Installing a Generator Transfer Switch, Part 3: Wiring in the main

Almost there...

In order for this panel to act as a sub-panel, it has to get power from the main panel.  Because I ordered the TRC0603C, where the 06 means it has a 60amp breaker coming in from the main, I also had to install a 60 amp breaker in my main panel.  This also means I had to adequately size the wire from the main breaker to the sub-panel...

The feed wire...

According to the National Electric Code (NEC from here on out) 2008 Handbook, 6 ga wire should be large enough to handle the 30amps of current.  I went to Lowes and looked at their wire current and pricing page, which said it was only good for 55amps... after speaking with the sales associate there, they referred to a page copied from the NEC and agreed that I was safe.  My electrician here at work agreed with me, especially since I'm only going 6ft.  These guys also agree with my decision... hmm, they have a good bit of good articles!  I suggest you check it out.

The end of the wire...

Wiring it up...

With my wire ready to go, I first had to pick the cable clamp size I thought would work best for the wire I was working with.  I didn't find any great guides for choosing a size, but I decided to go with 3/4" clamps.  Next I had to remove the knock out in the sub-panel and the main panel.   

I highly recommend you turn off the main breaker before you remove the cover or  do any work in your main panel!  This will ensure you ALMOST can't electrocute yourself.  (Same thing applies once the sub-panel is hooked up).  Always check to make sure the wires or equipment you are working with are not energized! 

The main panel with the cover removed.  Seriously, don't touch the stuff circled in red, it can still shock you!

NOTE: If you want to wire in the sub-panel first, you can work with the main panel still energized... that way you can still turn on the lights to see what you are doing.  But remember, this is assuming you are not in the main panel, your generator is not feeding the sub-panel and the feed wire has not been hooked up to the main panel yet!

NOTE: Always kill the breaker feeding your feed wire to the sub-panel and unplug your generator before thinking about working on the sub-panel!

With the knock-out's removed and the cable clamps installed, I next had to feed the wire into the panel to get an estimate on how much I'll need to strip back the insulation.  Hint: Leave yourself a few extra inches!  Stripping the insulation works the same as it did when I wrote Installing a Generator Transfer Switch, Part 2: The Generator Feed Wire.  I like to use a Sharpie marker to mark the location on the insulation to strip it back to.

The TRC0603C Sub-panel.  EDIT: Those are POWER meters, not current.

REVIEW: Red and Black wires go to the breaker.  White goes to Neutral and the bare copper wire goes to ground.


With the main insulation stripped back, I put the wire back through the cable clamp and tightened it down.  From there, I routed the wire through the sub-panel to get an idea of how long each wire needed to be.  Trim all the wires to whatever length you desire and then trim the insulation back about an inch.  Give the bare wires a nice coating of the ox-guard (corrosion inhibitor) and clamp them down.

NOTE: In this instance, I clamped the Neutral (White) wire down using the main lug.  In the picture above, on the left hand neutral bar at the bottom is a hex nut.  I backed this out, put the wire in, and torqued the nut down.

The line-power feeding into the breaker, coming in from the bottom

You can see above that the red and black lines go to the breaker while the bare copper wire goes to the ground.  I already mentioned white going to neutral.  Also shown is the first circuit being run.  This one is going up to a terminal box where I'm splicing in a wire that isn't quite long enough to make the switch from the main panel to the new sub-panel.

But you can also see for this new circuit that black goes to the breaker, the white goes to the neutral bar and the bare copper wire goes to ground, just like in the main panel.  This is repeated for each circuit being wired.

Making progress...

One thing that I did, that I thought was a good idea, is use some wire labels I pulled out of the trash while working at a previous employer.  They would print labels and if the printer screwed up, they'd trash the whole batch.  Some of them never got printed... so I'm using a permanent marker to label my circuits and heat shrink the labels onto the wires.  This way if I ever need to go back and figure things out, it should be easier to do!

Heat shrinking a wire label... it's hard to do AND take a picture!

Everything was going along just great until I ran into some wires coming down from upstairs... they wouldn't reach my new box.  So after two trips to the hardware store, I ended up installing two junction boxes to fit all of my wire junctions inside, seen below.

The first junction box

These boxes are necessary any time you need to splice two wires together.  In this case, the upstairs bathrooms and bedrooms wouldn't reach in addition to a few from the main level, so there were a few splices to make.

Be sure to use the correct size wire nuts!

I learned a few things about junctions after I finished this up.  You don't need wire nuts on the ground wires... just take all of the ground wires and leave about 5inches extra length and twist them all together.  That could possibly save some money.  I also learned you can put as many wire splices into a box as you can safely fit... so don't splice off too much shielding, you want them inside the wire nut so they don't short out to another wire when you pack them in there like sardines!  You can read my previously article on splicing wires here: How to strip/splice wire.

The final product

THE INSPECTION...

So there you have it, the inspector came last night.  I passed my inspection with flying colors!

The only issue was that I had previously made a knee-jerk decision to use different wiring after everything was up and running and when the electrician came, he helped me put it back to how it had been done previously.  Everything worked awesome and now we are ready for A storm.

Notice I did not say "THE STORM"!

I don't think "THE STORM" will ever come, but little by little, day after day, eventually there will be a storm.  Now I'm a little bit more prepared for when a storm hits. 

Can you "Sleep when the wind blows"? (That was the first place I fount it posted, cant remember where I first heard it.)

The electrician comes tonight!

Okay, tonight I will find out just how great or horrible I am at playing "electrician."  At a rate of $60/hr, I sure hope I am pretty good at it!  I'll post more on wiring it up after I get the go-ahead from the electrician...

Don't get your wires in a knot...

When I started in on my main circuit breaker panel, there were a lot of breakers with two wires coming off of them.  Probably not a big deal... but I either got lucky or God was watching out for me!  But let's back up for a second...

I started out this project flipping breakers and figuring out what it turned off in my house.  It all went fine till I flipped one and couldn't figure it out... actually, there might have been three of those.  No big deal, I'll figure it out later... right?  Well as I've been swapping wires over from one panel to the next, it opened up breakers in the main.  Then I'd take the doubled up wires and spread them out, so they no longer share a breaker.  During this time, I don't think I ever moved two special wires, but I did discover that when one wire was energized, the other one was too!  It got to one point where I had to flip BOTH breakers in order to turn off the lights in the basement... hmmm... why?

This weekend my neighbor came over to help me trouble shoot the wires... my wife caught me with the drywall saw about to attack the problem and told me to call the electrician.

What kind of self respecting man calls a professional before exhausting all other options?
That's an easy one...                             THIS ONE!

So my neighbor came over, talked me into putting down the drywall saw and started walking through the problem with me.  In the process, as I was about to pull the two wires off one breaker and put one on another, he suggested I stop... as in DON'T DO THAT!

As I pointed out before, when one wire is in a circuit turned on, the lights are on.  I should also mention that the other wire is hot at this point, indicating that the two wires are connected somehow.  I proved this with my volt-meter by testing for voltage from the wire to the ground terminal... yep, 125 volts!

Now the reason I shouldn't put that other wire into a second breaker is that I would then risk putting it into the other leg of the power coming into the house... this would create a 240volt circuit instead of 120volts... a very potentially dangerously risky thing to do in terms of burning down your house... those light's are not designed to take 240volts!

Well we eventually narrowed it down to some 3 way switches and a switch box with all of the black (hot or energized) wires tied in together in a single red wire nut... well there were two wires that shouldn't have been tied in together and when we pulled them apart, everything worked just as it should.

So now I can wire my living room into the sub-panel without any worries...

Why not just leave them on one breaker?

The problem is that I wanted to only wire up the living room to the sub-panel.  If I had done this without correcting this problem, when operating on generator power, I would have ended up with one wire coming out of my sub-panel that fed power back into my main panel and hence, back out to the power lines the line-men are trying to repair... defeating the whole point!  It was a stupid mistake by whomever wired up the house, but I'm glad we got it fixed...

Besides, if I had called the electrician, I'd be out money, pride and the knowledge I gained from this experience... and knowledge is one thing that can't be taken away from you.

With that, have a good one!

 

Hehe...

Installing a Generator Transfer Switch, Part 2: The Generator Feed Wire

The sub-panel

The TRC0603C

As you can see above, I've labeled all of the main components of the panel.  This unit comes (assuming you do not buy the pre-wired version) with only two breakers installed, that happen to have some hardware attached that prevents them both from being turned on at the same time; hence the transfer switch.  The line power breaker will be hooked up to the line power side and the generator power breaker will be, of course, hooked up to the generator.  Only one of these can be turned on at once, preventing you from back feeding the lines outside your house. 

 

Getting started...

Everything up to this point has been the same as if I were installing an every-day sup panel.  This is the part that makes it a Generator Transfer Switch!  The first thing that I have already established in part two of my Generator Transfer Switch series is that my generator can provide 30amps at 240volts AC (alternating current).  I also covered there that this much current requires a 10ga, 3 strand wire with a ground wire.  I’ve also mentioned that the previous owners of my house had a hot tub in the room furthest from the main breaker.  Luckily, it was a 10ga 3 strand wire... Woohoo!

This is the bundle of 10-3 wire previous owners left behind and ready for me to use!

After I pulled the wire out and bundled it up for storage, I got to reverse this as it came time to hook it up to the sub-panel.  After coming up with a plan as to how I was going to route the generator feed cable from the sub-panel to the power inlet box, I spent a lot of time with the hole-saw putting holes in my joists so I could avoid using the staple nails... hopefully that will pay off if I ever decide to finish off the basement ceiling.  

Here’s the wire clamp I used.  I believe it is a 1” clamp (my understanding is that dimension indicated the size of the hole in the sub-panel).

Installing a cable clamp required me to first remove the knock-out on the top of the box.  Make sure the clamp you have ready matches the size of the knockout you select!  To remove the knock-out I took a flat head screw driver, placed it over the knock-out (see image below), right next to the edge, and smacked the top of your screw driver with a hammer.  Then I used a pliers to bend it back and forth till it snapped off.  There might be a better way, but that worked for me just fine.

Once the knock-out was removed, shown in the next picture, I installed the cable clamp.  One installed, I fed the cable through the top of the framing (I’m sure there’s a technical term for this, feel free to comment) and fed it through the cable clamp after cutting back the outer Nomex (or whatever the outermost plastic wire insulation is called) to the point where the insulation just comes through the clamp, protecting the inner wire insulation from getting cut or nicked.

The generator feed wire insulation stripped back and ready to thread in through the clamp.

With the insulation stripped back and the wire clamped in place, I was then able to wire the feed cable into the sub-panel and start wiring it in.  Reliance did provide some guidance on how to install the sub-panel (here) and the power inlet box (here) that helped me to understand everything I was doing... of course Lance, the electrician at work gave me a lot of good advice too, like using the oxidation blocker.  When I got into it, I didn’t know that white was always neutral, but figured it out after reading through the instructions for the power inlet box.

While goes to neutral, red and black are hot, and the ground goes to the grounding terminal block.

One item I should point out a this point is the oxidation blocker.  Have you ever had corrosion on the battery terminals of your car?  That's the same thing that can happen to your wires at each connection.  Your batteries suffer from this more as a result of diss-similar metals in contact with each other resulting in Galvanic Corrosion, but the same basic concept can happen when you make connections in your home wiring.  I used a product I picked up at the local hardware store...

This little tube of slick black goop should keep my connections clean and free!

Applying the oxidation blocker to a neutral wire.

To open this tube of wonder, you have to cut off a portion of the end of the tip.  I cut it as close to the end to make the hole at the end very small... and later trimmed off a bit more.  To coat the end of the wire, I stick it inside the tube and squeeze the tube as I pull the wire out, leaving a thick (but not too thick) coating of goop (most likely called grease).

The other end of the wire...

What you’ve seen so far was definitely the easy part.  The next decision that needed to be made was where I was going to put the power inlet box.  I was thinking I'd put it just below the siding, attaching to the cinder blocks so the wire would come in through the back... before it snowed.  You might not be able to tell, but that snow in the corner is about 30inhes deep.

Once I saw the prospective location in the snow, I had to change the inlet box location.

After looking at the above picture, I don’t want the inlet box to be under 2ft of snow on a regular basis.  I know the inlet box is supposed to shed water from the elements, but somehow it didn’t seem like a good plan.  Therefore my father suggested I cut a hole in the vinyl siding, mount the power inlet box in the hole, and then trim it out.  This seemed like a good idea so I pulled out my new extra long masonry drill bit and away I went! A couple notes on this... I wanted to make sure I drilled through one of the hollow sections of the cinder block, hence the hole is located about 25% of the distance from one end.  The extra long bit allowed me to make a guide hole on both the inside and outside, as my 5/8in bit (just large enough for the wire) was not long enough to go through the entire block from outside.  Ready, Set, GO!

The extra long bit was to allow me to drill all the way through, providing a guide on the back side for the larger, shorter bit.

Ready... set... Stop.  So dead batteries have a way of changing your plans.  Thankfully, my father brought his hammer drill.  My drill has a hand chuck, so I don't have any chuck keys.  Dad's drill didn’t and he didn't bring one.  Needless to say, it required a little ingenuity to get the drill bit tight... without the chuck key.

When working with pipe wrenches, it’s always nice to have two of them!  (I can’t think of a time when one would be good enough).

With everything in place I drilled larger 5/8in holes on the inside and outside of the cinder block and threaded the wire through.

Inside my crawl space I had to work around some piping...

This is another time you should consider measuring twice and cutting, or in this case drilling, once.  Inside the crawl space I had a wonderfully installed Radon Mitigation System... my hole was just barely high enough that I was able to work around it.  It sure could have gone worse! 



Now that I have a bare wire sticking out a hole in my foundation and going 3ft up to a power inlet box for my generator, I have a problem... what if some little boy with a weed eater one day wonders what will happen if he attacks that wire with it?  What if some little boys want to try out their pocket knife on it?  What if blah blah blah...  The answer is Conduit.  It is designed to protect electric wires from little boys, weed eaters, pocket knives and more.  In a following post I'll talk to you more about how I assembled all of my conduit.

The power inlet box, trimmed out and everything!  The trim is only held in by friction and the cover/plug is not shown.

Wiring up the box isn't too bad.  I've heard rumors that wiring it up for a 50 amp circuit can be a little challenging as there is not enough room in the box to connect the wiring and then put the cover on.  But for my application, I didn't have any real problems.  Once I pulled the wire through the conduit I stripped the primary insulation back about 5 inches, just long enough that it was still stickup up through the collar on the conduit.  Then I stripped back about a half inch of insulation around the individual wires, or conductors, and inserted them into the back of the cover/plug.  The red and black wires went into the holes labeled X and Y receptively, while the white went into the neutral hole labeled W, and the bare ground wire was attached to the greenish-blue screw in the top right of the box in the picture above.  The back of the plug has another wire that attaches to this screw, so make sure those are both connected!  Again, for each of these connections I applied the oxidation goop.  In this instance, I think it to be even more important than indoors, as in an outdoor environment, there is likely to be more moisture condensing out of the air and settling on the bare wires... causing more corrosion.  I could be wrong, but why take the chance?  The Ox-guard wasn't too much more than $5.

I'll try to remember to take a picture the next time I get the cover off, but you may have to wait till the weather warms up a bit!

Till next time, Enjoy!

Note to self... hurry up with it, you have garden seeds to get started!