ComAp IG-NT Reference Manual page 15

ΣPg*
Sum of Nominal power of all gen-sets on the bus apart of the one, which is going to be
Nom
stopped.
ΣPg
Sum of Actual power of all gen-sets on the bus = system load.
Act
N :
OTE
System starting sequences may be very different due to their complexity (i.e. gensets which do not take part
in power management, various nominal powers etc.). Each system should be considered individually.
Optional functions in absolute or relative Power management are:
- Running hours balancing (equalization) – in absolute or relative pwr mgmnt
- Load demand (different size) engines swap – in absolute pwr mgmnt only
- Power management of two or more gen-set groups (bus tie support) – in absolute or relative
pwr mgmnt
Running hours equalization (RHE)
The gen-sets priorities are automatically swapped to balance engine running hours. Up to 32 controllers are
supported.
Activation: Pwr management:#PriorAutoSwap = RUN HOURS EQU
Important setpoints: RunHoursBase, #RunHrsMaxDiff, Priority ctrl, Control group
Basic settings:
Contr. Addr = 4
Pwr management:
#PriorAutoSwap = RUN HOURS EQU
Priority ctrl = MASTER
#RunHrsMaxDiff = 10h
Control group = COMMON
E :
XAMPLE
In this example the system is shown in previous figure. InteliMains assumes the role of master in priority
swapping and swappes priority of the engines based on their running hours.
Gen-set 1 running hours = 250 -> running hours considered in RHE = 150 (250-RunHoursBase)
Gen-set 2 running hours = 450 -> running hours considered in RHE = 250 (450-RunHoursBase)
Gen-set 3 running hours = 750 -> running hours considered in RHE = 450 (750-RunHoursBase)
All the engines have the same nominal power which is 700 kW. Originally priority of gen-sets was G1 = 3, G2
= 2, G3 = 1. Load demand in this example is constant and it is 500 kW (so only one engine is running at any
time).
InteliMains will change priority of gen-set 1 to 1 because it has the lowest considered running hours and gen-
set 1 will run for 210 hours.
After 210 hours, situation will change. Gen-set 2 will
now have the lowest considered running hours
(Gen-set 1 = 460, Gen-set 2 = 450, Gen-set 3 =
750). Gen-set 2 will now have priority 1 and it will run
for 20 hours. Then Gen-set 1 will run again for 20
hours. This will continue until both engines will have
running hours 770. Then the third engine will run. At that point engines will be swapping with period of 20
hours (2 x Pwr management:#RunHrsMaxDiff).
Inteli NT MINT, SW Version 3.0, ©ComAp –May 2013
IGS-NT-MINT-3.0 Reference Guide.PDF
InteliMains
G1
CAN
Basic settings: Basic settings:
Contr. Addr = 1 Contr. Addr = 2
Pwr management: Pwr management:
#PriorAutoSwap = RUN HOURS EQU #PriorAutoSwap = RUN HOURS EQU
Priority ctrl = SLAVE Priority ctrl = SLAVE
RunHoursBase = 100h RunHoursBase = 200h
#RunHrsMaxDiff = 10h #RunHrsMaxDiff = 10h
Control group = COMMON Control group = COMMON
Figure: Running Hours Equalization example
G2
Basic settings:
Contr. Addr = 3
Pwr management:
#PriorAutoSwap = RUN HOURS EQU
Priority ctrl = SLAVE
RunHoursBase = 300h
#RunHrsMaxDiff = 10h
Control group = COMMON
Second lowest considered running hours –
Current lowest considered running hours +
#RunHrsMaxDiff
450 – 250 + 10 = 210 hours
G3
15