IVT Greenline 4 heat pump controller
Hello folks.
Last week I had to make a quick solution, when my neighbour`s heat pump "went to sleep". The originale controller ( CL300 ) had past the way and the company that made this thing, also did the same. So, there we where standing... No spare parts for this machinery. Not that old, abt 10 years. A new heatpump would be a expensive solution, so I decided to give it a try with the Propeller. Afther 2 days with some programming, soldering and adjusting, we had it; BINGO. The heatpump runs all right again.
I used one of this new Propeller Project Board USB as a platform for the project. To this one I soldered a multiconnector and just plugged the whole thing into the connector where the old CL300 stood. Then I could use the old power sypply and I/O interface, since this where a separate card under the CL300 card.
Works great except one little thing : the VGA monitor get a short black-out almost everytime a relay is working. (both, on and off). Not always.
I`ve also seen the VGA monitor get blackout and stay black afther loading the program into the Propeller. Then I need to reset the card, and then VGA starts and works fine.
VGA-connector has 2 rows of pins and is provided by Parallax to fit this cards.
I`m using the vga.text.spin as the driver object, start pin = P16
Could this glitches / blackouts possibly be a result of only 5volts power supply into the Propeller Project Board ???
The manual tells that this boards should run at 5-16V, so I`m in the lower end of the limit scale.
See pictures of the project at my Norwegian homepage: http://home.online.no/~kaare.ar/greenline4varmepumpe.cfm or via: la6wna.com
Last week I had to make a quick solution, when my neighbour`s heat pump "went to sleep". The originale controller ( CL300 ) had past the way and the company that made this thing, also did the same. So, there we where standing... No spare parts for this machinery. Not that old, abt 10 years. A new heatpump would be a expensive solution, so I decided to give it a try with the Propeller. Afther 2 days with some programming, soldering and adjusting, we had it; BINGO. The heatpump runs all right again.
I used one of this new Propeller Project Board USB as a platform for the project. To this one I soldered a multiconnector and just plugged the whole thing into the connector where the old CL300 stood. Then I could use the old power sypply and I/O interface, since this where a separate card under the CL300 card.
Works great except one little thing : the VGA monitor get a short black-out almost everytime a relay is working. (both, on and off). Not always.
I`ve also seen the VGA monitor get blackout and stay black afther loading the program into the Propeller. Then I need to reset the card, and then VGA starts and works fine.
VGA-connector has 2 rows of pins and is provided by Parallax to fit this cards.
I`m using the vga.text.spin as the driver object, start pin = P16
Could this glitches / blackouts possibly be a result of only 5volts power supply into the Propeller Project Board ???
The manual tells that this boards should run at 5-16V, so I`m in the lower end of the limit scale.
See pictures of the project at my Norwegian homepage: http://home.online.no/~kaare.ar/greenline4varmepumpe.cfm or via: la6wna.com
Comments
It does sound like you are having power issues, How many things are driving at once with your power supply?
and what kind of power supply are you using?
-Tommy
Quite likely a power problem. Try using the unregulated power if it is 16V or less and putting a diode and large (1000uF or more) capacitor between the unregulated supply and the project board input.
PS - I am surprised to see a heat pump being used that far north. What is the average winter temperature there?
Tommy:
The power supply unit is the one that supplied the old proceccor card. Unregulated it is abt 15V, and it has 2 x 1000uF cap`s in parallell. This side of PSU only drives 3 relays. The connection between Propeller and the relays, are a Darlington-array IC wich where standing there before. At the 5V side, the PSU only supply the Propeller card and a ADC0834 with 4 LM35 temp sensors.
kwinn:
Yes, I may try to supply the PPBoard with higher voltage. Reason I have not tried this yet, is the ADC0834 wich I soldered on the PPBoard and gets 5v from there.
I have to get the 5v directly to the ADC and then supply PPBoard with 15V. The proceccor and heatpump runs OK , not affected by this, so I`ll see if I give it a try later.
(PS) . Well, I dont know the average winter temp here, but most of the days we have temperatures between -10 and +5 C Somedays may be as cold as -30C, but they`re wery few.:blank:
Note that this heat pump is type water-water. The collector is a 300m long tube, buried abt 1,5 meters below ground surface and filled with Glycole fluid. So the input temp is stable around 2-5 degrees C. Output from heat pump goes to the floor heating water system. This system is combined with an accumlator-tank and a wood-stove with water heating system included.
Well, since all the VGA output pins from the Propeller never will exeed 3,3V, I thought it was strange that 5V PSU would affect the VGA performance.. But this may be the problem as well.
Thanks again for reply.
I have seen this type of problem many times, and it is usually caused by one of two things. Either the input voltage to the regulator drops low enough that it can no longer maintain the regulated output voltage, or the noise spikes from a relay, motor, or other inductive load will pass straight through the power supply to the circuit it is powering. In both cases the symptoms can be very unusual. It may reset or lock up the entire system, or it may only affect a small section of the circuit.
When the input voltage drops and causes the regulator output voltage to drop adding a diode and capacitor between the input and the regulator will usually fix the problem.
When it is noise spikes getting through the power supply the added diode and capacitor may work, or it may not. Sometimes it takes a good filter circuit and TVS to solve the problem.
While switching regulators are great from an efficiency and power output perspective when compared to linear regulators they are more susceptible to electrical noise. The large iron core, numerous turns of copper wire, and large capacitors used in linear supplies do a better job of absorbing the spikes than the much smaller capacitors and inductors used in switchers.
There are several reasons they are popular in Norway.All (or very nearly all) heating in private homes is by electricity anyway (but extra wood stoves are also relatively common outside of apartment homes). So it makes a lot of sense to replace the traditional electrical heating with a heat pump, given the efficiency you get these days. And as houses in Norway are very well insulated (by construction regulations) it's possible to easily heat a whole floor with a 6 or 7KW heat pump, even at mid-winter. You'll save on electricity even when very cold. I use the wood stove to help the heat pump a bit if it drops down to -15C or colder, which would be unusually cold near the cost, so so far I haven't used it at all yet this winter. Before the heat pump I used the wood stove every day.
-Tor
Kwinn: Thanks for the tip about using a cog for watchdog funktion. I`ve thought about the same thing, but since the system is running all right as is, I think I let it be this way.Its been running for almost 14 days now, and not showing any hang or lock-ups or other malfunction related to the program. I`m really satisfied with this project.
I had to do a minor adjustment to the spin code afther a week or so, because of "Alarm 5", which is the alarm for too high input water temp to the heat pump. Everytime my neighbour put a fire in his wood-stove and the tank temp where rising, this alarm tripped. (setpint 51C) This occurred even the circ.pump to the tank where turned off. (stops at 48 C) Reason to this is that the water is self-circulating caused by the temp difference between tank top and bottom. The heat pump circuit should have been equipped with an one-way valve to prevent this happening. Instead, I made the Alarm5 auto-reset, which takes the system back into normal run when the input temp cools down to abt 47C. I made this to ensure the heat pump starts again without manually reset, because the alarm5 is not critical.
Yeah Tor, youre right. The heat pumps have become VERY popular here in Norway. I will say the demand of this have nearly exploded over the last decade. You see them on every house wall. Most common is the air-air units. They become more and more efficient everyday. In newer houses, you may see more of the air-water units. This because nearly all new houses here in Norway have installed waterborn heating systems. In my house, I only have the "good old" electric heating cables in the floors. Damn me... Whish I had waterborne heating system.... I use a whole lot of wood in the stoves at wintertime.:blank: When its raining, I use the heating cables. Whatfore???, you`ll say...
Well, I made myself a micro powerstation in the creek beside of my house. Gives me 1,7kW of free electricity, an cut my electricity bill with about 5.000,-/year. Fun...
But that`s another project. I`m thinking of using a PPBoard to make a monitoring system for the powerstation and get the data into my spinneret webserver becide my other installations. See them at: http://spinneret.la6wna.com/ if the server is running.
Have fun!