this puppy is frying my brain. I have;
- Altered the resistances at the pots and brought them to the levels for -8°C (the evaporator temp where the thermistor is located. I increased the two 5V setting in the Thermistor model to 6.5V the OFF temp for 0°C. Is this correct?
- Inserted the Triac as per the MOC data sheet but could not find the identical one. Note how current continues to flow in the OFF period? When increasing the value of R15 from the data sheets 39R to 100k I can get the current to stop flowing on the OFF period, is this right?
- Have altered the heater resistance to 275R (the heater is 175W). The heater should draw 0.8A, the circuit is drawing about 1.15A, is the resy going into the circuitry?
I hope I am getting somewhere, I need some help please!
I would not recommend it.Hi,
excellent, would this be a good idea to maintain this residual current?
At 100n little happens
so we are in the finishing straight ........
Must I bring about the changes you recommended this morning or keep with the original circuit now that we have the 0.01 cap issue sorted out. In hindsight will be reverting to your original suggestion to power the unit off 220V from the inverter so I will need to bring about changes to the board in any event.
I am extremely excited about bringing this project to a conclusion. If it is as successful as I believe it will be then I would like to post it in the projects section.
Will this be significantly more design work for you? If the design is not finalised before you leave for S.A. I am unable to carry on. The idea sounds great as the accuracy will improve.
I will not have time to complete before I travel, I would be happy to restart in the New Year on Ver2 with proportional heating control.
You have plenty to do so really I am in your hands as I don't have the skill. If you are OK with it i'm in.
Am I correct in stating that the circuit as it currently set works by pulsing the heater in very short bursts of about 100ms on and 60ms off.
No, its either On or Off depending whether the tempr of the fridge is cold or warm, as it was in the original design
This is because we have set the time between any voltage change at the thermistor at intervals of 0.1 sec. In reality this time frame is probably too short for any response from the thermistor so the pulses would be a little less frequent?
Not applicable without proportional Triac control on this version.
hi Andrew.Hi Eric,
have an awesome holiday. Soak up the sun, swim in the sea, drink copious quantities of of favourite beverage and most of all enjoy the country I hold dear.
If we don't speak again before you leave then I wish you safe travels and may you have a wonderful X-Mass and great New Year.
So proportional control is the New Years project, you're on. Will complete this one in the interum period and will report back.
Many thanks once again.
PS: It is not that I don't read your posts it is that I don't always fully comprehend. Electronics is so far out of my aptitude comfort zone it's simply not funny. I am enjoying it though.