SG10080501
CONTROL BOX
DMG970
INTRODUCTION
The burner control box DMG 970 controls and supervises forced draught burners for gas and dual fuel.
The microprocessor programming sequence ensures extremely stable timings independent of voltage variations,
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 (including monitoring of the start-up phase) but also informs about the
possible cause of a lockout. The lockout 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 permanently during operation.
LOCK-OUT IDENTIFICATION
In the case of a failure the LED is permanently illuminated. Every 10 seconds the illumination is interrupted by a flash
code which indicates the cause of the error. The following sequence is performed and is then repeated as long as
the unit is not reset.
FLASH CODES
ERROR MESSAGE
POSSIBLE FAULT
within lock out safety time no
flame establishment
stray light during startup
detector may be faulty
loss of flame
stray light
air pressure switch opened
during operation
loss of flame during operation
air pressure switch contact
welded
air pressure switch timeout
air pressure switch does not
close within specified time
FLASH CODE
air pressure switch opened
lock out safety time
air pressure switch closed
illuminated phase dark phase Flash-Code dark phase
for 10 sec for 0.6 sec for 1.2 sec
SEQUENCE TIMINGS
tlw
Max. reaction time for air
proving switch
60
tv1
Supervised pre-purge time
40
tvz Pre-ignition
time
3
tz
Ignition time total
5.5
ts Safety
time
3
tv2 Delay
2nd-stage
12.5
SEGMENT
OPERATION
DURATION (S)
tlw tv1 tvz tz ts tv2