SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

You can't assume, you've got to look at the specifications for your equipment.

And I must admit, I don't know where Hunter is getting its information on the controller being able to support the equivalent output of three valves at one time. If you look at their numbers closely, three Hunter HPV valves technically goes over their own specifications.

The Hunter HPV:
0.37 amps in-rush current (current required to open a valve) and a holding current of 0.19 amps
0.19 amps holding current (current required to keep the valve open)

I then looked up the specification on the Pro-C:
0.56 amps per zone (I assume that is holding current since 0.19x3=0.57 amps, 0.01 amps above the per zone spec)
0.28 amps on the pump relay connection
1.0 amps Transformer capacity.

So for starters, if the control already has a pump relay connection, why not use it. I would imaging the controller is designed to first start the pump and give it a little bit of time to build up pressure before turning any of the valve on. If so, it would seem that connecting your pump to the connection designed for it would be best.

But if you are not... well I can only ASSUME the 'master' zone has the same 0.56 amp capacity of the other zones (it's not listed separately in the specifications). That would seem to indicate that if you are using a Hunter valve for your master valve, then you've got 0.37 amps left over for a pump relay.

However, keep in mind that it says the transformer has an output of 1.0 amps. That means the current of the pump relay, the master valve, and the zone valves on a single zone can not total more than 1.0 amps. (Perhaps even less since you need to account for some current running the controller).

But once again, Hunter is a little shy on the specs, but apparently you can go over the specs, at least a little, because their own marketing material does.

Quoted from "mollye"

Just in the process of ordering a controller. I have a well and I'm looking at the Hunter Pro-c. My question......I'm going to hook up my pump starter low voltage wires and my master valve low voltage to the same terminal. Will that work? Does that termainal have enough capacity. The nomenclature on the power module reads PR/Master.. implying one or the other or.... is that Both? All thee other station terminals can run up to 3 zone valves? Should work ...right? I'm using hunter zone valves and have checked the current draw on them and a hunter master valve along with a Hunter PR 22 Starter relay.

You don't directly connect a pump to a sprinkler controller. You connect a pump relay to the pump/master-valve terminal of the controller, and then the pump relay connects to the pump. If this pump operates only when the sprinklers are on, then a master valve might be redundant.

Quoted from "mollye"

...The nomenclature on the power module reads PR/Master.. implying one or the other or...

I did not pay close enough attention to this part of the initial post. When I looked up the specs for the Hunter Pro-C, something in the specs made it sound like there was perhaps a terminal for a Master Valve AND as SEPERATE Pump Relay terminal.

But if there is only one terminal for both, then the specifications appear to indicate that the total current draw on that terminal is 0.28 amps. So if you are going to have a Pump Relay AND a master valve, the two of them together can not draw more than 0.28 amps. So based on the spec of 0.19 amps, that would only leave 0.09 amps left for a pump relay... so that sounds like the terminal does NOT have the capacity for both a Pump Relay AND a Master Valve.