Help! How Many "Safe/Approved" circuits in this 20 Space Panel?

[Elton Noway]

There is no minimum height for a panel, just maximum height of breaker (6'7"). So you could mount new panel lower and upside-down is fine for most - especially a main lug without main breaker. What is on the other side of the wall? As is a laundry room you have the luxury of being able to remove some drywall. If you also remove from adjacent stud bays you should be able to reroute cables and minimize splices.

Yep thanks... I marked the wall a couple of days ago to indicate maximum for the highest breaker. Guess it looks like the new panel will be going in upside down.

Funny you should mention removing drywall to simplify the project... I did that very thing 13 years ago. As a result, it's also the very thing that's giving me headaches. We had a unused wall off the kitchen I built a coffee bar with wine cooler. (espresso machine for me...wine cooler for the wife) Anyway... I wanted the wine cooler to be flush with the front of the cabinets I was going to install to give it a custom look. To pull it off the plan was to remove a section of drywall behind the wine cooler location so it could slide the cooler back another 4 inches into the recess created by the cavity between the studs. I knew the sub panel wiring might be a problem. As feared... some of the wires feeding up to the sub panel were in the way. With the drywall out I preceded to disconnect the circuits that were in the way and pulled the offending wires down into the crawl space, cut new holes in the floor and rerouted them up and around the cavity and back into the box. Some wires ended up being pretty short so placed those breakers in the spaces nearest the bottom of the panel. As it was I had to splice two circuits . Hence there is no slack left to work with. Also... if you look at the coffee bar you will see and outlet and a wall switch just below the location of the panel which is why I could only move it down an inch and a half if I'm lucky.

Guess I'll be cutting some drywall tonight.

 

[WorthFlorida]

The panel shown above is a 100 amp rating since aluminum wire is feeding it from the main panel, plus you stated that it is a 100 amp breaker at the main. You cannot overload this panel until you exceed 100 amps and the breaker will trip. It is doubtful that if you had everything turned on that it would exceed the 100 amp rating. What is import here is that the two buss bars that these breakers snap into is good. Replacing it with a panel that has 40 or even 60 slots up to 200 amps it will not matter, it can only do no more than a 100 amp load because of the breaker at the main.

I would replace it with a larger one so you have plenty of room and space plus is would put less stress on the buss. A rare occurrence with so many double or tandem breakers is heat. Any time there is a set of contacts or switch, heat is generated. If one of these breakers is constantly operated at near capacity, heat from that breaker will rise and possible trip the breaker above it. All breakers trip on heat. It is rare but I did have it happen at a co-workers home but the panel was of old and no longer would pass UL approval, so the entire panel was changed out.

 

[Sponsor]

 

[Elton Noway]

The panel shown above is a 100 amp rating since aluminum wire is feeding it from the main panel, plus you stated that it is a 100 amp breaker at the main. You cannot overload this panel until you exceed 100 amps and the breaker will trip. It is doubtful that if you had everything turned on that it would exceed the 100 amp rating. What is import here is that the two buss bars that these breakers snap into is good. Replacing it with a panel that has 40 or even 60 slots up to 200 amps it will not matter, it can only do no more than a 100 amp load because of the breaker at the main.
I would replace it with a larger one so you have plenty of room and space plus is would put less stress on the buss. [snip]

True enough. And further proving your point is the main breaker has "never" tripped in the last 23 years with the sub panel as configured. Knowing this, I realize (from an load standpoint) there is no reason to replace the sub panel with one that is rated with higher amperage and/or rated for more circuits. The problem is I need to and another circuit for the split AC unit and the panel has no space left. Yes, I could swap out a couple more single circuit breakers and replace them with a tandem and I'd be good to go... but someday this house will need to be inspected. If the inspector is worth his salt the sub panel should fail inspection. For that reason, as you suggested, the panel will be replaced. (still searching for the "shortest" - 14.5" wide panel. At 29" to 30" " tall these are currently in the running

http://www.homedepot.com/p/Siemens-...WireGuide-Load-Center-P3060L1125ACU/207158486
http://www.homedepot.com/p/Siemens-...-WireGuide-Load-Center-S3060L1125AG/207158525
http://www.homedepot.com/p/Eaton-20...s-BR3040L200V2/100572180?keyword=BR3040L200V2
http://www.homedepot.com/p/Siemens-...1200AG/207161078?keyword=Siemens+S3060L1200AG

I know many members here are fans of a "Copper bus" ( insert the sound of angels singing here)... but at this point the height of the panel and flexibility to fit my current situation will win out.... even if it ends up being an aluminum bus [gasp].

 

[Jadnashua]

Most people are not aware that aluminum 'rusts' almost immediately once it is exposed to air. It isn't noticed like it would be with iron for two reasons: the 'rust' is essentially clear and it is about the same volume, thus doesn't crust up like iron which exposes more elemental iron to further rust. But, the AlO2 is an insulator, thus the need for the special handling. If not done right, it leads to heat and potentially even fires. One reason why Al wire isn't as common (it came into use during a big price spike for copper and is still used for large conductors for the weight savings, but not much in smaller gauges). For that reason, it's not a particularly great material for wiring in a home.

 

[WorthFlorida]

I looked up the Siemens Load Center panels to be sure of the title on the HD site. It reads 30 space 60 circuits. Google "Siemens load center catalog" and you'll see PFD file containing Sect-01-001-016.pdf. The first two you listed Siemens panels are rated for a full load of double or tandem breakers. I did not look up the others.

Siemens catalog:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwi3jqfq1sXSAhXLKCYKHdcDDpgQFgg6MAE&url=https://w3.usa.siemens.com/powerdistribution/us/en/speedfax-product-catalog/Documents/SF-11-Sect-01-001-016.pdf&usg=AFQjCNGrRUCAD4f01ZErOY4sW5epK5GoVQ&sig2=ZIfj5Lgj4tiefmQ31EHyHQ

 

[Stuff]

An aluminum bus panel is fine. If not the fire departments would have outlawed them. After all, the National Electric Code is produced by the National Fire Protection Association.

Some just want to see copper in their panels. Others go with tin plated copper because copper corrodes too much in lots of environments. Well, the thing is most aluminum bus panels are tin plated to not "rust" as mentioned above. Maybe the tin plating is stronger/thicker when it is applied to copper?

 

[Elton Noway]

Most people are not aware that aluminum 'rusts' almost immediately once it is exposed to air. It isn't noticed like it would be with iron for two reasons: the 'rust' is essentially clear and it is about the same volume, thus doesn't crust up like iron which exposes more elemental iron to further rust.

Just to clarify for any newbies or non-techies reading this thread.... to say aluminum "rusts" is a little misleading and might confuse some people. Technically speaking the correct terminology would be to say aluminum "corrodes". Rust is a type of corrosion that is specific to the oxidation of iron or steel caused by any interaction with moisture. Aluminum doesn’t contain iron or steel so it doesn’t rust, however... like steel it corrodes when exposed to moisture and air. The corrosion that forms on the surface, when severe, appears as a white powder and is referred to as oxidation.

I looked up the Siemens Load Center panels to be sure of the title on the HD site. It reads 30 space 60 circuits. Google "Siemens load center catalog" and you'll see PFD file containing Sect-01-001-016.pdf. The first two you listed Siemens panels are rated for a full load of double or tandem breakers. I did not look up the others.

Yep, I also found the wire drawings for those boxes on the site. Any of those panels would have fit the bill, and I'll admit to being partial to those with the copper bus... but, as it turns out "none" of them were in stock at any of the Home Depots or Lowes in my area! I could have ordered them online but the best delivery date was March 15th and I can't loose that much time. I ended up ordering one off Amazon and got it yesterday. As much as some may not like to hear it... I ended up getting a Square D 125 Amp 24/48 Homeline version. I was shooting for a QO version but they don't offer a 125 Amp Main Lug with in 24/48 configuration. I'm aware the Homeline version has its share of haters... but the price was right, I got it right away, it fits the bill, breakers are readily available at any big box store, and it matches the manufacturer of my main feed panel.

The day I found it on Amazon they had 9 in stock, I figured no sweat... I can continue researching panels. Later that evening they only had 7... the very next morning they only had 5! I panicked and pulled the plug. I just checked, now they only have 2. I guess I'm not the only one crazy enough to give the Homeline series a try.

An aluminum bus panel is fine. If not the fire departments would have outlawed them. After all, the National Electric Code is produced by the National Fire Protection Association.

Some just want to see copper in their panels. Others go with tin plated copper because copper corrodes too much in lots of environments. Well, the thing is most aluminum bus panels are tin plated to not "rust" as mentioned above. Maybe the tin plating is stronger/thicker when it is applied to copper?

I'll admit I'm old school and would have liked to have seen copper in my panel... ( probably because I was burnt decades ago when I purchased a house with aluminum wiring. Ugh!) Although I'm not a proponent of aluminum and electricity its hard to escape the fact that the majority of load centers and panels on the market have aluminum buses and they are offered by all the leading panel manufacturers. Like you say... if they were really a fire hazard they would have been off the market a long time ago. This new one I purchased has a tin plated aluminum bus bar and 10 year warranty so I'm happy as I can be under the circumstances.

 

[Jbfan74]

Okay... thanks to everyone's help I think I've pretty netted the conclusion:
Right or wrong... My sub panel was an "old enough" design which allowed the current mishmash of too many breakers, of various styles, both single and tandem. As a result the panel contains more circuits than it was designed for or rated to handle ... too many single-pole/one circuit breakers have been replaced with tandem breakers and would currently be considered in violation (grandfathered or not). So... I need to replace the panel!

My next dilemma is the existing sub panel is only 16" tall, having a bottom feed with the wires routed to the top of the bus bars. All the new panels (125 or 200A with a minimum of 30 spaces) are 30" tall at a minimum! While the new box can be mounted higher, for a number of reasons I can't move the panel any lower than it is now. So... it appears the feeds won't be long enough to reach the bus on the top of bus in a new panel. I was thinking I could flip the panel over with the bus connections at the bottom but that doesn't seem to the the standard. Also, due to the current layout with the neutral bar at the bottom most all of the neutrals are cut short. I've already concluded I'm going to have to splice quite a few neutrals in the new panel. Let me know if I'm on the right track or there's a better solution/suggestion. NOTE: I know I could gut the existing panel and use it as a junction box, and mount the new panel to the side but that's not something I want to do in the laundry / utility room. (for me... it would look too hodgepodge.. and I don't want the house to appear any older than it already is)

Put in the taller panel and you can splice to the existing wires to reach the bus, or you can install the panel "upside down"

 

[Jadnashua]

When iron rusts, it incorporates oxygen into it's new chemical structure. The same thing happens to aluminum. A better, more generic term is oxidizes...both do, but aluminum's oxidation is much more prevalent. The only reason aluminum doesn't oxidize to nothing like an iron compound can, is that the oxide of aluminum is quite strong and functionally the same relative volume unlike iron oxide (rust), where the oxide is larger, thus tenting up on the surface, exposing more elemental metal to the process...that oxidation of aluminum acts more like a preservative, but it isn't anywhere near as conductive as the elemental material. Thermal expansion/contraction can cause movement, which can expose the contacts to becoming oxidized. Connections to aluminum generally require the proper tools when crimping or torqueing fasteners down and, often, an antioxidant paste to prevent it oxidizing. Failing to treat the connections properly can lead to problems. Just like most things, it requires some knowledge and good practices to be reliable...probably more so than making a connection with copper. Either can work...aluminum tends to be cheaper, and will work, if you follow the rules.

 

[Elton Noway]

Put in the taller panel and you can splice to the existing wires to reach the bus, or you can install the panel "upside down"

Done!... Installed a taller 125A panel. Granted the Homeline products aren't real popular among the professionals in this forum but it served my purpose. The Square D HOM2448L had enough room and circuits to accommodate all my existing circuits with 6 to spare. Even installed upside down many of the circuits would still be too short. But, upside down was my only option because the main feeds wern't long enough either. To keep the installation clean, rather than using wire nuts or gamble on "crimp" connectors I chose Spliceline - Crimp Free- Push-In Butt Spices since they are a snap to install and don't clutter the box.

 

[Stuff]

Looks good. Nice and neat, especially impressive for that many circuits in a panel. You should put some tape on the white wires going to the two pole breakers to "re-identify" them.

Those butt-splices are a nice solution.