InteliMains
NT
, SW version 3.0  
InteliMains-NT-BTB-3.0-Reference Guide.pdf, ©ComAp – June 2013   
7.6  Controller Redundancy 
Redundant system is a general term for applications where there are two controllers at each gen-set. 
One is the main controller, which controls the gen-set in normal conditions, the other is the redundant 
controller, which takes over the control when the main controller fails. Both controllers have identical 
firmware  and  most  of  the  configuration  and  setpoints.  Only  several  things  need  to  be 
adjusted/configured differently because of the rendundancy function itself. 
CAUTION!  
If  there  are  shared  binary  or  analog  outputs  used  on  InteliMains  (e.g.  for  system  start/stop),  it  is 
necessary to prepare the configuration in the way so each controller uses binary or analog output set 
with different address. Configuration in gen-set controllers then needs to be altered so it can receive 
signals from both InteliMains controller (e.g. using built-in PLC functions).  
7.6.1  Redundant systems using binary signals 
It is not possible to use this redundancy system since correct function of InteliMains depends on CAN 
bus communication and thus CAN redundancy should be always used. 
7.6.2  Redundant systems using CAN bus 
This system uses the CAN bus for detection whether the main controller is operational or not. If the 
redundant controller has not received two consequent messages from the main one (~100ms) it will 
take over the system control - it activates the binary output CTRLHBEAT FD, which has to be wired in 
such a way, that it disconnects the dead main controller from the  control, connects the redundancy 
controller instead and activates it by deactivation of the binary input EMERG. MANUAL. 
As there can be up to 16 pairs of controllers at the CAN bus it is necessary to select  which main 
controller (address) belongs to which redundant one. The setpoint ProcessControl:Watched Contr is 
used  for  this  purpose.  It  must  be  adjusted  to  address  of  the  respective  main  controller  in  each 
redundant controller and it must be adjusted to 0 in each main controller. 
CAUTION!  
Correct  wiring  of  all  inputs  and  outputs  that  should  be  used  both  by  the  main  and  the  redundant 
controller needs to be done. Please refer to the corresponding chapter for wiring of binary inputs and 
outputs. 
Do not use Shared Binary Inputs/Outputs for CTRLHBEAT FD -> EMERG.MANUAL connection since the 
failed controller may not interpret it correctly! 
VPIO
VPI
VPO
CtrlHBeat FD
Emerg. manual
CAN
LOG BOUT
LOG BIN
Watched contr = X
Setpoint
Emerg. manual
LOG BIN
CAN
BOUT
BIN
LOG BIN
MAIN CONTROLLER
REDUNDANT CONTROLLER
Contr. Address = X
Setpoint
 
Figure: Example of redundancy function