Steca TR A301 PWM

3 inputs, 1 PWM output


The Steca TR A301 PWM controller was designed in particular for the use of highly efficient, cost- and energy-saving pump technology for solar heating systems. These latest generation pumps are electronically commutated motor circulator pumps with integrated frequency converter and permanent magnet motor. To control such a high-efficiency ECM pump, a special control via a PWM control signal is required. With this pulse width modulated square-wave DC voltage, the Steca TR A301 PWM controller can automatically and precisely adjust the speed of the pump to the continuously changing requirements of the system via a separate control line.

In addition to PWM speed control of the solar circuit pump, the Steca TR A301 PWM also offers the option of performing hydraulic balancing of the solar system using Grundfos Direct Sensors™.

The visualisation of the operating status as well as the complete solar circuit is handled by the clear display with graphical animation. The consistent use of pictograms facilitates the easy operation of the controller.

The controller also takes over important system monitoring and safety functions, ensuring the continuous and safe operation of the entire system.

System operational safety is supported by sophisticated fault diagnostics. The multicoloured LCD backlighting ensures that any faults that have occurred can be found quickly and reliably, helping to quickly rectify any faults.

Steca TR A301PWM technische Zeichnung


Product features

  • Compact, multipart designer casing
  • Electronic speed control via pulse width modulation (PWM)
  • Maximum storage tank temperature
  • High level of operational safety through fault diagnosis
  • Logging of minimum and maximum temperature values
  • Temperature display °C / °F
  • Collector overtemperature disconnection
  • Hours-of-operation logger
  • Storage tank target temperature loading
  • Spring clamp terminals allow rapid and easy installation
  • Flow rate and temperature display using Grundfos Direct Sensors™


  • Graphical LC display with backlighting
  • Animated representation of the systems and operating states


  • Non-verbal menu navigation
  • Side switch for manual, auto, off


  • Flow rate acquisition for hydraulic compensation
  • Holiday (storage tank recooling)
  • Interval / tube collector
  • Anti-freeze


  •  Steca TR A301 PWM certificate CE · pdf · 1.071 MB
  •  Steca TR A301 PWM productdatasheet DE · pdf · 0,938 MB
  •  Steca TR A301 PWM productdatasheet EN · pdf · 0.938 MB
  •  Steca TR A301 PWM manual DE · pdf · 3.294 MB
  •  Steca TR A301 PWM manual EN · pdf · 3.747 MB
  •  Steca TR A301 PWM product pic drawing · jpg, 300 DPI, high quality · 0.441 MB
  •  Steca TR A301 PWM product pic drawing · jpg, 72 DPI, web quality · 0.234 MB

Technical data

 TR A301 PWM
System voltage
230 V AC (± 15 %), 50 Hz
System voltage optional
115 V AC (± 15 %), 60 Hz
1.07 W
Temperature control class
Energy efficiency
1 %
Number of inputs
2 x temperature (Pt1000), 1 x Grundfos Direct Sensors™ VFS 1-12 (temperature / flow rate)
Number of outputs
R1: switched triac output for pump power supply, max. 250 W (230 V); C: PWM control signal for pump speed, 8 mA; 5 V; 250 Hz
Turn-on temperature difference
8 K
Turn-off temperature difference
4 K
Ambient temperature
0 °C … +45 °C
Degree of protection
IP 20 / DIN 40050
Dimensions (X x Y x Z)
134 x 137 x 38 mm [0.00 x 0.00 x 0.00 inch]
250 g [0.00 oz]
    Thank you, your request has been sent

    Your request:

    * = mandatory field

    Product comparison

    Not yet able to see all the products you want in the comparison list?
    Add more products

    How it works:
    Open a product group and add the product to the product comparison using the "+ Compare product” button.