Dry Contact controlled power source for water pump

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seoras

90 posts

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#229222 13-Feb-2018 16:40

I've got a UV system for killing bugs in a water system. Works fine. Just no one hears the alarm when it goes off.

The controller of the UV does have Dry Contacts (COM,NC,NO) for other options, ie solenoid, bigger/remote alarm, lights etc

I've got a bit of a electronics background but I'm no electrician.

Can someone recommend product(s) that can use the dry contacts switch to turn off the power to the pump?

Googling around doesn't really turn up much of any use other than marine products or other lower powered relays.

Thanks!

Aredwood

3885 posts

Uber Geek

#1956458 13-Feb-2018 16:57

What is the power rating of the contacts? Assuming they can safely handle mains voltages and the pump motor current. Just wire the incoming mains to COM and the NC contact to the motor.

If the contacts can switch mains, but only a small current. Then wire in a contactor to switch the power to the motor.

As always if you are unsure about anything to do with mains power. Get an electrician in to sort it out. It should be an easy job for them. No specialist parts are needed for what you want to do.

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seoras

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#1956461 13-Feb-2018 17:02

Aredwood: What is the power rating of the contacts? Assuming they can safely handle mains voltages and the pump motor current. Just wire the incoming mains to COM and the NC contact to the motor.

If the contacts can switch mains, but only a small current. Then wire in a contactor to switch the power to the motor.

As always if you are unsure about anything to do with mains power. Get an electrician in to sort it out. It should be an easy job for them. No specialist parts are needed for what you want to do.

Nope. Needs to be relayed. The relay contacts are rated for 2A and 250 VAC. The pump max's out at 16A.

Aredwood

3885 posts

Uber Geek

#1956475 13-Feb-2018 17:16

Like I said, get a contactor (relay that accepts mains voltage on its coil).

I assume that you know how to wire up a relay. If not then you definitely need a sparky.

seoras

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#1956501 13-Feb-2018 18:48

Aredwood: Like I said, get a contactor (relay that accepts mains voltage on its coil).

I assume that you know how to wire up a relay. If not then you definitely need a sparky.

Like I asked, can someone recommend product(s) that can use the dry contacts switch to turn off the power to the pump?

You've given me terminology in "contactor".

Can someone give me an example product matching the specs I've detailed.

sparkz25

750 posts

Ultimate Geek
Inactive user

#1956502 13-Feb-2018 18:53

use a hager din mounted contactor as the contacts in the hager are ususally 20-25a and would work fine then you just need to interface it to the alarm contacts on the uv filter

seoras

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#1956507 13-Feb-2018 19:02

sparkz25:

use a hager din mounted contactor as the contacts in the hager are ususally 20-25a and would work fine then you just need to interface it to the alarm contacts on the uv filter

Is there nothing other than DIN mounted on the market for this sort of application? I did see a few in my searching but it seemed like an over kill.

Volt

38 posts

Geek

#1956509 13-Feb-2018 19:20

seoras:

sparkz25:

use a hager din mounted contactor as the contacts in the hager are ususally 20-25a and would work fine then you just need to interface it to the alarm contacts on the uv filter

Is there nothing other than DIN mounted on the market for this sort of application? I did see a few in my searching but it seemed like an over kill.

By memory the Omron G7L series is rated to 25A with a choice of coil voltages, they are not rail mounted and have a few form factors

andrewNZ

2487 posts

Uber Geek
Inactive user

#1956556 13-Feb-2018 19:47

I'd avoid stopping the pump, I can think of a lot of things that could go wrong if the water just stopped. What if you're: in the shower or cooling a burn.

What about using the contacts to turn on a lamp and/or loud alarm.

seoras

90 posts

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#1956572 13-Feb-2018 20:06

andrewNZ: I'd avoid stopping the pump, I can think of a lot of things that could go wrong if the water just stopped. What if you're: in the shower or cooling a burn.

What about using the contacts to turn on a lamp and/or loud alarm.

Not in this case. I'm not going into details of who/where/why. Suffice to say that the system needs to be flushed with chlorine when the UV fails and/or E.Coli is detected in the water supply. It's tested monthly. There is no shower. Aloe vera works better for burns.

Perhaps this is why I've found little in my research on taking this approach. The domestic pumps on the market don't seem to offer an off trip from the UV controller which would be the sensible way of doing it as they already contain pressure off relays.

sparkz25

750 posts

Ultimate Geek
Inactive user

#1956637 13-Feb-2018 21:29

seoras:

andrewNZ: I'd avoid stopping the pump, I can think of a lot of things that could go wrong if the water just stopped. What if you're: in the shower or cooling a burn.

What about using the contacts to turn on a lamp and/or loud alarm.

Not in this case. I'm not going into details of who/where/why. Suffice to say that the system needs to be flushed with chlorine when the UV fails and/or E.Coli is detected in the water supply. It's tested monthly. There is no shower. Aloe vera works better for burns.

Perhaps this is why I've found little in my research on taking this approach. The domestic pumps on the market don't seem to offer an off trip from the UV controller which would be the sensible way of doing it as they already contain pressure off relays.

It will be why you cant find information on the setup as it may not have been done before or just hasn't been documented.

The domestic pumps dont and will not offer a external trip ever as they have a molded plug top fitted to them and are mainly designed to be plugged in only.

Can you get a pic of the external alarm contacts for this filter?

Is your pump plug in, or is it hard wired?

Volt:

seoras:

sparkz25:

use a hager din mounted contactor as the contacts in the hager are ususally 20-25a and would work fine then you just need to interface it to the alarm contacts on the uv filter

Is there nothing other than DIN mounted on the market for this sort of application? I did see a few in my searching but it seemed like an over kill.

By memory the Omron G7L series is rated to 25A with a choice of coil voltages, they are not rail mounted and have a few form factors

as Volt mentions here the omron g7l is a good choice but you will still need to put it in a enclosure to protect the relay and prevent human contact with it
i have a drawer full of contactors and things that would work that have terminals or are din mount, but they all still need to be in a enclosed box.

and i would even make sure its a IP56 enclosure if its in a wet area

seoras

90 posts

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#1956679 13-Feb-2018 23:31

sparkz25:

seoras:

andrewNZ: I'd avoid stopping the pump, I can think of a lot of things that could go wrong if the water just stopped. What if you're: in the shower or cooling a burn.

What about using the contacts to turn on a lamp and/or loud alarm.

Not in this case. I'm not going into details of who/where/why. Suffice to say that the system needs to be flushed with chlorine when the UV fails and/or E.Coli is detected in the water supply. It's tested monthly. There is no shower. Aloe vera works better for burns.

Perhaps this is why I've found little in my research on taking this approach. The domestic pumps on the market don't seem to offer an off trip from the UV controller which would be the sensible way of doing it as they already contain pressure off relays.

It will be why you cant find information on the setup as it may not have been done before or just hasn't been documented.

The domestic pumps dont and will not offer a external trip ever as they have a molded plug top fitted to them and are mainly designed to be plugged in only.

Can you get a pic of the external alarm contacts for this filter?

Is your pump plug in, or is it hard wired?

Volt:

seoras:

sparkz25:

use a hager din mounted contactor as the contacts in the hager are ususally 20-25a and would work fine then you just need to interface it to the alarm contacts on the uv filter

Is there nothing other than DIN mounted on the market for this sort of application? I did see a few in my searching but it seemed like an over kill.

By memory the Omron G7L series is rated to 25A with a choice of coil voltages, they are not rail mounted and have a few form factors

as Volt mentions here the omron g7l is a good choice but you will still need to put it in a enclosure to protect the relay and prevent human contact with it
i have a drawer full of contactors and things that would work that have terminals or are din mount, but they all still need to be in a enclosed box.

and i would even make sure its a IP56 enclosure if its in a wet area

Pump is plug in. I had originally hoped I could find a plug in adaptor on the market since there are plenty of plug in timer switch and smart home adaptors (WiFi).

Don't have a photo of the Dry Connector.

Aredwood

3885 posts

Uber Geek

#1956692 14-Feb-2018 01:08

seoras:

Pump is plug in. I had originally hoped I could find a plug in adaptor on the market since there are plenty of plug in timer switch and smart home adaptors (WiFi).

Don't have a photo of the Dry Connector.

Zero point in a company making such a device. As it would need to contain a low voltage isolated power supply, to be sent to the dry contacts. As you definitely can't sell a plug in device to consumers, that has bare wires on it that are connected directly to mains power, that they are then expected to figure out how to wire themselves. And if such wires are extra low voltage only - people will still figure out plenty of ways to destroy such devices.

Plug in timers and wifi smart home adaptors also don't require consumers to do their own wiring, so not a valid comparison.

And pump controllers won't have any external input connectors. As that complicates lots of things such as the power supply design. Unless you go to high end pump controllers that cost big $$$ to buy.

Why not just ask the company that sold you the UV lamp system, if they have a supported solution for what you want.

But the main reason why it is not documented anywhere, is that what you want to do is very basic to an electrician. It is no different to someone asking an electrician to wire up a light switch in a handy location, to control a motor, where the motor draws more power than what the switch is rated to.

And

seoras:

I've got a bit of a electronics background

Implies that you understand what relays / contactors are, and how to wire them. And that you are happy to do wiring work yourself. As you would have to connect some wires to the dry contacts no matter what. Even if those wires are only extra low voltage.

Sorry if this sounds a bit blunt. But please, more detail the better. As I thought that the reason you couldn't find what you needed, was just due to not knowing the right terminology. (which is why I told you to get a contactor).

seoras

90 posts

Master Geek

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#1956712 14-Feb-2018 07:45

Aredwood:

seoras:

Pump is plug in. I had originally hoped I could find a plug in adaptor on the market since there are plenty of plug in timer switch and smart home adaptors (WiFi).

Don't have a photo of the Dry Connector.

Zero point in a company making such a device. As it would need to contain a low voltage isolated power supply, to be sent to the dry contacts. As you definitely can't sell a plug in device to consumers, that has bare wires on it that are connected directly to mains power, that they are then expected to figure out how to wire themselves. And if such wires are extra low voltage only - people will still figure out plenty of ways to destroy such devices.

Plug in timers and wifi smart home adaptors also don't require consumers to do their own wiring, so not a valid comparison.

And pump controllers won't have any external input connectors. As that complicates lots of things such as the power supply design. Unless you go to high end pump controllers that cost big $$$ to buy.

Why not just ask the company that sold you the UV lamp system, if they have a supported solution for what you want.

But the main reason why it is not documented anywhere, is that what you want to do is very basic to an electrician. It is no different to someone asking an electrician to wire up a light switch in a handy location, to control a motor, where the motor draws more power than what the switch is rated to.

And

seoras:

I've got a bit of a electronics background

Implies that you understand what relays / contactors are, and how to wire them. And that you are happy to do wiring work yourself. As you would have to connect some wires to the dry contacts no matter what. Even if those wires are only extra low voltage.

Sorry if this sounds a bit blunt. But please, more detail the better. As I thought that the reason you couldn't find what you needed, was just due to not knowing the right terminology. (which is why I told you to get a contactor).

Who said I was looking for a wired solution? OK, let me be blunt too. You make a lot of (incorrect) assumptions and have yet to make any contribution of value to this conversation. If you have nothing of value to add then, I'm sorry, but I'm not interested in starting an ego fight with you.

I want to be informed before I engage a tradesman for something that's not a bog standard job. Since tradesmen are paid by the hour I don't expect whoever I get to do too much homework on whats available on the market. If, in the unlikely scenario, there was such a consumer installable solution I wouldn't want to miss it either.

So, and this goes for anyone else who wants to reply here, read what I've asked, stick to the facts and only answer if you've got a product to suggest.

I've had 2 good ones so far from sparkz25 & andrewNZ. Thanks guys.