Wire gauge question

[guillaume]

I've been looking around the internet for a few weeks now and I'm so close to buy all the parts to switch to electric brewing. It's mainly to save on propane (more for cooking in summer) and I'll be able to brew in winter too...

I'm still living in an appartment so I can't switch out breaker in the panel (well I could, but I don't want to take that risk). I have easy access to my stove outlet (NEMA 14-50) which is on a 40A breaker in the panel.

I want to use a 50A gfci spa panel (found one used for 70$ instead of 200$ here in Canada...). Can I use it since it's higher than the 40A? I'm guessing the answer is yes.

I'll use 1 5500w camco element which would need 23A at most on 240V. I could always use a 4500w element instead for lower amp. Do I need to use 8 gauge wire since it's on 40A breaker or since I'll only use 23A I can go with 10? I'm guessing yes again (or hoping it is).

 

[RichBenn]

I've been looking around the internet for a few weeks now and I'm so close to buy all the parts to switch to electric brewing. It's mainly to save on propane (more for cooking in summer) and I'll be able to brew in winter too...

I'm still living in an appartment so I can't switch out breaker in the panel (well I could, but I don't want to take that risk). I have easy access to my stove outlet (NEMA 14-50) which is on a 40A breaker in the panel.

I want to use a 50A gfci spa panel (found one used for 70$ instead of 200$ here in Canada...). Can I use it since it's higher than the 40A? I'm guessing the answer is yes.

I'll use 1 5500w camco element which would need 23A at most on 240V. I could always use a 4500w element instead for lower amp. Do I need to use 8 gauge wire since it's on 40A breaker or since I'll only use 23A I can go with 10? I'm guessing yes again (or hoping it is).

Size of the wire is always based on the breaker. The thing is, if you get a short, the wire will heat up. The breaker opens the circuit before you exceed the ampacity of the wire. So you need thicker wire with a 50 amp circuit than a 40 amp circuit. NEVER SIZE WIRE JUST ENOUGH FOR THE ELEMENT. Check your CSA requirements.

 

[golfindia]

I don't see the need to use wire any larger than what goes from the breaker to the stove. But I'm not an electrician.

 

[thekraken]

[Deleted]

Disclaimer: I'm not an electrician. I'm just some idiot on the internet. Please don't burn down your house or electrocute your cat, that might be bad.

 

[guillaume]

Thanks for the answer. I guess I'll have to use 8 gauge wires then since it's a 40A breaker.

 

[thekraken]

If the very first thing that the extension chord ties into coming out of the 40 amp receptacle is a 30 amp breaker, would it then be okay to just use a 10 awg extension chord?

 

[cegan09]

If the very first thing that the extension chord ties into coming out of the 40 amp receptacle is a 30 amp breaker, would it then be okay to just use a 10 awg extension chord?

Use the thicker wire. It doesn't matter that you're going right to a smaller breaker, you're still tied back to a larger one. What if your extension chord gets damaged and develops a short? Do you really want wire that can't handle the current that will be seen before the breaker flips? Is it really worth the fire risk to save a few bucks on wire size?

Size wire to the source feeding it, not what it's feeding into. If your panel at the end of the extension chord only has 30amp breakers you can use smaller wire from that point forward, but not before it.

 

[golfindia]

Why put a 30A breaker after a 40A breaker?

 

[thekraken]

The smaller the awg wire you can safely use the easier it is to work with. Also cheaper.

 

[stevehaun]

I don't think you can put a 30 amp breaker in series with the 50 amp gfi breaker in a spa panel. They hook up to the same bus bar, i.e., they receive their power from the same source. So you can have one line running into the panel and two lines running out (one gfi protected and one not. Some spa panels have enough room inside to install two 30 amp fuses to safely step down to 10 gauge wire. In the picture you linked for an example you could place two 30 amp fuses between the 50 amp gfi breaker and the 30 amp outlet.
http://www.hazardhomebrewing.org/wp-content/uploads/2013/12/IMG_1421.jpg

Something like this:
http://www.ebay.com/itm/152433832299?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

 

[thekraken]

Yep, didn't think that through. I'll delete for safety's sake.

 

[augiedoggy]

I don't think you can put a 30 amp breaker in series with the 50 amp gfi breaker in a spa panel. They hook up to the same bus bar, i.e., they receive their power from the same source. So you can have one line running into the panel and two lines running out (one gfi protected and one not. Some spa panels have enough room inside to install two 30 amp fuses to safely step down to 10 gauge wire. In the picture you linked for an example you could place two 30 amp fuses between the 50 amp gfi breaker and the 30 amp outlet.
http://www.hazardhomebrewing.org/wp-content/uploads/2013/12/IMG_1421.jpg

Something like this:
http://www.ebay.com/itm/152433832299?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

You sure can , lots of folks like myself use a 30A breaker in the main panel and a 50a GFCI spa panel down the line for the gfci function and or as a power switch like me... the gfci function works the same way regardless of amp load on it at the time. and the 30a breaker feeding the whole thing still protects the circuit.

I have a 30A circuit and my brewery uses a 4500w element for the HLT, 1800w element for the rims (which I can run at the same time as my HLT element along with my panel and DC pumps and still be at like 28amps peak with multiple pumps running and everything at 100% which is unrealistic)
and a 5500w element in my BK... no problems and Ive never had the 30a breaker trip in 4 years.

Oh yeah I use 12 awg sj00w wire thats rated for 25amps from my control panel to my kettles... they are protected with 25a, 20a and 10a glass fuses respectively. No need for fancy breakers inside the panel feeding each element unless you plan of doing stuff wrong and pop a lot fuses..

 

[stevehaun]

Augiedoggy:
I think you misunderstood my post. Yes, you can have a 30 amp breaker in the main panel and a 50 amp gfi breaker in a spa panel which would in fact be "in series". This is commonly done and is totally safe.
What I was referring to was thekraken's suggestion to add a 30 amp breaker to the spa panel itself and then wire them "in series" which cannot be done because both breakers will be attached to the same bus bar.

 

[thekraken]

Well to be fair I wasn't suggesting to wire them in series, that's just what would have wound up happening if one had done what I described :smack:

 

[stevehaun]

Actually, they wouldn't have been in series which is the problem. I contemplated exactly what you proposed when I read that spa panels had room for extra breakers. But, unfortunately, it won't work.

 

[thekraken]

I just can't win today!!! What I suggested would have put them in parallel, no bueno. Know what I mean, not what I say..... I quit now

 

[guillaume]

Thanks for the answers, this clears any doubt I previously had.

Now, if I wanted to add a switch between the breaker and my 50A ranger outlet (or right after the outlet in my panel), what would I use? I've seen contactors and other things suggested, but not quite sure how they work.

Can I use a SSR with a key switch? This would be the cheaper solution, right?

 

[augiedoggy]

Thanks for the answers, this clears any doubt I previously had.

Now, if I wanted to add a switch between the breaker and my 50A ranger outlet (or right after the outlet in my panel), what would I use? I've seen contactors and other things suggested, but not quite sure how they work.

Can I use a SSR with a key switch? This would be the cheaper solution, right?

you would need a dual pole ssr which costs more than the $9 a 2 pole 30A contactor (relay) would cost on amazon or ebay and the contactor would actually be easier to wire up and install... you still need an ssr to control at least one pole of the element to turn it on and off.

 

[brewman !]

if the very first thing that the extension chord ties into coming out of the 40 amp receptacle is a 30 amp breaker, would it then be okay to just use a 10 awg extension chord?

yes !

 

[guillaume]

My main breaker is 40 amp, not 30, but yeah, 2 SSR plus heatsinks price at 22$ on Amazon and a contractor rated for 40 amp for 34$. But I've found a switch rated for 40 amp instead. https://www.amazon.ca/dp/B00GWFN9WS/?tag=skimlinks_replacement-20

In the end, this will cost me around 350$ for a single 5500w element, spa panel and control panel with an EZBoil (10$ more than regular PID). Heck, a new Spa panel goes for over 200$ from the hardware stores, but found one used for 70$. Not even thinking of RIMS or HERMS yet...

 

[augiedoggy]

My main breaker is 40 amp, not 30, but yeah, 2 SSR plus heatsinks price at 22$ on Amazon and a contractor rated for 40 amp for 34$. But I've found a switch rated for 40 amp instead. https://www.amazon.ca/dp/B00GWFN9WS/?tag=skimlinks_replacement-20

In the end, this will cost me around 350$ for a single 5500w element, spa panel and control panel with an EZBoil (10$ more than regular PID). Heck, a new Spa panel goes for over 200$ from the hardware stores, but found one used for 70$. Not even thinking of RIMS or HERMS yet...

I think you need to do more research... Just because you have a 40amp main service doesnt mean your control box needs to have everything rated for 40 amps... You can just install a $-$5 25amp breaker or fuses to be safe and a regular $9 30a contractor wired to a $11 ssr+heatsink and the standard ezboil is like $45... You can easily use a 12x12x8 carlon electrical box/enclosure from the home depot or lowes which is $35 and build the whole thing safely and to code for under $200 with the plugs and cords..about $275 with the $35 all stainless ripple element and the $55 spa panel. your control box plugs in so it doesnt have to meet the requirements of the circuit... If that were true your cell phone charger would be $50 and have 14-12 awg wire because your plugging it into a 15-20a household circuit. and every lamp in your house with a little 40w bulb (or much less now) would have to have fuses or breakers in them but you dont see that either..

The 3 element control box in my avatar cost me under $300 to build and I control 3 dc pumps and a timer with it... (I even added the 300 model ezboil later for $55)

I bought my new 50A spa panel at the home depot for $60... I didnt even pay near that much for the 60A spa panel my actual spa uses...

BTW theres a reason those rotory switches arent ideal.. I suggested then myself to someone a few months ago and Doug pointed out why they are not ideal... not to mention wet hands near a switch with the potential of 40A is not very safe... a $1.30 10a switch like this http://www.ebay.com/itm/360982216727 along with this contactor http://www.ebay.com/itm/Hvacstar-SA...057982?hash=item338c880abe:g:AWwAAOxyUI1TJxin and you are much better off... I use a few of the same switches and even the same contactors in some of my builds.

 

[guillaume]

I think you need to do more research... Just because you have a 40amp main service doesnt mean your control box needs to have everything rated for 40 amps... You can just install a $-$5 25amp breaker or fuses to be safe and a regular $9 30a contractor wired to a $11 ssr+heatsink and the standard ezboil is like $45... You can easily use a 12x12x8 carlon electrical box/enclosure from the home depot or lowes which is $35 and build the whole thing safely and to code for under $200 with the plugs and cords..about $275 with the $35 all stainless ripple element and the $55 spa panel. your control box plugs in so it doesnt have to meet the requirements of the circuit... If that were true your cell phone charger would be $50 and have 14-12 awg wire because your plugging it into a 15-20a household circuit. and every lamp in your house with a little 40w bulb (or much less now) would have to have fuses or breakers in them but you dont see that either..

The 3 element control box in my avatar cost me under $300 to build and I control 3 dc pumps and a timer with it... (I even added the 300 model ezboil later for $55)

I bought my new 50A spa panel at the home depot for $60... I didnt even pay near that much for the 60A spa panel my actual spa uses...

BTW theres a reason those rotory switches arent ideal.. I suggested then myself to someone a few months ago and Doug pointed out why they are not ideal... not to mention wet hands near a switch with the potential of 40A is not very safe... a $1.30 10a switch like this http://www.ebay.com/itm/360982216727 along with this contactor http://www.ebay.com/itm/Hvacstar-SA...057982?hash=item338c880abe:g:AWwAAOxyUI1TJxin and you are much better off... I use a few of the same switches and even the same contactors in some of my builds.

My 5500w element will draw 23amp at top, I've been told to use 40A wires and not only rated for the element (so use 8 instead of 10). Of course I would prefer to size everything for 30A. I prefer to lean on the safe side, plus I can easily upgrade later when I'll have room for HLT and a RIMS.

I've got an Excel sheet with all parts and costs, here's an overview :

My spa panel cost me 70$ used because here in Canada (for no apparent reasons...) a spa panel cost over 200$ new (see here). I could always order one online new, but they still run around 100-140$. Most (all) gfci breaker on amazon.com won't ship to Canada. That Ezboil cost me 60$ with shipping and taxes. Stove cord? That's 20$ (even on amazon, 16$ + shipping is the lowest I could find). A 5500w camco element cost me 46$ with free shipping.

Only for the bare minimum (SSVR, element, box, cord, spa panel), this setup would cost me over 240$. I choose to go the PID path and picked EZboil since it only cost 10$ more than a "regular" PID.

Here's my setup : PLAN (PDF)

 

[augiedoggy]

if we are talking about the wire inside and after your control panel than you were told wrong... 12 awg SJ00w is rated for 25a and all thats needed... and you can actually use 12 or 10 awg inside your panel. and like I said if your concerned about it the safest way to meet code and make this conversation a non issue is to put 25A fuses or breakers on each hot line inside your control panel right after it comes into the panel and the wire size is stepped down. or even replace the 40a breaker in your main panel with a 30a one although I wouldnt do that... instead id go with the fuses which are cheap and will protect in the unlikely event of an issue.

 

[augiedoggy]

I would go with the camco with the stainless base or this one http://www.ebay.ca/itm/240v-5500w-R...132201?hash=item282c5f4229:g:S6IAAOSwr~lYrKsb the normal stainless hot water tank ripples sold by camco have a zinc plated steel base which often rusts.(you do not want the 02964 model). The all stainless version of the camco is very expensive.

If you go with 2 4500w elements like these they only draw 18 amps and you can run both at the same time or a rims with one easily.. plus they have the stainless base.

http://www.ebay.ca/itm/Dernord-240V...765509?hash=item5d696dda45:g:7EsAAOSwLnBX9A6u

and as far as your prices, I hear you... We may be in the same boat soon if Trump get his way..

 

[guillaume]

if we are talking about the wire inside and after your control panel than you were told wrong... 12 awg SJ00w is rated for 25a and all thats needed... and you can actually use 12 or 10 awg inside your panel. and like I said if your concerned about it the safest way to meet code and make this conversation a non issue is to put 25A fuses or breakers on each hot line inside your control panel right after it comes into the panel and the wire size is stepped down. or even replace the 40a breaker in your main panel with a 30a one although I wouldnt do that... instead id go with the fuses which are cheap and will protect in the unlikely event of an issue.

So put 30A breaker inside my control panel, after the spa panel? I'll use 14 to the PID and from PID to SSR, rest is 8. Might be cheaper to use the SJ00w from control panel to the element, I'll check that, thanks for the input.

I'll use this element : https://www.amazon.ca/gp/product/B000BPG4LI/?tag=skimlinks_replacement-20

 

[John Eberly]

Hold on -

#12 wire is thermally capable of 25 amperes but overcurrent protection is limited to 20 amperes. (US rules, pretty sure Canada is the same).

SJO cord should never be used for point-to-point wiring. It's rated for cord use only and one or both ends should have a cord body (plug) attached for plug-in service.

You will be really disappointed if you try to run #14 from your 30A overcurrent protection to the PID and the SSR and then run the rest of the circuit in #8. Smoke and flames will escape. Unless you are talking about using lighter wire for controls. All of the power wire needs to be the larger gage.

 

[augiedoggy]

Hold on -

#12 wire is thermally capable of 25 amperes but overcurrent protection is limited to 20 amperes. (US rules, pretty sure Canada is the same).

SJO cord should never be used for point-to-point wiring. It's rated for cord use only and one or both ends should have a cord body (plug) attached for plug-in service.

You will be really disappointed if you try to run #14 from your 30A overcurrent protection to the PID and the SSR and then run the rest of the circuit in #8. Smoke and flames will escape. Unless you are talking about using lighter wire for controls. All of the power wire needs to be the larger gage.

I use this type of wire http://www.awcwire.com/part.aspx?partname=sjoow-12/3 or https://www.wireandcableyourway.com/12-3-sjoow-portable-cord-300v-ul-csa.htmlas you can see its rated at 25amps... I never had an issue the cable doesnt get hot. for a plug in cord I believe this specific cable is ok for this since its not permanent and a non continuous load and not running at 100% for over 3 hours consecutively it doesnt matter. the 80% rule doesnt apply here. Its an appliance.

and a pid uses less then 1/2amp its absolutely silly to run 10 awg wire to power it since its still just as likely to go poof before the wire to it does if theres any failure they should be fused externally in an ideal situation... again thats solved with a $2 inline fuse and holder. As long as all independent smaller circuits are fused your good but even if you didnt add them you will not see any smoke or flames unless something became physically damaged somehow... The machinery I repair for a living is powered by a 50A 380 main and the pids inside are powered by 18 awg on their own breaker. My first control panel is 4 years old and I run 18 or it might even be 20 awg to power the pids... no flames or smoke that you speak of. by your reasoning if I plug a lamp in with a 16 awg power cord I should see the same smoke right? since the plug its plugged into is fused for 20a and the wire in my walls feeding it is 12 awg? why is something sealed in an enclosure not safe but something sitting on the floor where it can be pulled, damaged or frayed ok in this scenerio? The logic here escapes me?

pids run on 24v in most cases and your just feeding the ac power to their internally fused 24v dc powersupplies inside.
lets not forget we will already have the 25amp fuses or breakers as well as the GFCI for overcurrent protection here on the elements... it would be silly to run #8 wire to the element..With that logic, then it becomes the weak link without overcurrent protection that could go poof and smoke anyway right?

 

[guillaume]

Hold on -

#12 wire is thermally capable of 25 amperes but overcurrent protection is limited to 20 amperes. (US rules, pretty sure Canada is the same).

SJO cord should never be used for point-to-point wiring. It's rated for cord use only and one or both ends should have a cord body (plug) attached for plug-in service.

You will be really disappointed if you try to run #14 from your 30A overcurrent protection to the PID and the SSR and then run the rest of the circuit in #8. Smoke and flames will escape. Unless you are talking about using lighter wire for controls. All of the power wire needs to be the larger gage.

Have you checked my plan? plan in pdf

 

[itsnotrequired]

Hold on -

#12 wire is thermally capable of 25 amperes but overcurrent protection is limited to 20 amperes. (US rules, pretty sure Canada is the same).

SJO cord should never be used for point-to-point wiring. It's rated for cord use only and one or both ends should have a cord body (plug) attached for plug-in service.

this isn't quite correct. the 20 amp maximum overcurrent protection rating for #12 awg copper conductors, which is identified in nec 240.4, does not apply to flexible cords. 240.5 is the section that applies to flexible cords and that references the ampacities identified in 400.5, where #12 is indeed indicates as 25 amps. but there is a wrinkle in this...

nec 110.14(C) addresses terminations and temperature limitations. unless marked for higher temperatures, termination of #12 awg conductor needs to use the 60 degree c amapacity charts in table 310.15(B). note it doesn't say 'whatever ampacity chart applies to the type of conductor' but rather explicitly identified 310.15(B). the ampacity of a #12 conductor in the 60 degree c column is only 20 amps, which would require a 20 amp breaker for protection. now, it is not uncommon for smaller electrical equipment to carry 75 degree c termination provisions. if that is the case, the 75 degree c column of 310.15(B) can be used, for which #12 is rated 25 amp and a 25 amp breaker could be used.

the above is an extremely fine point that also happens to be debated in the electrical industry but is important to note that conductor amapacity alone cannot be used as a justification for determining overcurrent protection requirements.

and you are correct that flexible cord is not a substitute for premise wiring. for example, you cannot run flexible cord from a panelboard to a brew panel. the flexible cord is perfectly fine from the panel to the elements.

 

[thekraken]

and you are correct that flexible cord is not a substitute for premise wiring. for example, you cannot run flexible cord from a panelboard to a brew panel.

Wait, what do you mean by panelboard? This doesn't apply to all of our 240v chords that run from receptacle to brew panel? Just talking about a permanently fixed brew panel?

 

[itsnotrequired]

cord from a recep to a brew panel is fine, whether the brew panel is fixed to the wall or not. cord from the main house panelboard (or a sub-panel) to that main receptacle would not be allowed. i'm not saying it is dangerous, just doesn't meet code.

 

[ajdelange]

I don't know if this will clarify or muddy the waters at this point but there are two essential factors here
1) The circuit breaker in the supply panel is sized to protect the wires to the load
2) Any current limiting disconnect required by the equipment manufacturer is sized to protect the equipment. It can be of smaller size than the breaker at the panel with which it is 'in series'.

Example: Dual compressor heat pump with each compressor fed by #6 and a 60 Amp breaker. One load is protected by a 50 Amp disconnect/fuse/breaker because it is only a compressor. The other by a 60 amp disconnect/fuse/breaker because it consists of a compressor and a couple of pumps.

[EDit: Reworded to make it clear that it is the loads being protected by the current limiting devices in the disconnect]

 

[guillaume]

I don't know if this will clarify or muddy the waters at this point but there are two essential factors here

At this point, I'm out loll I'm a graphic designer, not an electrician Someone make a TL;DR I can put in my first post ?

But, I understand that using 8awg from outlet to panel is OK (I'm using range cord anyway which is rated for 50A). The PID (EzBoil) AC input (add a fuse here) and the SSR input with 14awg.

Was only wondering if using 10awg from control panel to element was ok since it's using 23 amp at top, calculate 28 amp for safety. I think that part is cheaper, but not enough to takes risks

 

[stevehaun]

Yes 10 gauge from panel to elements is ok if you have 30 amp breaker or fuses in the panel.

 

[augiedoggy]

The reality is 10 or 12 is fine (and DOES meet code) for the cord from the control panel to 23amp load since again the 80% safety rule is for continuous loads that last over 3 hours in a permanently wired application... A free standing plug in power cord such as the sj cord has different rules and the 12g is allowed and rated for 25a... Its much more flexible and easier to manage and that as well as cost is why I use it...

 

[guillaume]

Just saying, I used 30A breaker in main panel, 50A spa panel and #10 from main panel to spa panel, to the control panel and also to elements.