Why are transfer switches so expensive? What's wrong with
Using a 3-way switch for each circuit that I want to connect
To my generator?
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Why are transfer switches so expensive? What's wrong with
Using a 3-way switch for each circuit that I want to connect
To my generator?
I am looking for an easy way out too. The 3 way switch should work, but leave you with no circuit breaker protecting the wiring. Yeah, you could set up another circuit breaker box, but again you rigged it, you could have most of what doing it right would have cost and be breaking code. I have seen sub panels with a double throw switch for $60-$80. If I don't find a better solution soon, I may go that route. I already had to put some half size breakers in my 20 breaker 100 amp box. I would be delighted if somebody posts a better idea.
I fell into a deal on a Coleman 6250 watt generator. To use it legally, it would cost more to pay an electrician to wire in a transfer switch. I am rather bold on DIY projects and have little hassle from the inspectors. But think I will skip that one.
At the load end there is nothing wrong with a three way switch (as long as ratings are matched). You require an additional steps to disconnect generator power from the utility power and vice versa.
However, if you forget to throw a switch though and connect your generator to the utility- buy, buy generator. A circuit breaker will not operate fast enough to lower the interrupting current (the generator's windings will look like a short circuit) and the insulation on the generator's windings will fault.
Using a three way switch is "thinking outside the box", since a 3 way switch really is a single pole double (TYPO CORRECTION** pole**) throw switch, however, as labman mentions, does not offer overcurrent and short circuit protection of a circuit breaker for the generator power side of the switch.
Depending on the quantity of branch circuits you want to power, consider something similar to a Gen-Tran switch found at the following link:
http://www.gen-tran.com/eshop/10Brow...tegory=MTS6-10
You will find several units that can handle from 1-10 circuits, and each switch is a SPDT switch and circuit breaker, all built in one unit, alnong with the generator power inlet.
I am not sure what bhayne means by "additional steps to disconnect generator power from the utility power and vice versa."
, as a three way switch works exactly like a real transfer switch, it is in either one position or the other, and the gen power cannot be connected to the utility power.
Again, thou, you will not have any protection of the generator power if any circuit using a 3 way switch, if a short or an overload occurs the generator will continue to deliver power until one of two things happen, the short or overload burns the brach circuit wiring or the genset will fail.
Therefore, your solution of just using a 3 way switch is not allowed. As you can see for about $200-300, plus installation of about 2 hours, you have a perfectly safe and easy to operate system.
OK, I messed up. But at least I admit it! I doubt that these transfer switches are retrofit and I look very closely at retro-fit installations involving service entry equipment- especially when it involves older houses. I'm sure that I'm not the only one (which is why your probably looking at 3-way switches as a simpler alternative in the first place).
The installation that I was referring about was a genset connected to panel breakers. During utility operation the breakers are open. During Generator operation the breakers are closed but the main breaker is open. This satisfies code requirements (breakers are not unidirectional) but requires additional operations to isolate the generator from the utility. If both are connected, the breaker(s) will protect the generator supply conductor but may not protect the generator's windings.
Actually, after reading the manual to the above transfer switch, it is very similar to my idea except my idea does without the expense of a new box and all that wiring!
Bhanye, why would you not allow a UL Listed ,prepackaged unit, made by GenTran, a division of Reliance/Rockwell Automation, a premiere electrical manufacturer, as is Reliance?
Instead of a simple unit, made specifically for retrofit in any age installation, the installation consisting of a few mounting screws and a two wirenuts per circuit to splice into the existing branch circuit, you recommend a homemade contraption with , at least 3 connections for each circuit, plus the splices, and no method of overcurrent and short circuit protection.
Your statements of being a strict inspector are contradictory to your advice.
I sure hope people don't take this advice and start creating their own "transfer switches" in this manner.
Again, astounding.
Whatever you can afford!
Just goes to show that you don't have to be rich to be safe. Actually, Rockwell Automation and Reliance tend to use other namebrand equipment, put their stamp on it and give it a hefty markup. They are the last place I'd look for a residential installation!
Simple answer guys! Gen-Tran Transfer switch or the new ones by Reliance. Easy cheap and best of all safe!
Look on eBay or craigs list I just sold a 6 circuit for $150.00
VERY EASY TO INSTALL AND COMES WITH INSTALL DIRECTIONS
Thank you for your responses. I have a special situation that makes it impossible to install a Gen-Tran switch. I have no main disconnect. That's right. No main disconnect. The house was built in 1952. It has an FPE main lug panel with four 15 amp 115v circuits and one 20 amp 115v circuit. All circuits are protected by Stab-Lok circuit breakers.
In 1963 a central air conditioner was installed. Two black wires run from the hot bus bars in the panel to a disconnect switch installed just outside the panel. The disconnect switch has two 30 amp cartridge fuses -- one for each black wire. There is a similar disconnect switch on the compressor outside.
All the house wiring is inside metal conduit. I don't know if it is rigid or EMT.
My main concern about a 3-way switch is the fact that I would be running a whole circuit through that switch for many years to come. My only experience with a 3-way switch is turning a light on or off.
How good are the contacts in a 3-way switch? I've seen diagrams of a DPDT transfer switch and it looks something like the disconnect switch on my central air conditioner. Really secure contacts. I've never seen the inside of a 3-way switch and I wonder about the contacts and the chances of arcing.
As for protecting the cicuits when I'm on generator power, the generator has two 115v receptacles, each protected by a 20 amp fuse. The only motors I would be running are the furnace blower on continuous operation and the refrigerator, which would cycle on and off. The refrigerator is on the 20 amp circuit so no worry there. The furnace blower is on a 15 amp circuit but it runs continuously. Everything else would be lights, TV, and the computer. That's all. I wouldn't run the microwave, dishwasher, toaster, or washing machine while I was on generator power. I have gas heat, stove, and hot water.
What was and still is allowed for a Main Disconnecting Means is called the "Six Switch Rule", which appears is what was applied to your service. So, you still have only six switches to shut off the main power to the entire home, and your service is still in compliance.
Keep in mind, any additional branch circuits will cause your service to not be in compliance with NEC and local codes.
So what is the problem? Why is installing a 4 or 6 circuit GenTran impossible? All A GenTran does is intercept the branch circuits, which in your situation are also acting as main switches.
Three way switches are available in 15 amp and 20 amp ratings, and are available in different grades similar to light,medium, and heavy duty, that may be listed for resistance and/or inductive loads. If being used for anything besides incandescent lamps, they need to be rated for inductive loads.
Thou I am furnishing the information you are asking for, I am not recommending you build your own "transfer switch assembly", and would rather you install a UL Listed assembly, that is easy to install, will work reliably and safely.
You have been given two points of view to decide on, the final decision is all up to you.
Thanks, tkrussell! I never heard of the "Six Switch Rule." I'm surprised, though, that it's allowed. The bus bars are always hot. Is it OK to remove and install circuit breakers with the bus bars hot? As I understand a Gen-Tran switch, it's essentially a sub-panel. So I would have to install a circuit breaker in the main panel to feed the Gen-Tran switch. I can do this with the bus bars hot? Also, are Stab-Lok circuit breakers even available?
Can I high jack this thread? I am really getting serious about the Gen-Tran or other similar panels. I have a 1970 GE 100 amp panel that takes TOQ, TOL, etc. breakers. It is mounted on the back wall of my garage. Where can I locate sub panel? Does code give minimum and maximum heights? What about mounting it sideways? Most of my essential circuits go down and over to the crawl space. If the subpanel was mounted below the main panel, you could connect most of the essential ones without splicing. Can you splice wires in the main panel? Will the existing single buss for ground and neutral be a problem?
Yes, it is possible to remove and install breakers while the bars are hot, just need extra caution. But, look at the product I furnished below, and you will see that removing breakers or trying to find FPE StabLok breakers will not be necessary.
Yes, FPE breakers are still available for replacements, marketed by American Breaker. FPE had some issues years ago and, no longer makes StabLok panels.
Are you sure there is not a main breaker at the meter location? May not be one there, just had to ask.
Yes the six switch rule is still allowed, I recently did a 3000 amp 277/480 volt 3 Phase service for a manufacturing plant using this rule. The switchboard came rated for "Service Entrance Equipment with Six Switches" and with only six breaker slots. Sure someone can come along and add another breaker, but once that happens, a 3000 amp main switch is required.
Take a look at this webpage, and download the instruction manual:
http://reliancecontrols.com/ProductDetail.aspx?15114A
A closer look at GenTran, I see they want a main breaker, and the Reliance I provided is what use to be GenTran system that I am familiar with.
The Reliance Model # 15114A is a four circuit, with a SPDT switch and circuit breaker for each circuit. Simply shutoff each circuit, remove the branch circuit wire, splice onto the load side wire from the transfer switch, connect the line side from the TS to the breaker in you panel, do this for all four circuits. Be sure the transfer switches are all in "Utility" mode, and turn on the breakers in your panel. Done.
As always, be very careful working in a live panel.
Quote:
Originally Posted by labman
Sure can, it is now public domain, so have at it.
GE THQL breakers will fit the same as the existing breakers, and will not void any UL listing.
Disconnect switches and breakers should be no higher than 6.5 feet to the top handle. No minimum on lower, just need to use common sense, like protection from physical damage and water spray, don't mount so low that snow will bury it, things like that.
Sure, sideways is not a problem, looks a little weird, but electricity does not care. No specific code exists to worry about.
Splicing branch circuits in the panel they are supplied from is allowed. These types of transfer switches rely on this practice for easy installation.
The equipment ground and neutral from the generator will connect to the main panel's neutral bar, and separated if applicable.
A transfer switch is a "three way switch" and would require the same degree of expertise to install, I do believe that by removing your fuse you are disconecting service to the circuits needed to operate and at the same time a Gen-Tran has an "off" position giving a disconnect.
I'm a living witness!Quote:
Originally Posted by tkrussell
This last post by ceilingfanrepair has got me worried. I guess I really should replace the FPE panel as soon as possible. Shoot. Do you know what that means? The FPE panel is rated at 70 amps. So I'll have to upgrade my service. Which means that I might as well go to 200 amps. That means a new meter box, probably larger conduit to the new panel. I might as well have a disconnect switch outside. And maybe put the wires to the house underground. How much would all of this cost, excluding the underground wires?
Thanks for all the info, tkrussell. I didn't know that it's considered proper to do that stuff with the bus bars still hot. Pretty scary, though. The Pro/Tran model 30216A rated at 7500 watts would be perfect for my situation: http://reliancecontrols.com/ProductDetail.aspx?30216A
But it looks like the FPE panel has to go. That being the case, should I still go with the same transfer switch?
Don't take my word for it, see what TK has to say.
I'll take your word for it.HTML Code:Dont take my word for it, see what TK has to say.
TK just said that FPE had some issues with the Stab-Lok breakers. I figured that the fears were mainly fueled by alarmists, otherwise TK would have said something more forceful. But I did more research and now I'm more concerned.
I think that it's mainly a problem with the double pole breakers. One breaker will get hot and the other breaker will prevent it from tripping. I don't have any of those.
But it's an old, poorly designed panel with breakers that are 54 years old. I'll feel a lot better once it's replaced.
Well I had a single-pole 15 amp breaker that didn't trip with a dead short, instead it just sat there shooting sparks. Plenty of the other breakers worked fine and tripped with a short or an overload so.. .
Like you said, I figured if your FPE really needed to be replaced, TK would have said something. But personally I won't let another one in my house!
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