240V 30amp Mechanical Relays

[jlmcgrath]

Hey everyone,

In the gathering stages of putting a control panel together. Very similar to the Electric Brewery setup, but using a gas boil and no volt/amp meters.

I am having a really hard time finding panel mount 240v 30amp mechanical relays for the element switching. I see lots of people using Clion relays but can't seem to find any without having to order 200 of them, or paying $45 each for shipping.

Do I suck that badly at using google?

Anyone have any tips?

Cheers,

Jeff

 

[dave81]

Why do you need mechanical ones? I use solid state relays as do many people.such as this and it is controlled by my pid
http://m.ebay.com.au/itm/231296063774?nav=SEARCH

 

[jlmcgrath]

I have SSR's to switch the elements on and off when the PID wants them to. I am looking for mechanical relays so I can use a switch to turn the elements off is I need to.

 

[dave81]

Just put a switch inline with the ssr trigger

 

[krausenhaus]

This is what I have:

http://www.jaycar.com.au/Electromechanical-Components/Relays-%26-Accessories/Panel-Mount/240V-AC-Panel-Mount-Relay/p/SY4044

You don't need the big cube things that TEB uses.

I use it because I have a switch and indicator light that are rated for 10A while my element is 15A, so I can't have them in series with the element.

 

[mofox1]

Try looking for larger current switching relays... I ended up with 80A relays as they were available and reasonably priced.

First hit on aliexpress for me was us$28 for two, free postage. Searched for "80a relay" although often it helps to add the word coil.

No linky sorry, on phone. There was another one there for us$18 ea.

 

[n87]

http://au.element14.com/webapp/wcs/stores/servlet/Search?catalogId=15001&langId=43&storeId=10184&categoryId=800000004761&pageSize=25&showResults=true&pf=111783444,111783449,111783467,111783468,111783469,111783471,111783478,111783482,111783483,111783489,111783568,111783571,111783572,111783576,111783577

http://www.jaycar.com.au/Electromechanical-Components/Relays-%26-Accessories/Panel-Mount/24VDC-Panel-Mount-Relay/p/SY4041


i like the clicks of a mechanical relay

 

[mofox1]

http://au.element14.com/webapp/wcs/stores/servlet/Search?catalogId=15001&langId=43&storeId=10184&categoryId=800000004761&pageSize=25&showResults=true&pf=111783444,111783449,111783467,111783468,111783469,111783471,111783478,111783482,111783483,111783489,111783568,111783571,111783572,111783576,111783577

http://www.jaycar.com.au/Electromechanical-Components/Relays-%26-Accessories/Panel-Mount/24VDC-Panel-Mount-Relay/p/SY4041


i like the clicks of a mechanical relay

The big ones go clunk.

 

[Eagleburger]

Could use a low volt switch on the control side of the ssr.

 

[dblunn]

If you are wanting to have electrical isolation then I would stick to the relay/switch on the downstream side of the SSR. Those SSR devices are more fragile than a relay and could fail at an inopportune time, even when working normally they have a small leakage current that may cause safety concerns.
Dave

 

[jlmcgrath]

Wow! The difference in returned search results between 80 amp relay and 80a relay is crazy. Thanks for helping to learn the internets.

Just to confirm my thoughts really quickly. I will have 2 feeds to my control panel. One 10A and the other 15A. 10A runs the HLT, 15A runs herms, electronics and pumps.

Control panel will have a master key switch. I would use 1 x DPDT relay for the incoming feeds, and a SPST for each of the elements?

Thanks again everyone.

Jeff

 

[jonnir]

Throw some links up of the gear that your finding mate, may be able to help better

 

[dave81]

Would you need 2 dpdt for the feeds,1 for each? or instead of isolating the neutral aswell are you just going to use 1 leg for each active supply?

 

[jlmcgrath]

Thanks for posting that Dave, it all just clicked. So I would need 4 DPDT total.

 

[Camo6]

Like Dave81 says you'd be better to use DPDT to isolate A&N to the elements. My main relay only isolates the active in but I would use DPDT's if I had to do it again.

 

[Eagleburger]

I use ptp for isolation. Pull the plug.

 

[MitchD]

So many experts so little good advice.

 

[krausenhaus]

So many experts so little good advice.

You're an electrician, right? If you see bad electrical advice being given to a forum member then maybe you can chime in and contribute to someone's safety instead of just dropping a smug comment and moving on.

 

[MitchD]

Perhaps all the non electricians could stop offering poor advice.

The op hasnt posted any plans so I dont know what he plans to control and how. But I would never be wiring the neutral through a contactor.

 

[dblunn]

But I would never be wiring the neutral through a contactor.

Normally yes but, as the final point of isolation before the element of a portable water heater that may well be supplied via an extension lead, I think a double pole switch/relay would be a good idea.
Dave