Operation manual of solar controller SR658
Page 68 of 105
(According the different selected system, see paragraph 4.1,the function will assign to
different output ports)
Under strong solar irradiation, external radiator heat transfer function is designed to release
the excess thermal energy generated by solar system through an external heat exchanger (e.
g. fan coil), aim is to keep the temperature of collector or tank within the operation range. For
this function, an extra output should be added. (system is different, the output relay of circuit
pump RX may be different also, detailed allocation see diagram showed in system
description)
External radiator heat transfer function can either control an additional pump or valve
(
OTPUM ON
= pump logic,
OTPUM OFF
= valve logic).
Heat transfer by pump logic:
If the collector temperature reaches the switch-on temperature(OTST), the heat transfer
pump(RX) on. if the collector temperature falls 5 K below heat transfer temperature(OTST),
the heat transfer pump(RX) off.
Heat transfer by valve logic:
If the collector temperature reaches the switch-on temperature(OTST), the heat transfer
valve(RX) and circuit pump(R1) on. if the collector temperature falls 5 K below heat transfer
temperature(OTST), the heat transfer valve(RX) and circuit pump(R1) off.
Below is the example of this application for reference.
Heat transfer by collector valve logic Heat transfer by collector pump logic
Icon displays on the screen, it indicates that valve heat transfer function is activated.
Icon displays on the screen, it indicates that pump heat transfer function is activated.
