SUNFLOWER SR868C8 - Nmin Solar Circulation Pump Speed Adjusting (RPM Speed Controlling); DTS Standard Temperature Difference; (For Circuit Pumps Speed Adjusting); Nmin Solar Circuit Pump Speed Adjusting（Rpm Speed Controlling

Operation manual of solar water controller SR868C8/SR868C8Q
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► Press “ESC” button to exit the menu or wait for 20 seconds to exit automatically,
parameters are saved automatically.
4.6.3 nMIN Solar circuit pump speed adjusting（RPM speed controlling）
Note: SR868C8 doesn’t have this function
Description:
P1 output can be configured to function either as RPM controlled output or simple
switch output. When this function is activated, the output is RPM controlled output;
when parameter is set as “nMIN”100%” the output becomes a normal switch output.
Normal switch output: circuit pump speed controlling is deactivated, pump is
operated with a fixed speed, and flow rate is not changed.
RPM control output: (speed controlling is activated), the control system attempts to
maintain a constant temperature difference between collector and tank. The pump
performance is continuously adjusted and the volume flow pumped is increased or
reduced, depending on the temperature difference.
Setup steps:
To access main menu FUN, then select submenu nMIN, “nMIN 30” displays on screen.
►Press “SET” button, parameter “30” blinks on
the screen
►Press “+”“-” button, to adjust speed of circuit
pump, adjustable range (30～100%), factory
set is 30%
► Press “ESC” button to exit the menu or wait for 20 seconds to exit automatically,
parameters are saved automatically.
4.6.3.1 DTS Standard temperature difference（for circuit pump’s speed adjusting）
Note: SR868C8 doesn’t have this function
Description:
When the switch-on temperature difference (△T ON) reaches, solar pump is triggered,
and then within 20 seconds, pump speed reaches to its minimum speed (30%).
Whereafter, controller checks continuously, when the standard temperature difference
(DTS) reaches, the speed of pump increases one grade (10%), temperature difference
RIS increases every 1
o
C, speed of pump increases 10% until it reaches to its maximum
speed 100%. Through setting the temperature difference increase rate (RIS) can