Transfer Panel / Transfer Switch Options

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  #1  
Old 03-22-14, 05:01 AM
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Transfer Panel / Transfer Switch Options

OK Gang. Finally I am getting around to this project - wiring a inlet for the generator.

Generators : EU6500is & Dual EU2000is on hand

The challenge is whether to go transfer switch or panel.
The majority of the transfer panels I am looking at - Generac or Reliance, all seem very similar. It's a quasi sub-panel with a interlock .

The transfer switch - Reliance Q310 was my 1st option.

My current panel circuit runs have NO slack when it comes to the the cable going into the panel *all BX* . It's all terminated into the main panel pretty snug with no slack. Rerouting the gen powered runs to a transfer panel would entail a creative way removing the circuits runs from them main panel - hopefully getting some slack, splicing in a splice box and then extending it into the panel.


Option B: Going the transfer switch route. This has it's challenges as well. The built in leads on the Q310 is not long enough but it's wired in such a way that I can't just remove the existing wire and rewire it back to the main panel in a single run.

So it's would be
Transfer Switch Leads-Short Nipple-Pull Box
Splice all leads back into Main Panel from Pull Box
(I do have some volume concerns just due to adding a additional 12 more wires into the main panel box - 10 for the circuits, and then 2 for the switch ground/neutral)


I don't think I've overlooked this or maybe I am missing other options.
Hence, it was something I had planned to do last year but it did not seem like a easy weekend project given some of the constraints.

In the meantime, I have quite a abundance of various Portable Cords built , with 2 large 10Awg Runs with Quad Pendant Boxes Built as my *running cords out of the generator setup*.

Thoughts, Ideas.
 
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  #2  
Old 03-22-14, 05:17 AM
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Unless I am missing something in your procedure, you don't run your wiring from the existing panel to the switch. The switch has sufficient numbered wire for you to pigtail in the existing panel and make final connection to the breakers. The metal whip contains it all and attaches directly to the main panel. The only other connection you will have to make is your inlet, and whether to use an internal one on your switch or an external one mounted with a weatherproof cover.
 
  #3  
Old 03-22-14, 05:28 AM
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The WHIP only has 3 feet of lead on it. I'm short 3 feet (just due to the wall on which the main panel lies). Hence the splice box requirement....

So regardless or switch or panel, the new *gen transfer* panel would be located 4 feet or so away from the panel.
 
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Old 03-22-14, 05:51 AM
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Just a curious question....why so far? The switch can be mounted nearer the panel and your inlet extended.
 
  #5  
Old 03-22-14, 08:08 PM
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There is something in the way - hence the best possible location for any ~gen~ panel is about 4 feet away from the main. So figure another 12-18 of how it routes in the main panel - hence the 5'ish feet of wire whip, which is much longer than the 3' that comes prebuilt into the transfer switch.
 
  #6  
Old 03-22-14, 08:22 PM
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I was given one of those transfer panels with the 10 circuits to choose and wire... It's still in the box. I put an interlock on the load center and a 50amp breaker to accept the generator plug. I then run the whole house off the generator just making sure to not overload the gen. I wired an amp meter to the generator plug so I can see the load real time.
-=Phyber
 
  #7  
Old 03-22-14, 08:28 PM
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Interlocks are not as safe as transfer panels and not code compliant in many areas. Since he has a safer more likely code compliant way of doing it he should be encouraged to do it that way.
 
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Old 03-22-14, 08:53 PM
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I'd argue the safety equivalence of the two solutions. And the code compliancy as well, but that's been done all over the internet already. I was just passing on what worked for me, and it is a much easier install and operating process. That being said... carry on.
-=Phyber
 
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Old 03-23-14, 06:50 AM
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Just for clarification the main issue with interlocks is most can be defeated by removing the breaker box cover. That is especially true of non UL approved ones of which there are many. Some panel manufacturer's panel specific ones work even with the cover off.
 
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Old 03-23-14, 06:52 AM
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I'd argue the safety equivalence of the two solutions. And the code compliancy as well
Code compliancy is up to the local AHJ, some accept interlock covers and some don't. All codes are local.
 
  #11  
Old 03-23-14, 07:16 AM
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RE: Transfer switch boxes with 10 (give or take) individual transfer switches.

If you don't have enough wall surface next to the panel to install the transfer switch box then you can install the latter somewhere else with a large junction box (pull box) to insert the 3' whip. Try to position the junction box to make the best use of the existing 3' whip. Then build a whip extension using conduit to get from the junction box to the panel. For 10 switches in the transfer box, there are 20 small wires (10 pairs) plus the neutral and ground in the whip. You may not combine any of these wires onto a fatter wire to continue fewer wires on to the main panel.

You may be able to find a flexible conduit that is big enough (or use more than one) and prefill it with the wire pairs while it is lying on the floor and then assemble it to the panel and junction box. Be sure to label each and every conductor at both ends. The main panel will be neater if you precut the extension wires to reach all the way to the respective breakers saving the need for wire nuts just inside where the whip extension attaches to the main panel. However this planning is not easy; you can end up with a lot of wasted wire when cutting everything to the desired lengths during final connection.

Connecting up a branch circuit to a pair of wires (either from the original whip or a whip extension) is straightforward and should not need creativity. You unhook the circuit wire from the breaker in the main panel and connect that wire end to one incoming whip wire (from the common terminal of the corresponding switch in the transfer box and probably labeled "to branch circuit"). The other incoming wire of the respective pair (coming from a side terminal of the corresponding switch in the transfer box and probably labeled "to breaker") is connected to the breaker that was just unhooked from.

Do you have enough space in the main panel to bring a pair of whip wires up to and next to each applicable branch circuit breaker? If the neutral or ground bus is nearby then it will be a little more crowded.

Hint: After choosing the branch circuits to go to the transfer switch box, connect up the ones with the shortest wires originally going to their breakers first. The longer the original circuit wire, the more freedom you have selecting a more spacious location within the panel to wire nut it to the corresponding transfer switch box whip wire.

Connect one pair of wires representing one switch in the transfer box at a time. Test the respective switch in the transfer switch box to be sure it controls the respective branch circuit. Check to be sure you have not energized any inlet prongs when the respective switch is flipped "to generator power" since this indicates incorrect wiring of that pair of wires. After that, go on to the next pair.

When you use a transfer switch box you still need to be careful of what appliances you are using at any given time so as not to overload your generator.

Do not bend a flexible conduit sharply around or into a corner. It must be bent gently, do not force it in any way.
 

Last edited by AllanJ; 03-23-14 at 09:00 AM.
  #12  
Old 03-26-14, 04:17 AM
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AllanJ -

Spot on your comments. Those were the exact route I was going to take. The one additional tip I picked up was to test each circuit individually before going on the next.

I took the Q310 out of the box again. While the breaker mechanisims are nice and ~solid~, the line-off-gen switches for each circuit was somewhat flimsy. A simple tap/movement of the finger and one can move between the ~3 positions~. While this is more a switch, I would have presumed it would be a more positive engaging click required to move beween line-off-gen.

I do like the transfer switch more than the panel. To me, it's making a selective choice when running off the genny.

Time to open up the main this weekend and see if I can ~space~ for the 22 extra new leads
 
  #13  
Old 03-27-14, 05:07 AM
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I think I have a sound plan. Curiousity peaked my interest to open up the panel cover.

It's a older panel with the neutral bar on the right side, next to the right side breakers.

I plan to label all the circuit runs and remove them out of the panel.
Some of my circuit runs are coming out of the left side KO .
If after looking at the runs and hoping there is enough length-slack, I plan to use Duplex connectors and get all the circuits entering from the top of the panel.


Route all non gen powered circuits to the right side of the panel (where the neutral bar is)

Route all gen powered circuits to the left side of the panel.
By me moving all the entrance points that was previously coming on the left side KO, this hopefully gives me some extra breathing space/room to have all the *spliced* common alongside here. Maybe run the slack to the bottom of the panel.


Last question that I'm debating is how much slack will I leave in this panel when all said and done. All new constructions, these sparks are like artists. They leave no slack, but all the wires come in, nice bends into breaker, all wires zip tied, etc.

I purposely have left slack in the box (with the known intent something like this service wise ) would happen.

With the added extra 22 wires coming into the panel, I'm inclined to just cut the circuit runs to where it needs to go and no slack whatsoever.
 

Last edited by pingable; 03-27-14 at 05:30 AM.
  #14  
Old 03-27-14, 05:22 AM
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... Last question that I'm debating is how much slack will I leave in this panel when all said and done. All new constructions, these sparks are like artists. They leave no slack, but all the wires come in, nice bends into breaker, all wires zip tied, etc. ...
Psst! They leave a lot of footage on the cutting room floor.

They prefill the conduit with worst case lengths of wire. Then there are two philosophies: (1) Leave extra loops in the box in case breakers need to be re-arranged later, versus (2) Make each connection as tight as permissible so there isn't "superfluous" wire taking up space in the box. (Extra length is not computed in box fill requirements but can make it more difficult to stuff everything into a box.)

I would not put much effort into pulling cables out of the box and re-inserting them. Perhaps two or three might be relocated but I would think that the space available would support at least a few wire nuts next to applicable breakers, one per. The whip wire going to the breaker terminal does not need a wire nut and takes up "negligible" room.

Pulling and relocating branch circuit cables may have an added complication in having to splice on extra wire (a pigtail) for the neutral.

You do not need to flip breakers in the main panel when changing to generator power.
 

Last edited by AllanJ; 03-27-14 at 05:38 AM.
  #15  
Old 03-27-14, 12:38 PM
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How much is that reliance transfer switch? Over 350?

This is a cheaper option with room to up the input power:

GE 200 Amp 240-Volt Non-Fused Emergency Power Transfer Switch-TC10324R at The Home Depot
 
  #16  
Old 03-27-14, 01:56 PM
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Reliance is about $220 to $350 depending on size. Reliance allows for individual circuit activation. Not sure how the GE works.
 
  #17  
Old 03-27-14, 03:38 PM
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For all those reading on those, is a 12x6x4 Pull Box ROOMY enough for twenty 12AWG splices as well as 2 10AWG going through it.

Or will I be much happier with the 12x8x4D Pull Box.
 
  #18  
Old 04-03-14, 12:25 PM
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Splice Box I ordered from the supply house arrived.
Picked it up and started doing some rough layout...

Started by removing the Squeeze Connector off the transfer switch.
I'm a stickler for these things but I had to post. It was a Bridgeport 1" Right Angle Squeeze Connector. THUMBS up to Reliance for using quality fittings !

I myself go of my way for the following

Raco Steel Boxes
Southwire Wire
Carol Cord
Hubbell Connectors
Bridgeport, T&B and Arlington Fittings
and the list goes on....

They could have easily used a inferior offshore squeeze connector on it but it uses a PREMIUM fitting. You don't see this much in this day and age !
 
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