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BCU 560, BCU 565 · Edition 02.16
126
19 Legend
Ready for operation
Safety interlocks
Control element position check
LDS Safety limits (limits during start-up)
Gas valve
Air valve
Air/gas ratio control valve
Burner
P
Purge
Controlled air flow
Operating signal
Fault signal
Start-up signal (BCU)
menox
®
input
HT
Input for high temperature operation
PZ
Pressure switch for tightness control (TC)
PZH
Pressure switch for maximum pressure
PZL
Pressure switch for minimum pressure
PDZ
Differential pressure switch
P xx
Input signal depending on parameter xx
M
Actuator with butterfly valve
TC
Tightness test
p
u
/2
Half of the inlet pressure
p
u
Inlet pressure
p
d
Outlet pressure
V
p1
Test volume
GZL
Valve with proof of closure switch
Fan
Three-point step switch
Input/Output, safety circuit
I
N
Current consumption of sensor/contactor
t
L
Tightness control opening time
t
M
Measurement time during tightness test
t
P
Tightness control test period (= 2 x t
L
+ 2 x t
M
)
t
FS
Flame proving period
t
PN
Post-purge time
t
GV
Fan run-up time
t
E
Switch-on delay
t
SA
Safety time on start-up
t
VZ
Pre-ignition time
t
PV
Pre-purge time
t
RF
Controller enable signal delay time