Control Panel Power Distribution

Here's a question...follow me on this one. Could you set-up two of these 1-in/4-out power distribution blocks on 2 circuits sharing the same ground on one terminal?


http://www.automationdirect.com/adc/Shopping/Catalog/Power_Products_(Electrical)/Power_Distribution_Blocks/Open_Style,_UL_Recognized,_175A-760A_(PB_Series)/PB1043

Block A: Would service a 110v circuit with L1 (Hot), Neutral, and ground connected to it.
Block B: Would service a 240v circuit with L1, L2, and Neutral connected to it, but have the ground from this circuit shared with the ground on Block A?

Trying to figure out a way of incorporating 2 circuits without making a mess inside the control panel and keeping it clean. Since the 240v circuit is 30 amps and powering a 5,500 watt element, let's assume its a dedicated circuit to the element. Power/control for pumps, PID, HLT stirrer, etc. will be supplied by the 110v circuit rated for 20 amps.

Can one side of the distribution block be used for a ground? Can that ground be shared with other circuits provided the neutral is maintained separately? I'm pretty sure you can but in over-thinking things I always get myself confused...

Also, what size/type wire do you use to wire up the PID? Does it have/need a ground? Should I fuse it?

Yeah you should be able to do that. Ground is ground. Sharing it should not be a problem. Like you said the neutral is the one you want to be careful sharing.

I put a fuse on my PID. Mine is 12v so I have + and - no ground. I would check the directions. It should tell you if you need the ground. As for the size wire. Check the amperage draw of the PID. That will determine what size wire you need. I bet you could get away with 16 guage stranded. If not 14awg will for sure cover it.

I am planning to use two of these in my setup, but I am also going to use a sepperate ground bar. These blocks will both have L1,L2, and N in them with one being fed through and e-stop circuit from the other. This will allow me provide power to the control, e-stop circuit and other things I might want powered at all times with one block and then provide power to everything behind the e-stop with the other. I think it is probably a bit cleaner to keep all of the grounds going to one central ground bar, but what you are suggesting would certainly work.

Kind of what I did.

Just finished mine this weekend. Still need to put on finishing touches though. I removed the electrical components from the spa panel and mounted in my control panel box. So far i am just using the GFCI from this circuit. I built my own power cord. I ran a 6 gage 4 amp wire to it even though it is only using 30A or 40A (depending on whether I choose to run it from the dryer or stove outlet) and 240/120 wire with no ground. I am using the heavier wire on it so I can upgrade in the future if i can find a 50 amp 240/120 grnd outlet or circuit down the road. So there is a monstrous 9' tail on my control box which aims to be portable.

For the other circuits (120V). I have a 3 foot 12/3 sjoo cord that I ran to 3 different grounding bars one for positive neutral and ground. This small cord will tuck back into the box for transport then be plugged into a GFCI in the kitchen wall with an extension cord. So far I have run only the PID off this circuit. I used 12ga THHN wire to run to the PID with a 1amp fuse. I used solid wire but regretted it I will change this out to stranded THHN before this weekend. The instructions for the PID said the wire feeding the PID must be rated for 600V. Not sure why this is needed but it is called for.

The ground from the GFCI circuit will supply all my grounding needs for both 120 and 240 circuits. I did pull a ground to my switch and outlet in the back for the element cord. There is no space for grounding though on the water heater element.

I did not have time to finish up or test it yet. I was busy building legs for the control panel and will hopefully have it up and running for a test this weekend and will post better photos then. In the meantime if anyone can help me with these questions?

Do i need to ground the keg?
What should be grounded in this setup or panel?
Anyone know why the need for 600v wire to the PID?

Sorry for the hijack.

for what we use these for, they are massive. i switched over to DIN rail terminal blocks with jumpers for the control box i'm working on now.

http://www.mcmaster.com/#7641k51/=61plp9

edit: fixed the link.

p.d.

paledragon said:

for what we use these for, they are massive. i switched over to DIN rail terminal blocks with jumpers for the control box i'm working on now.

http://www.mcmaster.com/#7641k51/=61plp9

edit: fixed the link.

p.d.

Click to expand...

Any difference between these din rails and my setup besides modularity of the din rails? I think my system is solid but am unsure of mounting all this wiring not in an NEC box.

Photopilot said:

Any difference between these din rails and my setup besides modularity of the din rails? I think my system is solid but am unsure of mounting all this wiring not in an NEC box.

Click to expand...

i think you need to do more homework before plugging that thing in. some notes (i don't mean this to come across harsh here):

- i don't think there's such a thing as an NEC box. you probably mean NEMA rating. not a huge deal there.
- you said you had a black wire going into a grounding bar. black implies hot. not good.
- that grounding bar appears to be mounted to wood inside a metal case. not good.
- everything metal gets grounded. enclosures, kegs, elements, etc. not understanding this hints that you need to do some more reading.
- 600V ratings are standard for enclosure wire.

p.d.

Code Rage put together a nice guide electrical-primer-brewers I would recommend reading it it my help.

Ground wire needs to be sized the same size as the supply wires.

Thanks P.D.
No offense taken. I am asking around and looking for suggestions before its maiden voyage. I admit some ignorance. I have done house wiring but am out of my element outside the confines of that element.

paledragon said:

- you said you had a black wire going into a grounding bar. black implies hot. not good.

I am using "grounding bars" only as a distribution block. I have one for hot, neutral and grounding. Each are separate entities.

- that grounding bar appears to be mounted to wood inside a metal case. not good.

I figured the wood would act as a neutral insulator for the electrical elements. Any suggestions on how to mount this without the wood? Would the DIN rails allow me to mount into the box and maintain insulation without energizing the box?

- everything metal gets grounded. enclosures, kegs, elements, etc. not understanding this hints that you need to do some more reading.

I can pigtail to a ground screw to the enclosure and the power cord to the element will have a ground in it. I can use it to run a ground screw in the kegs base. How do i add a ground to the water heating element?


p.d.

Click to expand...

thread jacked.

illin8 said:

Here's a question...follow me on this one. Could you set-up two of these 1-in/4-out power distribution blocks on 2 circuits sharing the same ground on one terminal?


Block A: Would service a 110v circuit with L1 (Hot), Neutral, and ground connected to it.
Block B: Would service a 240v circuit with L1, L2, and Neutral connected to it, but have the ground from this circuit shared with the ground on Block A?

Trying to figure out a way of incorporating 2 circuits without making a mess inside the control panel and keeping it clean. Since the 240v circuit is 30 amps and powering a 5,500 watt element, let's assume its a dedicated circuit to the element. Power/control for pumps, PID, HLT stirrer, etc. will be supplied by the 110v circuit rated for 20 amps.

Can one side of the distribution block be used for a ground? Can that ground be shared with other circuits provided the neutral is maintained separately? I'm pretty sure you can but in over-thinking things I always get myself confused...

A

Click to expand...

Brewmoor said:

Yeah you should be able to do that. Ground is ground.

Click to expand...

NOOOO!!!!!!!!!!!!

Those are insulated!!!!! With a ground, EVERYTHING must be bonded. Get separate ground bar, screw it directly to your metal enclosure, and bring all of your grounds to that.

You people really scare me. If you don't know what you are talking about, DON'T GIVE ADVICE! Sorry if that seems rude, but somebody is gonna get killed one of these days.

Thanks Bernie, thats exactly why I posed the question. i hadn't seen it done before, although it 'makes sense', I know better than to assume it is ok.

What if my control panel isn't a metal enclosure but a NEMA plastic box? Does it matter? The grounding bar doesn't have to be anything special right, will a bar from Home Depot do?

illin8 said:

Thanks Bernie, thats exactly why I posed the question. i hadn't seen it done before, although it 'makes sense', I know better than to assume it is ok.

What if my control panel isn't a metal enclosure but a NEMA plastic box? Does it matter? The grounding bar doesn't have to be anything special right, will a bar from Home Depot do?

Click to expand...

That's fine. Use one similar to the one in PhotoPilots' pics. Just don't use it for anything but ground.

Bernie Brewer said:

NOOOO!!!!!!!!!!!!

Those are insulated!!!!! With a ground, EVERYTHING must be bonded. Get separate ground bar, screw it directly to your metal enclosure, and bring all of your grounds to that.

You people really scare me. If you don't know what you are talking about, DON'T GIVE ADVICE! Sorry if that seems rude, but somebody is gonna get killed one of these days.

Click to expand...

What are you ranting about? You told him the same thing we did. He asked if he could bring all the grounds together. Yes he can. That is what I said and you just said it too.

and yes it was kinda rude. I do know what I am talking about. I have worked as a commercial electrician and have done a ton of stuff with electronics too. So maybe explain yourself a bit more before shouting at people.

illin8 said:

What if my control panel isn't a metal enclosure but a NEMA plastic box? Does it matter? The grounding bar doesn't have to be anything special right, will a bar from Home Depot do?

Click to expand...

You can use a standard ground bar from HD. You can use the distribution block you posted in the beginning too. You can't bond anything to plastic. So the fact that the distribution block is insulated is a null point. Make sure you have a good connection to ground at your panel. Also make sure you attach a ground to your kettles and anything else metal on your rig.

Get yourself a GFCI breaker or cord for this thing too.

Thanks for the input. With all the safety concerns associated with electric rigs I think we all need to keep things in perspective on HBT. Some people bring more electrical experience than most, others (like myself) have a pretty decent understanding of it but need clarification on specific components. Threads on these topics are good avenues to sort out what can/can't and should/shouldn't be done. I respect the experience of others, which is the reason for the post in the first place and think it's a great way to get it out there for those trying to understand it. Sometimes responses may come across harsh but I respect them nonetheless, it comes from experience which is why the question is being asked...

My rig will have a 30amp GFCI cord connected to an existing 30amp dryer outlet with ground. The ground will be tied from the kettles back to the dryer outlet. I'm just trying to distribute the power cleanly without getting too complicated.

Brewmoor said:

What are you ranting about? You told him the same thing we did. He asked if he could bring all the grounds together. Yes he can. That is what I said and you just said it too.

and yes it was kinda rude. I do know what I am talking about. I have worked as a commercial electrician and have done a ton of stuff with electronics too. So maybe explain yourself a bit more before shouting at people.

Click to expand...

well then one of us obviously misunderstood what he intended to do. I took it that he was going to bring all the grounds into one of the insulated lugs. Unless it is an isolated ground, you don't do that, because the equipment isn't bonded. If I was wrong in my interpretation, I apologize. But I don't think i interpreted it wrong.

What I had inquired about was taking one ground from one circuit and one ground from another and connect them to one lug (shared) of a distribution block. I wasn't going to use a metal enclosure but was planning on plastic (if it makes a difference).

Well that one lug if I looked at the picture correctly has one large hole and screw. (ground from panel) and distributes to 4 smaller screws. (ground to devices).

In that case you can connect 5 grounds to that one lug. That would be no different then using a ground bar from HD because the box is plastic. No need for the insulated lug to be grounded to the box. If it were a metal box you would want to take a leg from the lug and bond it to the box or use an un-insulated ground bar that is screwed directly to the box.

Well, when I saw it I assumed a metal enclosure. And he made no mention of running a pigtail to the box, so I assumed an unbonded box, which is not a good thing.