Master Valve Behaviour

[macca]

Hi All,
Firstly I want to thank all involved for an awesome program and the ease of installation was perfect. Very impressive.

I have what may or may not be a niche use case where the default behavior of the master valve doesn't work well for me. I've been running it for a couple of days on my desk, disconnected from my irrigation system to build confidence before wiring it all in and throwing my "dumb" controller in the bin!

Basically when running in sequential mode with master valve selected for my 3 stations I've noticed that the master valve turns off at the same time the first station finishes, then when station 2 starts there is a one second delay for the master valve to restart. Same goes for the next. This wouldn't normally be a problem however I imagine that stopping and starting the big bore pump repeatedly for every station can't be good for the longevity of the pump! Effectively turning one on/off cycle into 3 each time the program runs.

On my current "dumb" controller it leaves the bore running as it switches between stations until it is finished running the complete program. 

So I got around this by going into Options -> Configure Master -> Master Off Adjust = 1 . This now leaves the pump running throughout the program which is great.

Instead now it leaves the pump running for 1 second after it's finished the program and closed all the valves which again will lead to a massive pressure spike just before it turns off, possibly damaging or at least adding wear to the pump.

I'm using the relay_board plugin with a cheapo chinese 8 relay optocoupler board with active low mode.

Any ideas as to where I'm going wrong? Appreciate any advice.

[dan]

An interesting question.

This really needs a modification of the main program code. I'll work on it as there are probably others who would have the same issue.

In the mean time, a possible work around would be to:

Wire an unused relay to the last valve that will be run ( there will be 2 relays attached to that valve).

Set the station for that relay to not activate the master.

Program that station/relay to run as the final station an set the duration for at least one second.

This will allow the pump to stop and the final valve will allow the pressure to be released.

### Edit ###
After giving this more thought and running a quick test you could:

Change to Concurrent mode which allows more than one station to rune at the same time.
Options > Station handling > Un-check Sequential

Set master to None

Program the first valve and the station that controls the pump to start at the same time. (The pump station would need to be in a separate program).

Program the second valve to start at the time the first one stops and so-on for the rest of the valves

Set the pump station's program to stop when the last valve stops.

This could also allow the pump to start a little ahead of the first valve if pressure needs to build first.


Dan

[dan]

Maybe I should have put the added part of the previous post in a separate one:

After giving this more thought and running a quick test, a better solution would be:

Change to Concurrent mode which allows more than one station to rune at the same time.
Options > Station handling > Un-check Sequential

Set master to None

Program the first valve and the station that controls the pump to start at the same time. (The pump station would need to be in a separate program).

Program the second valve to start at the time the first one stops and so-on for the rest of the valves

Set the pump station's program to stop when the last valve stops.

This could also allow the pump to start a little ahead of the first valve if pressure needs to build first.


Dan

[macca]

Great idea. I'll give this a shot and do some testing prior to wiring it in