Monday, March 10, 2014

220v Timer Switch



I have a lawn irrigation well that has a 220 pump. Currently i use it to water the lawn. The well is turned on/off with a single throw switch mounted in a single box on the side of the house. I would like to be able to turn the well on and have it turn off at a predetermined period of time.
Example: I am leaving home at lunch to go back to work. I sprinklers (not in ground) in the front yard, and i want to start the well, and have them run for 45 minutes and then shut off. I know a sprinkler controller will do this but i want a simpler mech. I would think there would be something like a wound timer etc. that would work but i can't find online.

Have a look at the Intermatic brand timers they sell for controlling pool pumps and other similar loads. There should be something there that meets your need.
Down at the bottom of the left column is a mechanical time switch category with several different types of timers:
Timers | Intermatic, Inc.

The advantage to a wind- down timer is that it's a one-time-only operation , and does not re-cycle and operate again at an inopprotune time.
Because you are controlling a 220 volt circuit, this type of timer is best used in this application to control a 2-pole contactor or switching-relay . You don't want the timer contacts inserted in a 220 volt power .circuit.

I gave some incorrect information earlier. Upon further inspection my current switch is a Leviton 115 V. Apparently i already have a relay????
http://www.farm-home.com/mn/v11_cata...51-0857~~~~~~~

Any other ideas on how i can install a 110v 15 amp spring wound timer switch outside into an existing surface mounted single gang box?

Sure, you can find them here Let me google that for you

If the motor has a different maintenance disconnect means such as a cord or a pullout switch, it is legal to just replace your toggle switch with the spring wound timer and wire it to only break one of the hots.
The code requires that motors have a disconnect which switches off both hots, but additional timers, controllers, etc are allowed to just switch one hot.
You could surface mount another single gang box right next to the current one joined by a short conduit nipple. Leave the current disconnect switch, but run one of the hots through the wound timer in the adjacent box so that both the switch and the timer must be on for the pump to run.

Here is a pic. You can see the toggle switch and the box it goes to.

If you mount the Wind-Down timer on the box , the problem is to have the knob in a weather-tight enclosure ; to do this , set a 1 deep weather-proof extension box on the existing box after the timer is in place, then set a weather-proof plate with a vertical hinge-door cover on the extension box.

Originally Posted by wirenut1110
Sure, you can find them here Let me google that for you
Thanks.
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If the breaker for the pump is in one of those boxes pictures above or beside, then you can simply replace the current switch with the spring timer. The breaker (within line of sight) would count as the maintenance disconnect means. I recommend an in-use bubble cover over the timer.
You could use either a DPST timer and break both hot legs or a SPST timer and break one leg.

Originally Posted by ibpooks
If the breaker for the pump is in one of those boxes pictures above or beside, then you can simply replace the current switch with the spring timer. The breaker (within line of sight) would count as the maintenance disconnect means. I recommend an in-use bubble cover over the timer.
You could use either a DPST timer and break both hot legs or a SPST timer and break one leg.
The box above it is the pump motor control box.

What is the difference between the motor control box and a pump start relay which I will need if i decide to go with sprinklers?
Will the pump start relay replace the motor control box?






Tags: timer, switch, timer break, wound timer, current switch, disconnect means, maintenance disconnect, maintenance disconnect means, motor control, switch with, switch with spring