Electric Panel setup with Cratridge heaters

[CubDenBrewery]

I read through the Panel setup posted here but I'm having troubles applying it to my setup. I have a HERMS setup.

2 240v cartridge heaters, a 4500w in my HLT and a 2000w in my BK.
2 PIDS
2 SSR
2 12v pumps(which I want controlled with potentiometers)

I am ordering switches: a key switch to engage all power, a switch between the elements and pots for the pumps.

My questions so far are: are the mechanical DPDT relays necessary or can the heaters be controlled just using the SSR's? IF they necessary, why?
are the meters(volt and amps) necessary?
What would the wiring setup be?

Any forwarding links or advice would be awesome because I just can't seem to find anything.


For those unfamiliar with cartridge heaters they have 2 wires going into them, two hots. no ground or neutral.

for clarification, the choice for the cartridge heaters were based on their length. the 4500w is too long to put in the BK so thats why it resides in the HLT. I figure if the 2000w takes too long to boil i'll run the wort back through the HERMS at a hotter temp until the 2000w can maintain.

 

[sandyeggoxj]

The meters are just cool bling. They can help you figure out if your elements are working right if you have high or low amp draw but my experience is that you do not need them to brew.

SSRs are notorious for leaking current even when they are off. They can also fail closed leaving you no way to shut off power. That is where the contactors come into play. It allows the operator to shut down power to an element physically.

In terms of wiring the heaters. All heaters have two leads going into them. For 240vac that will be L1 and L2, for 115vac that will be L1 and N. The ground is developed through the metal body that threads into the vessel. That is why you want your panel grounded to the kettles and stand.

You can go through the auberins.com page and look at the switches and whatnot and then go to ebay and amazon and buy them direct from china. It will save you a few bucks on all the goodies.

 

[augiedoggy]

The meters are very useful in knowing for sure if your elements are working or not or if somethings wrong...For me they were an easy way to see how much power I was drawing at any given time since I run everything off one 30a circuit.
A multifunction amp/volt meter costs about $10 shipped when bought on amazon or ebay... I bought a fancy one that actually gives me a wattage readout so I can see what my elements really put out and it was $11 shipped so while its not needed (its more practical than a keyed switch in my opinion) Its not a large expense and it could save you from finding out too late that one of your contactors or ssr's has failed. Indicator lights can do this too but that all depends on how you have it wired and if you wired them to the load or the switching power..

BTW I used the same type of pumps as you and a cartridge heater in my rims (only ULDW) in the build thread in my signature... if you haven't bought the pumps yet I strongly suggest the 24v versions which are about 1/3 stronger than the 12v versions. any reason you are stuck on the idea of using cartridge heaters? they are not practical for this application and for around $20 including shipping you can buy an all stainless element that will be much easier to safely wire up for kettle use and that will actually fit safely. for $27 this would be a better choice and is also sold in 4500w sizes...plus you wont need to spend time and money on insulating your boil kettle so the 2000w element can hold the boil. It would also shave up to an hour off each brew session.

http://www.ebay.com/itm/Aiicioo-Ele...00W-For-Water-Tank-Brewing-Beer-/321930407926 you can drill a hole and use a ground screw to attach the ground wire needed for the gfci and safety reasons if you are commited to the HWD cartridge heaters. (which may likely cause scorching BTW) an ULWD 2000w cartridge heater would be over 24" long...