Staged Control With Pre-Purge - Honeywell KromSchroder IC 40 Technical Information

Application
P A
22 3 5
12
V1
VAS VAG
VAG
DI 1
4
IC 40
BVA
IC 40 · Edition 07.18
L1, N, PE
P
PLC
23 4
BCU 460..L
µC
9 26
DI 2
7
M

1 .1 .4 Staged control with pre-purge

The central control system starts the pre-purge. Input
DI 2 is activated via the air valve output of the BCU and
the butterfly valve BVA is set to the pre-purge position.
In the event of a temperature demand, the burner con-
trol unit BCU activates input DI 1 via the valve output
V1 and moves the butterfly valve to the ignition position
(precondition: the IC 40 must have reached the ignition
position on the instant of ignition). The burner starts.
To activate the high-fire rate, DI 2 is actuated via the air
valve output on terminal 26 of the BCU.
18
19
The butterfly valve moves cyclically between the high-
16
fire rate position and the low-fire rate position (see
17
Operating mode 11, 2-stage operation with two digital
inputs).
DI 1/V1 DI 2/air valve
Off
BIO/
On
BIC
On
Off
IC 4 position
Off closed
Off low Ignition position/low-fire rate
On middle
On high
Valve position
Closed
High-fire rate
Pre-purge
8