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Simple solar controllersolar array controller, charging pump controller, swimming pool controller

Abmessungen [mm]:

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 InputsInputs: 3Icon OutputsOutputs: 1+1Icon DL-master
Icon InterfacesInterfaces: DL-Bus

Detail information

  • 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, ESR31-D
  • Program-dependent expansion option with auxiliary relay HIREL-STAG (e.g. error message


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