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wiring a relay for a pump timer

real ting

Member
I have a question for the electricians out there. I have this recycling timer: http://www.amazon.com/C-A-P-ART-DNe-Adjustable-Cycle-Timer/dp/B00286QNDM?tag=duckduckgo-d-20

And I'd like to set it up so that it's switching a relay which then turns the pump (a danner mag drive 950) on or off. I've wired up flip flops before, so I know pretty much how to go about wiring it, but I don't know what kind or voltage of relay would work best.

I know that I can plug the pump directly into the timer, but I have read several reports of bad reliability (having them stop switching at after a year or so, which could flood the room) on these art-dne units when used that way, and I think a relay may help with that problem.

Is something like this DPST 120v relay what I should be looking at? http://www.grainger.com/Grainger/DAYTON-Power-Relay-5Z546?Pid=search

Or is there another part that would work better? It would be awesome if you can find something that's available in the grainger catalog.
 

Avenger

Well-known member
Veteran
that relay will work, but it is a bit overkill on the amperage duty if all you are running is a pump. Also you really only need spst if your pump operate on 120 volts.
 
I'd stick to the timer. That relay's coil is 120v and your load is 120v. Relays/Contactors are practical for using extra low voltage (24V for example) and switching 120,240,347,600V. This might not be the best idea to go about with your problem. Just a suggestion.
 

delta9nxs

No Jive Productions
Veteran
hey, i looked at your link on the cap timer and it is only rated for 5 amps. i didn't know that as both my green air and the sentinel are rated for 15, which will fire huge pumps no problem. if you already have the cap i think the relay is a good idea and the one you have shown will work fine. it is normally open so a failure of either the timer or the relay will not fire the pump.

later
 

rives

Inveterate Tinkerer
Mentor
ICMag Donor
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As mentioned, that relay will work fine but is far heavier-duty than you need for this application. If you are going to put together a light controller or flip, it would work very well for that and you could minimize your spare parts inventory by using it. The below relay and base is a little more suited to this application. You might want to check out Automation Direct.com for parts - they are very reasonable, free 2-day shipping over $49, etc.

http://www.grainger.com/Grainger/OM...cm_sp=IO-_-IDP-_-RR_VTV70300505&cm_vc=IDPRRZ1

http://www.grainger.com/Grainger/OMRON-Relay-Socket-For-Double-Pole-Double-4DG59

I'd stick to the timer. That relay's coil is 120v and your load is 120v. Relays/Contactors are practical for using extra low voltage (24V for example) and switching 120,240,347,600V. This might not be the best idea to go about with your problem. Just a suggestion.

D&C, relays are usually used in order to increase the current (amperage) capacity of the contacts. Most contacts in devices can usually handle a wide range of voltage with no problem.
 

real ting

Member
got me considering this now. How do those things wire up. I don't know anything about them. does relay wire to pump, timer, or outlet? do you need any special wiring? that would really suck if pump never shut off and flooded.

If you have to open the CAP timer up im assuming it will void the 3 year warranty on it?

Also, would this relay be better? http://www.grainger.com/Grainger/DA...cm_sp=IO-_-IDP-_-RR_VTV70300505&cm_vc=IDPRRZ1
That's a good question. You shouldn't have to open up the timer.

Here's how I believe it should work(If I'm wrong I would very much like to be corrected!), I stole this image from the dopest's diy flip flop tutorial, here

https://www.icmag.com/gallery/data/500/7541relaywire.jpg

Imagine instead of 4 contacts on the outgoing side of the relay, there's just 2. The hot and neutral incoming from a power cord plugged into a wall socket on one side, and the hot and neutral outgoing to the pump power cord on the other. The hot and neutral coming from a cord plugged into the cap timer(which is plugged directly into a wall socket) are wired into (5 and 6) on either side of the relay. And then you also need to tie the grounds together and to a ground screw in the metal box you're using.

Basically when the cap timer switches to ON, it closes the relay, delivering power to the pump. When the timer switches to off, it opens, cutting off power to the pump.

Someone mentioned using a SPST relay earlier, I assume in that case you'd just wire the neutrals together for the pump and only switch the hot.
 

real ting

Member
As mentioned, that relay will work fine but is far heavier-duty than you need for this application. If you are going to put together a light controller or flip, it would work very well for that and you could minimize your spare parts inventory by using it. The below relay and base is a little more suited to this application. You might want to check out Automation Direct.com for parts - they are very reasonable, free 2-day shipping over $49, etc.

http://www.grainger.com/Grainger/OM...cm_sp=IO-_-IDP-_-RR_VTV70300505&cm_vc=IDPRRZ1

http://www.grainger.com/Grainger/OMRON-Relay-Socket-For-Double-Pole-Double-4DG59


Thanks man, I will look into it! I think automation direct is where I got the relay for my flip.


hey, i looked at your link on the cap timer and it is only rated for 5 amps. i didn't know that as both my green air and the sentinel are rated for 15, which will fire huge pumps no problem. if you already have the cap i think the relay is a good idea and the one you have shown will work fine. it is normally open so a failure of either the timer or the relay will not fire the pump.

later


I hadn't thought about NC vs NO, that's a very good point! I went ahead and got the CAP since I'm in a bit of a time crunch and it was available quickly. The sentinel drt-1 looks sweet but I couldn't get my hands on one.
 
D&C, relays are usually used in order to increase the current (amperage) capacity of the contacts. Most contacts in devices can usually handle a wide range of voltage with no problem.

I understand devices can be rated for different voltages / amperage. Relays are usually used to increase current capacity? If the timer is known to be faulty then get a more reliable one.

Pump on N.o contacts, coil is energized and pump runs.
-If timer is faulty and shorts, breaker trips. (No flooding)
-If timer is faulty and it's putting out zero voltage, pump wont run (No flooding)
-If timer is faulty and puts out constant voltage, coil will be energized (Flooding) This is why it's not a good idea.
 

rives

Inveterate Tinkerer
Mentor
ICMag Donor
Veteran
I understand devices can be rated for different voltages / amperage. Relays are usually used to increase current capacity? If the timer is known to be faulty then get a more reliable one.

Pump on N.o contacts, coil is energized and pump runs.
-If timer is faulty and shorts, breaker trips. (No flooding)
-If timer is faulty and it's putting out zero voltage, pump wont run (No flooding)
-If timer is faulty and puts out constant voltage, coil will be energized (Flooding) This is why it's not a good idea.

Many devices have contacts with low amperage capabilities. This only makes them "unreliable" if you exceed the capabilities of the switch. For instance, I am building up a new control system using an Allen Bradley Micro Controller, and each output interfaces to a more robust relay so that I can drive whatever I want without worrying about exceeding the capacity of the internal contacts and potentially ruining the controller because the contacts aren't serviceable.

All that being said, if the device is unreliable, by all means find another one. From what I've seen of CAP's gear, they fail to follow accepted standards regarding code and safety standards, which would lead me to doubt that they are concerned with adhering to proper circuit design standards either.
 
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real ting

Member
All that being said, if the device is unreliable, by all means find another one. From what I've seen of CAP's gear, they fail to follow accepted standards regarding code and safety standards, which would lead me to doubt that they are concerned with adhering to proper circuit design standards either.

I could not find another more reliable device in the time frame I needed it. The timer is for a pump running a ppk setup, it has to be able to have on times in a 30 second to 1 minute range, with fine adjustment, off times of 30 minutes, and repeat that cycle endlessly.
 

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