Created description based on simulation.

LOGIC COMPONENT is defined.

Will a latch be necessary to retain inputs during exchange cycle?

7477 Latch is in new simulation file.


LTC 1042 WINDOW is the WHILE(OK) DO.

WHILE (OK) DO {
 
  IF (UD && _READY) THEN PUMP(0)  

  ELSE IF (_UD && READY)  THEN PUMP(1)
 
 } ALARM

READY IS the high collector threshold, 160º Fahrenheit typical.

555 continuously asserts ON phases but does not pump unless USER DEMAND is TRUE, OR if READY is TRUE AND UD is FALSE. THIS CREATES a heating time period to fulfill USER DEMAND before discharging any heated water at 160º Fahrenheit into a secondary tank or location.

ITS A nice project, asserting simulation to verify critical operation and logic of the control, which as it turns out is not too complex, and will be both inexpensive and easily manufactured.

DESCRIPTION:

Solar Collector circuit uses 555 timer to continuously apply duty cycle clock periods to

LOGIC PUMP_ON input. ON PERIOD should match time needed to exchange collector

absorption water or other fluid. WINDOW SETS low & high pump thresholds. TANK is the primary ZONE.

WHILE T_SENSE is greater than USER setting threshold, AND collector water temperature measured via C_SENSE2 is less than C_THRESHOLD setting, typically 160º Fahrenheit, NO PUMPING can occur.

WHILE collector temperature via CSENSE measures within window; 120º to 180º Fahrenheit. DO

{

IF T_SENSE measures below USER setting threshold, the next timer PUMP_ON cycle will exchange heated collector and primary tank water.

ELSE IF T_SENSE measures above USER setting threshold, AND collector water temperature CSENSE measures above C_THRESHOLD so that ZONE toggle SELECTS secondary ZONE pumping can then occur, exchanging heated collector water with secondary ZONE.

}

IF CSENSE exceeds 180º Fahrenheit, no pumping can occur, and ALARM condition may

also open a safety valve.

THIS WAY, a low cost solution creates inherently variable absorption period, as well as

safety features for DIY possible SOLAR COLLECTION.

SIMPLIFIED ALGORITHM:

WHILE (OK) DO {    

 IF (UD && _READY) THEN PUMP(0);

 ELSE IF (_UD && READY)  THEN PUMP(1);  

 } ALARM

SIMPLE

REVISED LOGIC COMPONENT, DEFINED WINPLD design file for g16v8a PLD.


CREATED LTSpice logic component based on g16v8a target.