Which comes first - the contactor or the bus bar?

[WhiteArmadilloBrewing]

I've got 240v & 120v power coming from my spa panel into my control panel. I have the GFCI protected 120v going directly to bus bars that power a split outlet for my two pumps.

I would like to start wiring my contactors, ssrs, din rail breakers, and fuses but couldn't find a straight answer on the best practice. I believe that based off searching this forum and the electric brewery forum that my wiring should proceed as follows:
---
Neutral & Ground run directly to bus bar

2 Hot Legs to (separate?) contactors 1st then to terminal blocks/bus bars with a switch wired to the contactor which acts as an on/off
---

Any help would be great! Cheers!

 

[universalfrost]

winner winner chicken dinner...

lol

yeah you could run it that way with two contactors or run a three pole contactor for the power in.. make sure to have the appropriately rated contactor

 

[FastTalker]

What’s the point of the bus bar after the contactor? Typically your pump would come after the contactor. A rough sketch might make your question a little more clear.

 

[WhiteArmadilloBrewing]

What’s the point of the bus bar after the contactor? Typically your pump would come after the contactor. A rough sketch might make your question a little more clear.

To power elements, SSRs, PIDs, etc... Otherwise how would I run power to all of these?

 

[FastTalker]

Just making sure I understand your question. It wasn’t clear if your using contactors to control your pumps or using it to switch all your 120V power since you mentioned separate contactors. Again a sketch would go a long way.

 

[universalfrost]

This is what I am doing, but I am running a separate 120v 20 AMP line in for the pumps like what you want to do... I'll still have the extra connectors for 120 coming from the 240 like in the drawing, in case I need them for some reason or another.

 

[FastTalker]

Universalfrost's wiring diagram looks like what you want to do.

Why a separate 120V feed? You already have the 2 phases and the neutral.

 

[augiedoggy]

To power elements, SSRs, PIDs, etc... Otherwise how would I run power to all of these?

Ssrs get powered off the pids which ideally get connected to 240v to help balance the gfci protected load.. All these can run off a single 1/2amp protected fused line really.. They draw practically nothing and use half the total avaliable amp draw in 240v mode then they would if wired to 120v.

If you want to have a power switch in the panel you want one 2Pole contactor to control all the power and have the 120v circuit (or 240v if you use that) to be wired after the main power disconnect contactor. If you would rather unplug the panel to turn it on and off (Why I dont know) you can have the pid and such power circumvent the main power contactor relay.

 

[augiedoggy]

Just making sure I understand your question. It wasn’t clear if your using contactors to control your pumps or using it to switch all your 120V power since you mentioned separate contactors. Again a sketch would go a long way.

pumps draw a lot less than your typical 10a rated 22mm control panel switch so using contactors to turn them on and off here would be kind of silly.

 

[FastTalker]

pumps draw a lot less than your typical 10a rated 22mm control panel switch so using contactors to turn them on and off here would be kind of silly.

You're making a lot of assumptions about what he is doing. No where did I see anything about a 22mm switch.

 

[augiedoggy]

You're making a lot of assumptions about what he is doing. No where did I see anything about a 22mm switch.

Not really.
A standard control panel or most AC rated switches for that matter are rated for 10amps or more.. Since this is a control panel he's building, and hes using other devices designed for control panels like auber ezboil co trollers and contactors and SSRs... It's a fairly safe assumption (A lot more likely than assuming they are not anyway) his switches would be the type designed for a control panel as well... but even if he's using a wall light switch or metal rocker switch from the home depot, it's rated for directly switching power to the pumps. There's really no scenario here where using contractors make more sense for this use. He has also mentioned his intents and using multipostion switches for switching controllers and outputs in other threads if it helps.

 

[FastTalker]

I just like to make sure people are doing things safely. A lot of the people that post in this forum aren't experts at this type of thing. That's why they are asking for help. So I don't like to make assumptions about the decisions they've made. I've seen some questionable advice given in the past to people who didn't know it was wrong.

OP, is your original question answered?

 

[WhiteArmadilloBrewing]

Yes, sort of... I understand the "step down" ability of utilizing a contactor when implementing lower rated switches to handle the loads instead of trying to find 30-50a switches/buttons to power things on and off.

What I was attempting to find out is really how many contactors I need to be within safe parameters for switching/powering all the devices and elements in my control panel?

I.E. if I run both 240v hot legs to separate contactors then from the contactor to a bus bar does that allow me to run:

(1) 10g wire to my HLT & BK 240v elements from those bus bars?

• Or does this negate the power needed for those elements?

(2) smaller gauge wire to the the ssrs, PIDs, breakers, fuses, etc. from those bus bars?

• Or does that push too much power through these parts of the control panel?

If not, then do I need to run a separate contactor for main power on/off, each 240v element, etc. like the drawing attached in #6?

 

[universalfrost]

one main contactor for emergency power off, separate contactors for each element.. total of 3 if only running two elements... or 4 if running 3 elements...