and might need a level of support to accomplish. We do not recommend this on standard systems. This is recommended for significantly large systems (+200kWh), where you need more than 200 cells to be monitored, and wishing to break it up into separete parallel strings.
¶ How to Wire Up and Configure the CANbus Network as Satellites
Guide on how to configure the WatchMonCORE in using CANbus to communicate to the other WatchMon supervisors as satellites.
CANbus is a twisted pair of wiring used to connect the devices wired from the WatchMonCORE (WMC) to the first WMC, then onto the second WMC and so on, to form a chain.
The last WMC in the chain requires a 120 Ohm resister between CAN high and CAN low to indicate one end of the chain. The other end of the chain could be the WatchMonCORE (WMC) if there is no CAN link to an Inverter / Charger present or the Inverter / Charger itself.
If using an Inverter / Charger, this is normally inbuilt into the device. Where the WatchMonCORE (WMC) is one end of the chain, it too requires a 120 Ohm resister between CAN high and CAN low. It is common to adopt the typical CAT5 or CAT6 Ethernet network cable and adopt 1 pair.
¶ Uniquely Identifying the Devices for CANbus
The Hardware — CellMon page and Hardware — Integration page needs to be set up.
¶ Hardware Setup — CellMon Screen
The following should be configured within the Master Supervisor (i.e. WMC) as follows:
| Has Satellite: | On | Enabled to specify the entire range of satellites |
| First Cell ID: | 1 | Typically the lowest cell voltage in series |
| Last Cell ID: | 14 | Number of cells in series monitored by the local supervisor |
| Entire Range First: | 1 | Identical to the first cell |
| Entire Range Last: | 28 | Last number in the entire range of cells (typically the total number of cells monitored) |
| Dif Nominal: | On | Enable for multiple parallel strings, but off for high voltage systems in series |
| Nominal Series: | 14 | Outline the typical number when more than one parallel string |
On the WMC satellite, it should be configured as follows:
| Has Satellite: | Off | |
| First Cell ID: | 15 | The next number in the sequence (i.e. if after the WMC supervisor which has 1-14, it would be 15) |
| Last Cell ID: | 28 | The incremental number above the first ID for the number of cells monitored (i.e. if the first is 15 for 14 cells will be 28) |
| Entire Range First: | N/A | Calculated |
| Entire Range Last: | N/A | Calculated |
| Dif Nominal: | Off | |
| Nominal Series: | N/A | Calculated |
¶ Hardware Setup — Integration Screens
On the Master Supervisor (i.e. WMC) the following should be configured:
- Protocol: Project Coconut (or choose from other current integrations) for solar inverters (or Native2 for EV projects)
- The base address is 0x500. If multiple BMS supervisors exist on the same CANbus network, the addresses must be different and not overlap.
- The group address is 0x520. This is the same for all devices that are part of the same BMS so that both the master and satellites can see each other.
- The remote address is 0x0 and only relevant to communicate with a specific charger if a function of that CANbus profile.
On the WMC satellite, it should be configured as follows:
- Protocol: MultiMon Satellite or Aggregate Satellite (or Reserved 37 for faster updates)
- The base address is 0x540. If there are multiple each needs to be different (typically in increasing ranges of 0x20) and must not overlap (0x560, 0x580, etc).
- The group address is 0x520. This is the same for all devices that are part of the same BMS supervisor.
- The remote address is 0x0 — not relevant for satellites
