Using AUX2 to control Air Conditioner

[rwsaustin]

Success! The A/C controller is now working. Need to change title of thread to Using AUX2 AUX1 to control Air Conditioner. I moved relay to AUX1 and used the Waste Not Hi logic with the following set points:

VON: -0.1V
VOFF: -0.3V
ON DELAY: 10 seconds
OFF DELAY: 240 seconds (4 minutes)

The on and off delay effectively solved the short cycle and surge problem I was having with Float Hi setting. As kitestrings pointed out, AUX1 is strictly on or off, whereas AUX2 is PWM.

These settings cause the Classic to turn on the A/C when the charge voltage is 0.1V below the bulk/absorb/float target after a 10 second delay. When the voltage falls to 0.3V below the target, it waits for 4 minutes. If in the meantime, the voltage did not climb back up to the start voltage threshold, it switches off the A/C. The off delay needs to be bigger than the 2 minute start delay of the A/C, else a surge might cause the voltage to drop for a short time. If this drop were to happen beyond the delay time, the surge would cause the Classic to turn off AUX1. The delay effectively ignores the start surge of the compressor. I set the delay at 4 minutes so the compressor would run at least 2 minutes. If we are going to all the trouble to turn it on, we might as well leave it on a couple of minutes. The 10 second delay is a bit of extra insurance against short cycling.

Today, it was 91F and clear after the clouds burned off. The A/C switched on at 11:45 and off at 5:30. CC still read Float, and battery state of charge read full.

I plan to post some photos of my relay box.

[ClassicCrazy]

great  - thanks for the info on how you figured it out.
I have a solid state relay that I will be hooking up soon and will try it out using AUX 1 Waste Not

Larry

[CDN-VT]

Great & Thanks for the report .
2 mins run the load is down from starting , after 4 mins it will be at it's lowest , but that is temperature depended . Use a kill -a-watt or an amp meter .

VT

[TomW]

Success! The A/C controller is now working. Need to change title of thread to Using AUX2 AUX1 to control Air Conditioner.

I tried to do that for you but I don't see how to do a strikethrough in the title.

Tom

[rwsaustin]

CDN-VT,

With my settings, at the end of the day, the A/C will run for a full 240 seconds (4 minutes) after voltage drops to 0.3V below float. I think I am willing to live with that. I have enough battery to run the A/C for at hour or so and still have enough for my nighttime loads.  I will make sure that my float setting is at the upper end of my battery specification.

Does anyone know what will happen if I set VHI to zero? What happens when the voltage reaches the bulk voltage target? Does the Classic then immediately go to absorb? Can I set VHI to 0 and VLO to -0.1? I may also try reducing my Hold delay to something on the order of 130 seconds, just 10 seconds beyond the compressor start-up time delay, but if it causes the A/C to stop cooling for 2 minutes every time a cloud passes by, I think I would prefer to leave the batteries a bit less than fully charged at the end of the day.

The first cold front of the season is due to arrive this afternoon.

Robert

[CDN-VT]

Robert , You'll need to play a bit & write all readings down , give the the time trial a week( the batterys are the ones to reference )  . I just ""TUNED"" in one of systems for summer , Winter ,well cloud & wet rain is the norm. My summer tweak is a few months , so every week I recorded & made slight changes . NOW Im hoping that next summer My recorded settings on the laptop will be uploaded for the summer.
If the Creator / (who ever yur name is ) changes the poles etc. Please keep the fireball as it is. 

VT

[mike90045]

Use the local app to save the register settings to a .CSV format file.

It will be english readable text and very handy to scroll though and to
use to restore after a firmware update

[CDN-VT]

Thats what I use in summer or winter mode . Name all systems & date the files .

VT

[rwsaustin]

Attached are two photos of my A/C relay control box. (Sorry, but the photos are rotated 90 degrees.) The first photo shows the box mounted on the wall. The other shows the relay inside. The outlet on the left is a 12VDC outlet. I routed AUX1 through this into an 1/8" audio jack mounted to the face plate of the outlet. (Behind the wall is a closet, and the closet shares a wall with the battery room.) I mounted a fuse in line with AUX1 in the battery room near the Classic.

The relay box screws to the wall. In the winter, I can remove the A/C from the window and remove the relay box.

The relay is mounted into a gray plastic single gang conduit box. Relay is Dayton 1EJH8. The relay is double pole, so the relay switches both hot and neutral lines. I cut an A/C extension cord in three pieces, discarded the middle piece, stripped the ends and crimped on spade connectors. The relay is bolted to the side of the box. There are strain reliefs on each end of the box, so moving the cables won't wiggle the spade connectors. I mounted a corresponding 1/8" jack on the side of the box. A short patch cable connects the relay box to the wall jack. A short audio patch cable might suffice, but you need to check the current capacity.

It is important that you get an A/C that remembers its state when it loses power. If you can't unplug it and plug it back in and have it come back on to the same setting then my set-up won't work.

My AUX1 Waste Not Hi settings:

• VHI turn on: -0.1V
• VLO turn off: -0.3V
• Start delay: 10 sec
• Hold delay: 240 sec

To do:

• Choose the right fuse for AUX1 protection
• Raise my charge settings to the top end of the recommended voltages for my particular batteries to compensate for the -0.1V VHI setting.
• I may do some math and decrease the magnitude of the temperature compensation so that it accounts for the 0.1V drop in the summer when the unit is connected but not the winter. My battery room hovers around 90F in the summer.
• I have about 1300 square feet of conditioned space. A one ton (12,000 btu/hr) window unit won't cool the whole house. The plan is to install two ductless mini-split units. The window unit was mainly to learn and plan.

[australsolarier]

glad it works out for you.
when you get the new aircons, get INVERTER REVERSE CYCLE SPLIT  air conditioners. they are more expensive to buy and set up (you need a aircon plumber) but much more efficient. they also ramp up slowly and ramp down to almost zero power. (they also have them in 48volt dc versions, but more expensive) besides you can heat with them. some have wifi to turn them on or off. mine remembers the setting. i have one in the shed to keep the battery and electronics cool. if things in there last a year longer, it has paid for itself plus the solar electricity is there anyway.

[CDN-VT]

@
australsolarier
Please take a few pictures of your units .
Also whats the make & model of yours , so I can look up the type you speak of.

VT

[australsolarier]

http://www.ebay.com.au/itm/NEW-Panasonic-CS-CU-Z9RKR-C2-5kW-H3-2kW-Reverse-Cycle-Split-System-/142003073893?hash=item21100af365:g:4CcAAOSwsTxXihoT

something like that,
you just have to do the research what's on the market in the us/canada. the smaller the unit the more efficient they are. the one with wifi is more expensive. there are also remote control extenders that work via the smart phone, a bit pricey though. there are hundreds of different models on the market. keep off made in china, prefer made in korea, japan if possible.
all inverter aircons ramp up and down slowly. they are more expensive than the box ones you install in the window. but also not so noisy and much more efficient, sort of double the efficiency if i remember correctly. they also got timers on them as well.

[CDN-VT]

Thanks , thats what I have & use :
http://www.ebay.com/itm/12-000-BTU-22-Seer-Fujitsu-Single-Zone-Mini-Split-Heat-Pump-System-AC-/272185949996?hash=item3f5f8bff2c:g:RgYAAOxy4c5RrlO9

It's the same type of unit , but called differently .

INVERTER REVERSE CYCLE SPLIT is what got me

VT

[australsolarier]

https://www.youtube.com/watch?v=fVV6GIVc5BA

here my electronics room if you are interested.

[CDN-VT]

Thanks for the View Urs Odermatt.

Thats some wiring .

So you are using PV breakers that open  both Pos+ and NEG- string wires . Double pole ?

VT