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Abmessungen [mm]:

Simple solar controller

Icon solar array controller, charging pump controller, swimming pool controller

The ESR21 unit is a multi-purpose differential controller. Additional information can be read in via the DL bus. Thus, in parallel to the controller operation (solar system) it is also possible to calculate the yield (thermal energy). The range of use extends from the single circuit solar system through to sanitary water treatment by way of pump speed control.

Icon DL-masterIcon InputsIcon OutputsIcon Interfaces
  • 1 relay or triac output
  • 1 control output: PWM / 0-10V
  • 17 different programs can be set
  • Status display for system malfunctions
  • Solar start function, frost protection function
  • Pump blocking if a collector overtemperature exists
  • System function control
  • Heat meters
  • DL bus for data evaluation on the PC via C.M.I. and for connection of external sensors
  • Speed control of high efficiency pumps via control output PWM / 0-10 V
  • Speed control of standard pumps: ESR21-D
  • Program-dependent expansion option with auxiliary relay HIREL-STAG (e.g. error message


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