D-LX 110

Compact flame monitor

Self-monitoring and fail-safe compact flame monitor for the monitoring of gas, oil and coal flames with integrated UV, VIS or IR flame sensor, primarily in single burner view applications.


  • For ambient temperatures from -40°C up to +75/70°C, certified and without need for accessories to isolate, heat or cool.
  • Highest safety combined with highest availability
  • Ideal support for Functional Safety within safety chains up to SIL3
  • Flame relay output as changeover relay (SPDT, 1 x NO, 1 x NC)
  • All variants of the D-LX 110 also available for combination with fibre optic systems (see D-LX 710)
  • Easy exchange of consumables
  • Local display of settings and operational status for the whole ambient temperature range, visible for all versions at a single glance

Your Benefit

  • Easy adjustment
    The easy access to the available adjustments shortens time for commissioning
  • Versatile detection
    The choice of available detectors allows for the monitoring of flames of all fuels within the same device family
  • Versatile for the most variable application conditions
    The same device technology can be used without change for the most different geographical regions and based on varying systems of standards
  • Flexible for changed requirements
    If the requirements of the plant change (ex, zones, need for fibre optic systems) it usually is possible to adapt via a replacement within the same device family
  • Flexible operation support 
    The possibility to adapt device settings also outside the factory enables fast local replacements with smaller stocks of replacement devices


Technical Data

Operational modeIntermittent operation or continuous operation
SafetySelf-monitoring and fail-safe,
supports safety chains up to SIL3
Electrical connection24 VDC, 7W, PELV
Flame relay1x NO contact, 250 VAC, 2 A
1x NC contact, 250 VAC, 2 A
Status relay1x NO contact, 250 VAC, 2 A
Flame Failure Detection Time (FFDT)0.5 ... 5 s (adjustable in steps of 0.5 s)
Analogue output0/4...20 mA, 750 Ohm max.
Spectral rangesUV, VIS, IR
Number of ranges1
Threshold switchFlame intensity
Viewing angle
6° horizontal, 12° vertical (D-LX 110 UL)
CommunicationLEDs, always visible at a glance for all versions
Perm. ambient temperature-40...+75°C
-40...+70°C (D-LX 110 UL)
Sighting tube connectionG 1¼" or 1¼" NPT(F)
Purge air connectionG ½" or ½" NPT(F)
Protection classIP66/IP68, NEMA 4X
IP65, NEMA 4X (/MP7)
Dimensions100 x 100 mm, length approx. 260 mm (housing M5)
Weight (w/o cable)approx. 1.3 kg (housing M5)
Ex protection
D-LX 110 ../M4/84ExII 2G Ex db IIC T6 or T5 Gb
II 2D Ex tb IIIC T85°C or T100°C Db
D-LX 110 ../M4/85ExCl. I, Div. 1, Gr. A, B, C, D T6/T5
Cl. II, Div. 1, Gr. E, F, G T6/T5; Class III
Type 4
Hazardous locations: indoor/outdoor
D-LX 110 ../M5/86ExCl. I, Div. 2, Gr. A, B, C, D T6/T4
Cl. II, Div. 2, Gr. E, F, G T6/T4; Class III
Type 4
Hazardous locations: indoor/outdoor
D-LX 110 ../M5/87ExII 3G Ex ec nC IIC T6 or T4 Gc
II 3D Ex tc IIIC T80°C or T130°C Dc
Sighting tube connectionG 1¼"
Protection classIP66, NEMA 4X
DimensionsØ120 mm, length appr. 310 mm
(/M4/84Ex, /M4/85Ex)
100 x 100 mm, length approx. 260 mm
(/M5/86Ex, /M5/87Ex)
Weight (w/o cable)approx. 3.0 kg (/M4/84Ex, /M4/85Ex)
approx. 1.3 kg (/M5/86Ex, /M5/87Ex)


  • Digital display for optimal adjustment of the flame sensors by measuring the pulse rate and its extreme values (D-ZS 087-20)
  • Set of apertures for insertion in purge air flange (D-ZS 113 Set)
  • Optical adjustment aid for the alignment of the Swivel mount on the sighting tube (D-ZS 118)
  • UV-C test light source 230 V / 50 Hz (D-ZS 077-10)
  • UV-A, UV-B and IR test light source 230 V/50 Hz (D-ZS 093)
  • Swivel mount for alignment of flame monitor to the flame to be monitored (D-ZS 033-I)
  • Thermal isolator with electrical insulation (D-ZS 117-I)
  • Ball valve for closing sighting tube (D-ZS 133-I)
  • Terminal box for connecting the flame monitor (D-ZS 140-12 / 141-12)
  • Wide range power supply unit for supply of several D‑LX 110 (D-NG 24/25a)