Connecting Motorsaver 520CP Relay to Controller

My property has the following set up that I am trying to replace the Intermatic timer (manual disc dial) with a controller. Thanks in advance for any expert suggestions you could guide me with.

Symcom Motor Saver 520CP relay switch (Current set up is “normally open”)
Telemecanique Contactor LC1D1810 – 480 V T6 60hz
Intermatic Timer – T101R3
Selector switch that has “Hand / Off / Auto” and the knob is set to Auto

Timer is connected to the switch and contactor and the Motor Saver 520CP relay through spaghetti wiring. I am trying to understand how I may replace the timer with a controller. Thank you.

@rsvenkat - without pictures of the selector switch and the rest of the setup, this sounds like an indexing valve solution.

see ->

One can replace the Intermatic Timer with a Rachio, but one can’t use the Flexible Daily schedule unless the indexing valve is replaced with individual valves as the system will get out of sync. If the Intermatic Timer is located outdoors, then the external enclosure will be needed for the Rachio. Also, the Rachio will use a normal 120 V plug for power and not be directly connected like the Intermatic (unless one is using the external enclosure which needs a direct connect to supply the interior plug).

There are several posts with pictures where others have replace their indexing valve setup with individual valves in a manifold setup.

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Thank you for your swift response. I have uploaded a video of the set up. Please see if this is helpful

We have individual ball valves (not indexing valve) as you may refer in the picture

@rsvenkat - The video was helpful. I believe the control voltage on the Symcom Motor Saver is not 24 VAC but, 120 VAC or higher. Therefore, one would need a pump start relay to provide the appropriate power for the control voltage. The Rachio would send 24 VAC to the pump start relay that would then provide 120 or 240 (not sure what model is in use) to the Symcom Motor Saver.

So I think it would work, but I’m not sure of the advantage one is looking for by replacing the Intermatic. The Intermatic that is dumb and KISS. Yes, the Rachio could provide wind, rain and saturation skips along with messaging when it is running and remote control and seasonal adjustments of the schedule.

Is there just one zone that is being watered? Or are the ball valves changed regularly.

I’d probably recommend getting an electrician to do the connections to the Symcom, unless one is very familiar and comfortable with high voltage wiring.

Short answer - yes, but an additional component - pump start relay - will be needed too.

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Very helpful response DLane. THANK YOU. I will consider adding another pump start relay with 24 VAC to provide the appropriate power for the control voltage. My plan is to replace the manual timer with Rachio controller and replace the manual ball valve with solenoid valves so that I have more control over the irrigation process.

Question: Is there a documentation or link you could share with me that shows how an additional 24 VAC Relay can be connected to my existing 120 VAC relay so that I don’t have to touch any of the existing design than just add an additional relay?

Again a million thanks to your swift responses. It was super helpful.

@rsvenkat - One would get a pump start relay like this ->

The Rachio M terminal and C terminal would be connected to the 24VAC lines on the pump start relay.

The power for the Symcom Motor Saver control line would be on the L1 In and L2 In lines. The normally open control lines going to the Symcom Motor Saver would be on the L1 Out and L2 Out lines.

I’m not a licensed electrician, nor do I work for Rachio, so YMMV. This is my best guess.

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I am all set. THANK YOU DLane. I wish you the very best.