BCU 580 · Edition 11.15
14
1 .1 .7 ON/OFF rotary impulse control
For processes which require a turndown
of more than 10:1 and/or those which
require heavy circulation of the furnace
atmosphere to ensure a uniform tem-
perature, e.g. heat treatment furnaces
operating at low and medium tempera-
tures in the metallurgical industry.
With ON/OFF cyclic control, the capacity
supplied to the process is controlled by
means of a variable ratio of the operat-
ing time to the pause time. In this type of
control, the burner output pulse frequen-
cy always maintains full momentum and
results in maximum convection in the
furnace chamber, even with regulated
heating.
The pneumatic ratio control system con-
trols the gas pressure on the burner pro-
portionally to the air pressure and thus
maintains a constant air/gas ratio. At the
same time, it acts as a low air pressure
protection device.
The ignition and monitoring of the pilot/
main burners is ensured by burner con-
trol units BCU 580.
The centrally checked safety functions
such as pre-purge, tightness test, flow
detector and pressure switch check (gas-
min.
, gas
max.
, air
min.
) are provided by the
FCU 500.
Application > Examples of application
M
PZL
PZH
PZ
PZL
PDZ
TE
BCU 580..F3
FCU 500..F0
µC
P
DG
DG
DG
VAS
VAS
VAS
VAG
VAS
VAS
VR..L
VR..L
DG
DG
DG
min
DG
max
49
15
13
14
50
45
47 48
58
>750°
p
u
/2
ϑ
1
46
2
3
DL
min
DL
Purge
BCU 580..F3
VAG
VAS
VAS
M
STM