The valve monitoring documentation is unclear for interpreting results for those with a well pump & PSR setup. I imagine the same would apply to anyone with a master valve setup.
In the iOS app valve monitoring provides a milliamp baseline and also measures every run. I’ve noticed my milliamp draw with a PSR setup is quite high. It would be the same as running 2 valves on 1 zone because it still has to activate a second 24VAC device simultaneously with a zone valve.
I get a variation of about 140ma to 180ma during calibration depending on the time of day. I’m in Florida and it’s summer so heat does play a factor with resistance between the middle of the day or middle of the night. Those who live in higher heat areas like Arizona might get a larger deviation between night and day.
In the documentation I see no Q&A for this type of setup and how it measures the current draw. Does it measure both the PSR and zone valve and combine them (a+b) = ma or does it only measure the zone valve? Because 180ma for 1 zone valve would be concerning but halving that to 90ma is within an acceptable range. Does the PSR require more milliamps than a zone valve so that the equation is unequal? I hope you see what I’m getting at.
My system works fine but that’s not the point. The documentation is unclear how to interpret the results and if/when those reading should become a concern. Since they seem to be combined it might be harder to tell when a valve solenoid is actually out of range.
I think there needs to be a section in the documentation for well/PSR and MV owners on how to interpret the milliamp readings in the valve monitoring portion of the app.
There is a section in the app where you can specify if you have a well pump or master valve setup but the ma report still seems to combine them for a total milliamp instead of halving them. If this is something the Rachio 3 cannot currently do please consider this for a future product idea so those with PSR/MV setups can get accurate reports for both.
I’m not an irrigation tech nor an electrician, but here is some possibly useful information I found in the Rachio community forum and on Reddit:
Rachio’s valve monitoring feature is designed to measure the current draw of the solenoid valves in your irrigation system. When using a well pump start relay (PSR), the monitoring primarily focuses on the current draw of the zone valve solenoids.
In a typical setup, the well pump start relay is triggered by the master valve (or pump) terminal on the Rachio controller. The PSR itself has a very low current draw, as it is merely acting as a switch to turn the well pump on and off. The significant current draw comes from the irrigation valves, not the relay.
When a zone is activated, the Rachio controller sends current to both the PSR (through the master valve terminal) and the specific zone valve. The valve monitoring feature will primarily measure the current draw of the zone valve solenoid. The combined effect of the PSR and zone valve is typically not the focus because the relay’s draw is minimal compared to the solenoid.
The typical current draw for a single irrigation valve solenoid on a Rachio system should be around 200 milliamps (mA). This can vary slightly depending on the specific model of the valve and the age of the solenoid. They’re usually about 5 watts, so 5W / 24V = 0.208A. Some might incorrectly use Ohm’s law to calculate it, (24v / 25ohms = 1A) but solenoids are not resistors, they’re inductors, so inductive reactance needs to be added to the Ohms before calculating.
Based on this information, it seems like 180 mA would be a reasonable reading. Hope that helps! Rachio support feel free to correct anything I said wrong. 
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My valves range from 174-188 with the average about 180. I have a PSR on one zone for a water feature and it draws 222. They all will vary with brand, model, distance, wire gauge, heat, age, etc. My PSR is rated higher than needed and more than what what most need.
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Thank you. That’s exactly the kind of information I was looking for. Thank you both for the example loads too. Very helpful.
When I calibrated it the first day (about a month ago) all of my loads were around 130. Then started getting warnings at 180 that they were too high. Recalibrated again and all are around 175-180 with Hunter PGV valves and Hunter PSR-22.
Why my initial calibration was so low I have no clue. Nothing changed in my system other than perhaps a 10F difference between June and July. Maybe some kind of automated update changed something, no clue. I’m very happy to know my new calibration is more of an expected value.
I love that Rachio has this type of feature and would love to see them progress with more diagnostics by adding wiring distance from controller to valves, wire gauge, separate load reporting for PSR and valves, etc…
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If I remember right, we have the same valves and PSR. That is interesting that yours were so low. I think I could calibrate 10 times and get 10 different answers.
Disconnect the valve or the PSR and turn the zone on - what is the measured mA? It measures impedance, not resistance. Impedance is variable, starts with pure resistance at first then drops due to the coil introducing the inductive resistance. This is also A/C so if the measuring mechanism uses a time window that is not multiple of the wave length, depending on how off the phase is, the value differs slightly. Temperature has very little to do with it - the coil heats up enough to compensate for environmental temperature noise.
My valves range between 150-190mAh and their specs say:
Electrical Specifications
24 VAC 50/60 Hz (cycles per second) solenoid power requirement:
0.30 A (7.2 VA) inrush current; 0.23 A (5.5 VA) holding current
Solenoid coil resistance: 38 Ohms
Specs say 230mAh, so I would venture to say the measurements you see do NOT include the PSR. Although I just realized, there is probably no way to tell what the Master consumes? is that even tracked?
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