1
Gas Burner Safety Control
DKG 972
INTRODUCTION
The burner control box DKG 972 controls and supervises
atmospheric burners for gas. They are approved and certified
according to the applicable European standards and
regulations.
The microprocessor-based programming sequence ensu-
res extremely stable timings independent of voltage varia-
tions, ambient temperature and/or switch-on cycles. The
built-in information system not only provides a continuous
monitoring of the actual state of the box (very helpful es-
pecially for monitoring the start-up phase) but also informs
about the cause of a possible lock out. The lock out cause
is stored in such a way that it can be retrieved even after a
power failure.
The control box is designed for maximum safety in case of
fluctuations in the voltage supply. If the mains voltage drops
below the permitted level, operation is interrupted and the
control box automatically prevents the start sequence from
being repeated. In this way, the safety of the system is not
put at risk by a drop in the mains voltage. This low-voltage
protection works not only during start-up but also perma-
nently during operation.
CONSTRUCTIONAL FEATURES
The control box circuitry is protected by a flame resistant,
transparent plug-in type plastic housing. A central fixing
screw locks the control box to the wiring base.
The plug-in control box incorporates the microprocessor
based timer, flame check and reset circuits.
Manual reset from lock out and set to lock out is provided by
a push button with an integrated LED information system.
A variety of cable entry points provides complete flexibility
for electrical wiring.
The wiring base S98 is equipped with spare- and extraterminals
and allows together with a variety of cable entry points utmost
flexibility of electrical wiring.
The DKG 972 are compatible with the TFI 812.
Different are only the pre- and post-ignition times.
Max. heating power according the limits in the Gas Appliance
Directive.
TECHNICAL DATA
Operating voltage
220 / 240 V (-15... +10%)
50 Hz (
±
5%)
or
110 / 120 V (-15... +10%)
60 Hz (
±
5%)
Fuse rating
10 A fast, 6 A slow
Power consumption
ca. 12 VA
Max. load per output
- term. 3 ignition trafo
1.0 A, cos
ϕ
0.2
- term. 5 + 6 solenoid valves
0.5 A, cos
ϕ
0.4
- term. 7 alarm indicator
0.5 A, cos
ϕ
0.4
- term. 4 auxiliary blower
2.0 A, cos
ϕ
0.4
total load
4.0 A, cos
ϕ
0.4
max. 16 A during 0,5 sec
Reset time from lock out
none
Re-cycling / repetition (max. 4x) after a loss-of-flame during
operation
Sensitivity
1
µ
A
min. ionisation current required
1.5
µ
A
Sensitivity for stray light
0.4
µ
A
Ionisation probe insulation
probe - earth
greater than 50 M
Ω
Stray capacitance
probe- earth
less then 1000 pF
max. cable length
< 3 m
Flame detectors
IRD 1020.1
side-on or end-on viewing
UVD 971
end-on viewing
Weight incl. Wiring base
190 g
Mounting position
any
Protection class
IP 40
Approved ambient parameter
for control and flame detector
max. 95% at 30
°
C
- for operation
-20
°
C... +60
°
C
- for storage
-20
°
C... +80
°
C
Build-up of ice, penetration of
water and condensing water are
inadmissible
Approvals according
to European standards
EN 298 and EN 230, as
well as all other relevant
Directives and standards
Classified acc. to EN 298
ATLLXN
For 2-stage atmospheric gas burners
Flame detection:
- Ionisation probe
- Infrared-flicker detector IRD 1020.1
- UV flame sensor UVD 971
Model
waiting time start
pre-ignition time
Stray light monitoring
safety time
post-ignition time
delay 2nd-stage
tw
tvz
tf
ts
tn
tv2
05
12
3
5
5
4
25
10
12
3
5
10
9
25
Table of timings (sec.)
EN1C-0127SZ20 R0305