Instruction of SR91 Split Pressurized Solar Hot Water System
Page 11 of 49
corresponding terminals with either polarity.
All sensor cables carry low voltage, and to avoid inductive effects, must not be laid close
to 230 volt or 400 volt cables (minimum separation of 100mm).
If external inductive effects are existed, e.g. from heavy current cables, overhead train
cables, transformer substations, radio and television devices, amateur radio stations,
microwave devices etc., then the cables to the sensors must be adequately shielded.
Sensor cables may be extended to a
maximum length of ca. 100 meter, when cable’s
length is up to 50m, and then 0.75mm
2
cable should be used. When cable’s length is up
to 100m, and then 1.5mm
2
cables should be used.
4. System description (Standard solar system with 1 tank, 1 collector field)
Description:
The controller calculates the temperature difference between collector sensor T1 and tank
sensor T2. If the difference is larger than or identical to the adjusted switch-on temperature
difference, the solar circulation pump (R1) will be switched on and the tank will be loaded
until the switch-off temperature difference or the maximum tank temperature is reached.
