Communication Failure The Modbus or Peer-To-Peer network has failed. When the Modbus network fails the following control mode changes are taken automatically:
Selected Modes Resulting Control Mode Modbus Mod Outlet Sensor and Local Setpoint Modbus Mod & Remote Sensor Remote Sensor and Local Setpoint Modbus SP Outlet Sensor and Local Setpoint Modbus SP & Remote Sensor Remote Sensor and Local Setpoint
After a Modus communication failure, the ‘Comm Failure’ alarm is not cleared until communication is restored and successfully writes to both the Remote On / Off Modbus Command (00004) and Remote Firing Rate or Remote Setpoint (40006) points have been completed, power is cycled or the protocol parameter is changed to Peer-To-Peer and then back to Modbus.
When a Peer-To-Peer network has failed the boilers begin operation as stand alone boilers using the selected parameters.
After a Peer-To-Peer communication failure the ‘Comm Failure’ alarm is not cleared until communication is restored and the boiler rejoins a network with at least one other boiler, power is cycled or the protocol parameter is changed to Modbus and then back to Peer-To-Peer.
Confirm each boiler has a unique address Check Wiring and Remote System
