Chris...
In looking at the art. on daisychaining, I can see where the "CONTEXT" can lead one to agree that the electrical connection is in parallel. They use the series intrepretation of daisychain to suggest that one has one power consumption device following another following another. From a volts and amps perspective, this is in parallel. But as an electrical engineer, this type of loose talk can put a sand burr under my collar.
As to using peanut breakers. Well, folks, here is the deal. Back during the late 60s and early 70s, many homes were built using 60 to 100 amp service centers with very limited space. Many of these centers were made by federal pacific and your safer off by using a penny in a fuse socket. That is why you dont see federal pacific sold today... the UL and CSL cancelled their ratings for safety issues. Whenever I see a federal pacific box, I am ripping it out before the ink on the contract is dry!
Clearly, there is a use for half size breakers or peanut breakers. Under certain loading conditions, the box is simply smaller than that which is allowable given the disconect breaker and incomming service line. Here a little bit of a good thing goes a long way. Replace all your breakers with half height breakers to double your slot count and you can exceed the allowable number of branch circuits for the given incomming service and disconnect. Also bear in mind that the service center back plane may not be rated for all that extra current draw.
So if you need to add one or two extra branch circuits to an existing installation, you should be more or less O.K. Start adding 220 volt, high amp draw circuits, and you may overwhelm your service center.
I have used these before even though I personally do not like them. My experiences with federal pacific hardware has led me to be very critical of this part of the home electrical installation. My favorate breaker and service center hardware is that of square D. Not the Homeline series but rather the QO and QOB series. I have also had good luck with Siemens.
But if your looking for the top of the line electrical gear, you cannot beat the Square D QOB series. This hardware has many unusul features behind it. First of all, there is no "SERVICE CENTER" or "LOAD CENTER" available in this line. Rather, you need to purchase the panel itself. Also, these panels do not come with integral disconnect breakers. They are by default, sub panels. The boxes are sold separately but if you buy the panel, the box cost is $5 dollars. Whoopieee! This was how crescent electric supply sold me the last three of these that I purchased.
If, for example, your installing a main service center and need a service disconnect, you will purchase the disconnect add on kit and the breaker. This will require you to get a longer box which is not an issue if you buy all three items at one time. The breaker it bolts to the panel thereby extending the length of the panel. That is why the box size varies.
Next, you need to know which type of cover your using. There are two types depending on the finish wall. This will affect how deep the panel needs to be set on its studs. The box contains four studs on which the panel mounts.
The QOB breaker is indentical to the QO breaker with one important exception. The B stands for bolt in. These breakers have a retaining bolt on them that secure them to the panel unlike normal breakers which just snap into place. All QOB breakers work with all QOB panels. The panels can be purchased as either two pole panels or three pole panels. The breakers are available as ONE, TWO or THREE pole breakers. Only the THREE pole breaker must be used in a three pole panel. The other two breakers can be used in either two or three pole panels. For the sharp observers, your right..... three pole panels are used for three phase service hook ups.
Now also note that the three pole panels are more popular than the two pole panels in the particular line up. Thus, it may be cheaper to buy a three pole panel than a corresponding two pole panel.
Because the QOB breaker is a bolt in breaker, there is one other very wird thing you can do with these. You can back feed a breaker! Service disconnect breakers must by code have a solid mechanical retention device. Thus, a snap in breaker would not quality. The QOB breaker does! But these are only made up to 100 amps. If you need more than 100 amps on a service disconnect, you must purchase the dedicated add on disconnect kit and disconnect breaker which I mentioned earlier.
So what is a back fed breaker? If I use a QOB panel setup as a sub panel (i.e. no dedicated disconnect breaker), I can use two slots and a 100 amp QOB breaker to actually add in my service disconnect. The main service input lines are now wired up to the output lugs of the breaker and the breaker works in reverse supplying power to the QOB panel back plane. MAKE SURE YOU APPLY THE MAIN SERVICE DISCONNECT STICKERS TO THIS BREAKER!
For most of us with wood shop issues, this may or may not be of use. But here is one idea that may be of use. Now kiddies, listen up!
If you install one huge hunkin THREE POLE QOB panel in your wood shop, you will be well under way to getting anything and everything running. You can hook up TWO poles of this from either your main service center or from a separate ouside service. If your using your present home's service center to feed this panel, then this is an example of a sub panel. If your using a dedicated external incomming service, then you will need to add the extra add on service disconnect breaker kit (TWO POLE KIT ONLY).
Make sure you wire up L1 and L2 such that you can install ONE and TWO pole breakers using only your incomming service. Leave the L3 buss on its own. Install a 60 amp or less two pole breaker and use this dedicated circuit to run your phase converter. Feed it through a switchable disconnect box to make things easy for now. Throw the switch on the disconnect box and your phase converter comes to life. Now the phase converter has four wires going into it. The green one is a ground. The other two input leads supply power to the converter and these are fed by the afore mentioned double pole breaker circuit. The last wire is the phase converter output line. This wire goes straight into the L3 lug of your three pole QOB load panel. You have now activated the third leg of your three phase system. Any three pole breakers are now able to run woodworking machines like your oliver table saw and newman jointer, etc.
The beauty here is that you can start with one panel. A single pole QOB breaker can run your light circuit or your 110 volt receptacle branch circuit just as before. Then you can add on a two pole breaker to run your single phase unisaw or grizzley planer. Then you can add on a three pole breaker to run your newman jointer or other hunk of old three phase iron.
Should you overload the three phase system, the two pole dedicated circuit that runs the phase converter will trip and take the converter offline. The only issue you need to be aware of here is that the machine tool may now go into single phasing. IT will continue to run but at a huge loss of power and will exhibit some strange behavior and make some wird sounds. Just shut down and let things cool down and reset your converter breaker. My system solves this problem by disconnecting all three phase lines including L1 and L2 upon a loss of any leg including L3. But this requires multiple service panels and is much more complex. What I have just described is hard enough to understand and I dont wish to complicate matters more by describing what I have done. My system has three QOB panels! One is 240 single phase. The second is 240 three phase. The last is 440 three phase.
This is an example of back feeding a phase converter into a single service center. There are a lot of technical issues to consider when doing this and you need to discuss this with your local inspector and have him talk to the engineers at companies like Square D or the phase converter maker. Also note that three pole panels use slots in groups of three. So if I use a single pole breaker, I can actually use a second single pole breaker on the second slot. So I have one breaker on slot 1, a second breaker on slot 2 and slot three is left empty. I DO NOT WISH TO USE THIS SINGLE SLOT FOR NORMAL USE! This is actually a good thing as the two single pole branch circuits work to balance the neutral in the service panel so this is something I actually want to have happen. When I install a two pole breaker, I lose the third slot. So, here I can install a two pole breaker in slot 4 and 5 and slot 6 remains empty and never used. Lastly, I can install a three pole breaker in slot 7, 8 and 9.
Hope this makes some sense and gives you an idea of the power and versatility of using the square D QOB panel system in your home, your shop and your business.
Regards...
Had the dog not stopped to go to the bathroom, he would have caught the rabbit.
Originally Posted by Dev Emch
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