We have combined some zones by hooking together 2 or sometimes 3 valves in the same area to shorten our total watering run time. Pressure isn't a issue but wondered if this could potentially cause any problems to the controller since it will now be sending voltage to multiple valves plus the master valve. Has anyone had issues with this?
Operating multiple valves on one zone
kcdas
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I think it would matter in the sense of matching the controller output to the anticipated loads, especially in case of a controller being installed in an older system that was once operated by an electromechanical controller, and may have valve solenoids with heavier current draws than current production.
Obviously, solid state electronics can go Phhht!! quicker than an eyeblink, but I do know that triacs that switch controller outputs have half-cycle ratings far above controller "circuit breaker" trip points, so my duration question was looking at whether there are any happy mediums where a triac can have a safe operating current for the fraction of a second it takes for the solenoid plunger to lift into place, which would be the point where opening surge becomes steady-state operation.
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Word on the street is Rainbird has an entire department devoted to addressing systems once operated by electromechanical controllers and solenoids of higher load requirements than now. Even though it's a small department, they're dedicated.
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If I understand your point, then I will respond by saying that our triacs can handle more current than the transformer can supply. So, damaging triacs by turning on too many solenoids at once is not an issue. The transformer limit will be reached sooner than the triac will be damaged.
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Obviously, the triacs should handle anything the transformer can supply. It's when we do the simple math and see that three solenoids powered simultaneously will never put a 20 VA rated supply transformer in jeopardy, that we wonder why a controller won't accommodate them.
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Any controller operating a MV is running 2 valves at the same time, only difference is the delay between MV and zone.
OP mentioned 2+ valves in addition to MV and that is what I was referring to. I've worked with controllers on golf courses that were designed to operate multiple valves at the same time.
Any controller operating a MV is running 2 valves at the same time, only difference is the delay between MV and zone.
OP mentioned 2+ valves in addition to MV and that is what I was referring to. I've worked with controllers on golf courses that were designed to operate multiple valves at the same time.
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Golf course controllers are specialty controllers which can run many more valves at one time than conventional residential/commercial controllers.
Hunter pilot for example can fire up to 3 valve in head rotors per station and up to something like 20 stations at a time.
That means something in the area of 60 solenoids can be actuated at the same time.
(Copied from sprinkus- I can't find the really awesome solenoid thread a few years back )
Solenoid Inrush Measurement
Inrush Current. It is the current required to generate sufficient magnetic force to pull the plunger or overcome the air gap.
If there is any fluid inside the solenoid, the air gap is filled with water which exerts certain amount of pressure on top of the plunger.
We need to know what is the force/pressue exerted on top of the plunger .
F1=P/A
P=water pressure
A= Area of the Plunger where water pressure is exerted.
F1= Force on top of the plunger.
Now the Magnetic force required to pull the plunger is
F= F1+FP
FP= is the weight of the plunger.
Based on the net force which is the required magnetic force use Maxwell force formula:
F = ( Fm)2 μ0 A / (2 g2)
In order to calculate this, you should know the magnetic permeability of the solenoid, material, number of turns in the coil, cross section of the coil ,or the magnet wire Inductance,etc.
The INRUSH does depend on the water pressure and efficiency of the solenoid.
------------------------------
Math aside
I walk into 1000+ systems a year . I often will see a system with MV and 2 zones wired up. Rarely I'll see 3 valves wired into the same port ( no MV)
In my experience in residential- It is very rare that I determine an electrical issue to the controller /fuse has been caused due to additional valves on the same circuit . I have many many more higher probable situations happen first
During winterizing I typically jumper zones 2 to 3 zones at a time. Sometimes I go through hot post, Valve test or jumper the zone itself. The inrush doesn't take into a major account because I don't turn on all 3 at once.
There are a lot of factors to include. If you can limit the system to 2 zones that would be ideal. If these zones are next to eachother ( As they should be if you are doubling up) Depending on your pipe sizing and flow rates/ pressure you could physically plumb the zones together instead.
In my opinion the cost of a solenoid with the average solenoid lifespan in comparison to possible site renovations to in order to accommodate ideal circumstances instead of doubling/ tripling zones ( of course is site specific) is probably not worth it. Meaning if you loose out on a couple years from the solenoid for doing this.. Instead of 25 years you get 20 .. Big whoop. It's easy to replace and in all likelihood other issues will happen first.
Solenoid Inrush Measurement
Inrush Current. It is the current required to generate sufficient magnetic force to pull the plunger or overcome the air gap.
If there is any fluid inside the solenoid, the air gap is filled with water which exerts certain amount of pressure on top of the plunger.
We need to know what is the force/pressue exerted on top of the plunger .
F1=P/A
P=water pressure
A= Area of the Plunger where water pressure is exerted.
F1= Force on top of the plunger.
Now the Magnetic force required to pull the plunger is
F= F1+FP
FP= is the weight of the plunger.
Based on the net force which is the required magnetic force use Maxwell force formula:
F = ( Fm)2 μ0 A / (2 g2)
In order to calculate this, you should know the magnetic permeability of the solenoid, material, number of turns in the coil, cross section of the coil ,or the magnet wire Inductance,etc.
The INRUSH does depend on the water pressure and efficiency of the solenoid.
------------------------------
Math aside
I walk into 1000+ systems a year . I often will see a system with MV and 2 zones wired up. Rarely I'll see 3 valves wired into the same port ( no MV)
In my experience in residential- It is very rare that I determine an electrical issue to the controller /fuse has been caused due to additional valves on the same circuit . I have many many more higher probable situations happen first
During winterizing I typically jumper zones 2 to 3 zones at a time. Sometimes I go through hot post, Valve test or jumper the zone itself. The inrush doesn't take into a major account because I don't turn on all 3 at once.
There are a lot of factors to include. If you can limit the system to 2 zones that would be ideal. If these zones are next to eachother ( As they should be if you are doubling up) Depending on your pipe sizing and flow rates/ pressure you could physically plumb the zones together instead.
In my opinion the cost of a solenoid with the average solenoid lifespan in comparison to possible site renovations to in order to accommodate ideal circumstances instead of doubling/ tripling zones ( of course is site specific) is probably not worth it. Meaning if you loose out on a couple years from the solenoid for doing this.. Instead of 25 years you get 20 .. Big whoop. It's easy to replace and in all likelihood other issues will happen first.
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I agree with 99% of what Ron Wolfarth said with the exception of this for Hunter controllers:
Our triacs (station output transistors) do have a safe load limit and if you get into any legal (fire) issues, the manufacturer's recommended spec will be brought into the conversation. This is usually stated in the catalog or online specs. While you might get 3 valves to pop on one terminal, that triac is getting hammered. The Hunter rule of thumb is (max) 2 valves per station output.
When you get into the Big Boy controllers you can "Overlap" multiple programs. For instance, on an ACC conventional, you can run 2 valves per station and 6 simultaneous programs. That's 12 stations at once plus 2 Master Valves.
Obviously an ACC is a little expensive for the purpose first stated in this thread, but you get the point. An I-Core can run 2 valves/station and 2 simultaneous (overlapping) programs, plus a master valve. The new ICC2 can do the same at even less cost. Yes, ICC is back.
Jim made a good point earlier regarding Golf controllers. They have mega-triacs built for multi-valve-in-head operation. The point is that Hunter residential and light commercial solid state controllers do have triac limitations for safety and longevity.
Our triacs (station output transistors) do have a safe load limit and if you get into any legal (fire) issues, the manufacturer's recommended spec will be brought into the conversation. This is usually stated in the catalog or online specs. While you might get 3 valves to pop on one terminal, that triac is getting hammered. The Hunter rule of thumb is (max) 2 valves per station output.
When you get into the Big Boy controllers you can "Overlap" multiple programs. For instance, on an ACC conventional, you can run 2 valves per station and 6 simultaneous programs. That's 12 stations at once plus 2 Master Valves.
Obviously an ACC is a little expensive for the purpose first stated in this thread, but you get the point. An I-Core can run 2 valves/station and 2 simultaneous (overlapping) programs, plus a master valve. The new ICC2 can do the same at even less cost. Yes, ICC is back.
Jim made a good point earlier regarding Golf controllers. They have mega-triacs built for multi-valve-in-head operation. The point is that Hunter residential and light commercial solid state controllers do have triac limitations for safety and longevity.
This is what I originally said though not in as a sexy way HTG put it. Some controllers can run multiple valves some not.
I guess that's why I never get any......respect.
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A one amp, or more accurately, a 20-25 VA rated 24VAC transformer is never going to hammer a 4-amp triac. Even if the output were to be a dead short, the triac would shrug off the current load, and the supply transformer (Class 2 Control Transformer) would cease operation by way of its internal fuse.
I believe the real story is that the design of the "electronic circuit breaker" isn't capable of allowing a safe surge current to pass through the controller.
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Damn, my original post mustve got lost in cyber-ether.
I'm using ESP-LXME for running about 3 valves at the same time. Somebody asked why, because each zone for my smallish yard is tailored to very specific conditions: shade/sun, grass/shrubs, drip
So i have 7 zones but half of are <5GPM hunter MP rotator zones.
A1: Maxipaw rotors: 14GPM
A2: MP Rotators: 1.5GPM
B1: MP Rotators: 4.8GPM bridged with B2
B2: MP Rotators: 2.9GPM bridged with B1
C1: Maxipaw rotors: 14GPM
C2: Maxipaw rotors: 9.5GPM
C3: MP Rotators: 3.2GPM
since they all deliver basically .42 in/h, for simplicity here I have them set at 30 minutes.
Had to spread wires across two 8 zone modules, due to 2 stations/module active limit (strange IMO but clearly some limit on the circuit lines entering the modules)
Using the FloManager function on the ESP-LXME, and inputting my pump's GPM of 27 GPM (actually higher), and 3 valves, spread across two modules: it runs:
A1,A2,C2
then
C1,B1&B2,C3
My system is basically done in one hour instead of 30min x 7zones = 210 minutes = 3.5 hours
I'm using ESP-LXME for running about 3 valves at the same time. Somebody asked why, because each zone for my smallish yard is tailored to very specific conditions: shade/sun, grass/shrubs, drip
So i have 7 zones but half of are <5GPM hunter MP rotator zones.
A1: Maxipaw rotors: 14GPM
A2: MP Rotators: 1.5GPM
B1: MP Rotators: 4.8GPM bridged with B2
B2: MP Rotators: 2.9GPM bridged with B1
C1: Maxipaw rotors: 14GPM
C2: Maxipaw rotors: 9.5GPM
C3: MP Rotators: 3.2GPM
since they all deliver basically .42 in/h, for simplicity here I have them set at 30 minutes.
Had to spread wires across two 8 zone modules, due to 2 stations/module active limit (strange IMO but clearly some limit on the circuit lines entering the modules)
Using the FloManager function on the ESP-LXME, and inputting my pump's GPM of 27 GPM (actually higher), and 3 valves, spread across two modules: it runs:
A1,A2,C2
then
C1,B1&B2,C3
My system is basically done in one hour instead of 30min x 7zones = 210 minutes = 3.5 hours
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Wow! Using the modern heads! :clapping:
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The explanation given to me by Hunter and Rainbird Tech Support was that there was a limiting circuit in the controllers. One could pull in 2 valves and a MV/PSR but that was it, and if you had a magnetic starter for your pump you were dead in the water.
For years we had to use an ice-cube relay wired to a transformer to get enough amperage to pull in multiple valves and pumpstarts/master valves. Then Hunter FINALLY started to actually produce the beast, calling it the PSRB (Pump Start Relay Booster). This had to be used on ALL Hunter controllers, even the ACC/ICC conventionals, and ALL Rainbird controllers.
Somewhere I have that wiring diagram...
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Maybe the current-limiting could be twice applied. One limiter for pump/master valve and one limiter for zone valves. That would probably not strain a modern supply transformer, or if it might, splurge on a 30 VA transformer instead of the 20 VA cheapies that replaced the 40 VA transformers of the olden days.
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I'm a sucker for the impacts. Although these Chinese made Maxipaws pale in quality to the Mexico built ones a decade ago.
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ESP-40MC (output 26.5 vac & 3 Amp)
ESP-ME (output 25.5 vac & 1 Amp)
Depends on solenoid condition. If you are running 2 valves + MV you should be OK. Personally I don't like the low Amps on newer controllers-I wish they would up it to 2 Amps.
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Just curious-how did your preference for impacts heads come up in this "operating multiple zones" arena?
But back to your statement-impacts do indeed have their place today especially for dirty water apps. One of my HOAs was installed (not by me) using Maxipaws in the early 1980s. There were 1700 of them-40 plus to a zone with 5 meter pits and controllers. In the wee hours of any irrigation event there would be 200 of the beasts chattering away-a cacophony that would wake the dead going on for hours. After estimating their needs the HOA board authorized me to do the replacement of 425 per year in their budget. I spent the past four years swapping out those buggers for the RB 5004 PRS.
I also replaced the controllers (Old RCs) with Irritrol RDs with Climate Logic this Spring after removing the remaining Maxipaws. The result was a drastic reduction in noise and approximately a 35% water reduction. The summer quarter water bill went from $48,000 to $32,500. The two quarters (Spring and Fall) EACH went from $35,000 to $22,000. The improvements cost them $91,000. They ROR is slightly more than two years. Win Win.
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A poster joked about using modern heads :laughing:
Put those on Ebay, people seem to always be looking for the used maxipaw's of the 80s/90s with the square-ish reversing trip lever on the back.
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