BCU 460, BCU 465 · Edition 11.19
83
Parameters
11 .5 .3 Safety time 1 t
SA1
Parameter A094
During safety time 1 t
SA1
, the flame (pilot flame) is ig-
nited. It can be set to between 2 and 15 s.
t
SA1
t
Z
88
02
03
ϑ
t
L1
V1
V2
V3
00
04
t
FS1
1
35
L
51
22
60
61
62
96
82
Safety time 1 starts with the application of the
ϑ
sig-
nal (terminal 1). The valves open at the start of safety
time 1. The fuel supply to burner 1 is released so that
a flame can form. If no flame is detected at the end of
safety time 1, the valves are closed again. Depending
on parameter A007 (Burner 1 start-up attempts), the
BCU reacts either with an immediate safety shut-down
with fault lock-out (A007 = 1) or with one or two ad-
ditional start-up attempts (A007 = 2 or 3). The BCU will
complete a maximum of three start-up attempts.
Safety time 1 must be determined on the basis of cur-
rent national standards and regulations . The burner
application and the burner capacity are the main cri-
teria for this .
If the
ϑ
signal (terminal 1) drops out during safety
time 1, the valves will not be switched off until the end
of safety time 1.
11 .5 .4 Flame proving period 1 t
FS1
Parameter A095
Flame proving period 1 (t
FS1
) can be parameterized
to enable the flame on burner 1 to stabilize after the
elapse of safety time 1. Only when the flame proving
period has elapsed will the next program steps be initi-
ated by the BCU. The flame proving period can be set to
between 0 and 25 s.
t
SA1
t
Z
88
02
03
ϑ
t
L1
V1
V2
V3
00
04
t
FS1
1
35
L
51
22
60
61
62
96
82