SELEKTA 172 top2 24V


  • Astronomical time switch with weekly program
  • 2 channels
  • 84 memory locations
  • Channel 1 or channel 2 can also be used purely as time switch channel
  • 2 external inputs
  • Connectable sensors (external selector switch, sequence timer, staircase light function)
  • Connectable switches (ON or OFF permanent switching, astronomical or special program)
  • 3 special programs with yearly date function per channel
  • Fixed public holidays or date ranges and public holidays dependent on Easter
  • Astronomical times with other night interruption / fixed ON switching
  • permanent ON or OFF switching
  • Count-down timer
  • Astronomical time switch function (automatic calculation of sunrise and sunset times for the whole year)
  • Offset for adjusting of sunrise and sunset times
  • Position data via coordinates or country/city lists can be programmed
  • Fixed ON-OFF switching times can be programmed (e.g. night time interruption)
  • Simulation of switching times (calculated astronomical times and programmed ON/OFF switching times)
  • Reversible astronomical mode (evenings ON - mornings OFF or evenings OFF - mornings ON) or can be deactivated
  • DuoFix spring terminals
  • For 2 conductors each
  • Wire or strand (with or without wire end sleeve)
  • Wire diameter: 0.5 - 2.5 mm²
  • Button for releasing plug-in connection
  • Text-oriented user guidance in display
  • Preset date and time
  • fully operable without mains connection
  • Interface for OBELISK top2 memory card (PC programming)
  • 2. insertable switching program
  • Copying programs
  • Storing programs
  • 10 year power reserve (lithium battery)
  • Zero-cross switching for relay-saving switching and high lamp loads (not with 24 V devices)
  • Calculated astronomical switching times
  • Programmable ON-OFF switching times
  • Switching preselection
  • Permanent switching ON/OFF
  • Integrated operating hour counter
  • Reset option
  • Service function for monitoring maintenance intervals
  • Holiday program
  • Display back light (can be turned off)
  • PIN coding
  • Automatic summer/winter time changeover
  • can be deactivated
  • Date rule options are already stored for Europe, the USA and other countries
  • own date rule options or changeover around set dates are available

Technical data

Operating voltage 12 – 24 V UC
Frequency 50 – 60 Hz
Width 2 modules
Installation type DIN rail
Type of contact Two-way changeover contact
Switching output Phase-independent
Opening width < 3 mm (µ)
Program Weekly program, Astronomical program
Program functions ON-OFF
Number of channels 2
External inputs 2
Number of memory locations 84
Power reserve 10 years
Switching capacity at 250 V AC, cos φ = 1 16 A
Switching capacity at 250 V AC, cos φ = 0,6 2 A
Incandescent/halogen lamp load 230 V 1400 W
Energy saving lamps 230 V 30 W
LED lamp < 2 W 6 W
LED lamp 2-8 W 20 W
LED lamp > 8 W 25 W
Fluorescent lamp load (electronic ballast) 180 VA
Switching capacity min. ca. 10 mA
Shortest switching times 1 min
Time accuracy at 25 °C typical ± 0,25 s/day (quartz)
Time basis Quartz
Stand-by consumption ~0,2 W
Memory card supplied
Type of connection DuoFix spring terminals
Externe Antenne anschließbar
Keyboards 4 touch buttons
Housing and insulation material High-temperature resistant, self-extinguishing thermoplastic
Type of protection IP 20
Protection class II according to EN 60 730-1
Spannung 12-24 V UC
Ambient temperature -30 °C … +55 °C

Connection example

SELEKTA 172 top2 24V

Scale drawings

SELEKTA 172 top2 24V


Article number Data sheet Documents basket
Wall mounting kit 35 mm - Terminal box cover plate for assembly, sealable

Wall mounting kit 35 mm

PC set OBELISK top2/3 - Switching programs created on the PC by means of the convenient OBELISK top2/3 software can be transferred
                                 via USB interface to the OBELISK top2 memory card or the Bluetooth OBELISK top3 and from the card to the time switch and vice
                                 versa. Thus no PC or laptop is required on-site. Programming and the program printout can be done comfortably from the desk

PC set OBELISK top2/3

Memory card OBELISK top2 - Individual memory card

Memory card OBELISK top2

Front panel kit - The front panel installation set is suitable for Theben distributor installation devices of 17.5 to 107.5
                                 mm width

Front panel kit



Format Download
Operating instructions (smartphone) PDF
Operating instructions PDF
Tender texts DOC
Manual PDF
Software ZIP


Article number Data sheet Documents basket
SELEKTA 172 top2 - Astronomical time switch with weekly program

SELEKTA 172 top2

SELEKTA 172 top2 24V - Astronomical time switch with weekly program

SELEKTA 172 top2 24V

  • 24 V UC
Article number 1724100
Data sheet
Documents basket