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Help in deciding which transfer switch to buy for genertator

Help in deciding which transfer switch to buy for genertator

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  #1  
Old 06-03-13, 12:10 PM
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Help in deciding which transfer switch to buy for genertator

Hi,

I have a 6500 Watt gas fired portable generator. I bought it last year and now plan to setup it up using a transfer switch. While going through other posts I do realize that if you have GFCI/ AFCI circuit breaker in panel, using a transfer switch for generator can make them trip.

A possible solution to this issue seems to be installing similar breakers in your transfer switch and that way the issue will be taken care of (Need a confirmation on this)

If my above statement is true then I think I should purchase a switch in which I can change the circuit breakers and stay away from something like this. For this I am considering below two given switches. Please let me know which I should go for or any specific experiences you had with any of them.

As a side note - currently I do not have any AFCi in my panel but I am finishing my basement and will need a new circuit. And very much likely inspector is going to ask me to have a AFCI for new circuit so keep that in view considering to install the compatible switch.

Option 1

Option 2
 
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  #2  
Old 06-03-13, 12:57 PM
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All those links are what professionals call transfer panels, not transfer switches. I'm going to give you another option; install a true transfer switch and use it to feed an auxiliary circuit breaker panel. Move the critical loads (the circuits you want to run on generator power) to the new circuit breaker panel and then use the transfer switch to switch between the two.

USA, Universal Changeover Switch|Manual Generator|3PDT Center OFF|Rotary Cam| RV Transfer Swith| Pedestal Power Supply | Boat Panel | Power Source| Utility | Line | Shore| Back-up Power| Solar Energy| Battery Charger| Rectifier | Transfer Switch|
 
  #3  
Old 06-03-13, 01:21 PM
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The link seems to be having some issues. Can you please provide a working link.
 
  #4  
Old 06-03-13, 01:36 PM
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The link works for me. If it still doesn't for you copy and paste this link into your browser.

http://www.mqtekindustrialsupplies.com/60_AMP_MANUAL_TRANSFER_SWITCH_RV_BOAT_UNIVERSAL_p/mtsrv63.htm
 
  #5  
Old 06-03-13, 01:44 PM
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Some how on my laptop it not opening properly but opens well on my phone. Strange but I was able to look into it.

Not sure if this is what I need or looking for. Does this work in conjunction with transfer switch/ panel ?
 
  #6  
Old 06-03-13, 01:53 PM
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Does this work in conjunction with transfer switch/ panel?
This is a true transfer switch to be used as part of the setup that Furd described in post #2. That is, with a second panel: The subpanel you were considering adding anyway, in your earlier thread.
 
  #7  
Old 06-03-13, 01:58 PM
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Thanks for the response. So is the new layout going to be like this now

1.) Install a new sub panel
2.) In subpanel, should have the circuits which I want to run on generator
3.) Use the transfer switch to do the switching between gen and utility.

I might sound like bit confused as I am not sure how should I install this type of switch. Any link to manual or more inputs will greatly help.

Also is it that the options which I listed below are not good to consider or they will not resolve the issue which I am looking into ?
 
  #8  
Old 06-03-13, 02:32 PM
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Close. I would get the switch and the sub-panel and find the best place to mount them. The circuit breaker in the service (main) panel that is to power the sub-panel instead will power the switch and the switch powers the sub-panel. There will be additional conductors from the switch to the generator inlet connection.

Depending on your existing installation you may be able to use short pieces of straight conduit to interconnect the parts or you may find using flexible conduit to be easier. That particular switch has a 60 ampere capacity so you would use a 60 ampere circuit breaker and #6 copper conductors to the switch and on to the sub-panel. The sub-panel would be a MLO (main lugs only) type and can be of any ampere rating 60 amperes or higher as required to hold the necessary circuit breakers. In my home I used a 125 ampere panel just because it was the least expensive and had spaces for eight full-size or twin circuit breakers giving me a maximum of 16 circuits.

The wiring from the switch to the generator inlet connection only has to meet the maximum out put of the generator, in your case 27 amperes so this wiring can be #10 copper.

The advantages of using the switch instead of the transfer panels is that you get circuit breakers that are UL listed for branch circuit protection AND you get full neutral switching. The circuit breakers they use for transfer panels are generally only for supplemental protection and in a very strict interpretation are not approved for branch circuit protection. The neutral switching is important to avoid problems with GFCI protected circuits. Since most people consider the kitchen counter circuits as critical (coffee pot, toaster oven, microwave oven, etc.) the neutral switching is important. Also, with the switch you have only ONE switch to change to transfer from utility to generator power and back.
 
  #9  
Old 06-03-13, 02:51 PM
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Huh.. now getting some idea. Will prefer to put the details in a wiring diagram that will help.

Will you be able to share how the circuit breaker in the panel will be wired. Is it same a prewired transfer switches or differently.

Few Q's

- with this configuration, will I be able to use the new sub-panel as normal sub panel for creating new circuits if need be ?
- I will need this to be inspected, will there be any issues ?
- will this configuration power up the complete panel and sub panel or only sub panel (guess will answer if I know how subpanel will be wired)

I also confirmed, my generator has bonded neutral.
 
  #10  
Old 06-03-13, 03:02 PM
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I was just looking into the wiring diagram of the Gentran panle mentioned in my option 1 and looks like it kind of moving the breaker from main panel to subpanel. The black wire is connected to one of the breaker wire in transfer panel. And it appears to me that the breaker in old panel will be un-utilized, almost freeing up that space in main panel.

Is this correct ?
 
  #11  
Old 06-03-13, 03:53 PM
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In the main panel you have a 240 volt breaker no larger then the size of the transfer switch that supplies power to one imput of the transfer switch. The generator goes to the other input to the transfer switch. The output of the transfer switch goes to the subpanel.

 

Last edited by ray2047; 06-04-13 at 08:11 AM.
  #12  
Old 06-03-13, 04:04 PM
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it appears to me that the breaker in old panel will be un-utilized, almost freeing up that space in main panel.
That will be true with any transfer panel or any subpanel-plus-transfer-switch. The advantage of using a transfer switch, as Furd mentioned, is that you will also be transferring the neutral and be able to use any style of breaker.

I wonder whether AFCI breakers are available for your existing panel.
 
  #13  
Old 06-03-13, 11:32 PM
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Ray has done an excellent job with his diagram of how the transfer switch would be connected.

The new panel, fed via the transfer switch will contain circuit breakers for all the critical loads such as furnace, refrigerator, microwave oven, freezer (if you have one), kitchen counter top receptacles, the TV and video equipment, computer/Internet and a few strategic lights. All these circuits will be moved from the service panel to the new auxiliary (sub) panel so yes, you will have significant space opened in the service panel.

- with this configuration, will I be able to use the new sub-panel as normal sub panel for creating new circuits if need be ?
You could but it is best to limit all circuits in the new panel to ones that you will need when the utility power fails.

- I will need this to be inspected, will there be any issues ?
There shouldn't be. Many inspectors will be glad to see a switched neutral system instead of the more common unswitched neutral transfer panels.


- will this configuration power up the complete panel and sub panel or only sub panel (guess will answer if I know how subpanel will be wired)
When the utility power is present and the transfer switch is turned to the utility (or normal) position then both the service panel and the auxiliary panel will be powered from the utility. If you turn the transfer switch to the OFF position then only the service panel will be energized and if you turn the transfer switch to the generator position you can have the service panel energized by the utility power and the auxiliary panel energized by the generator, both at the same time.

When the utility power fails all you will need to do is turn the transfer switch to the generator position and get your generator running to power the auxiliary panel circuits. No circuits in the service panel can be energized from the generator under any circumstances.
 
  #14  
Old 06-03-13, 11:38 PM
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Nashkat1

it appears to me that the breaker in old panel will be un-utilized, almost freeing up that space in main panel.
That will be true with any transfer panel or any subpanel-plus-transfer-switch. The advantage of using a transfer switch, as Furd mentioned, is that you will also be transferring the neutral and be able to use any style of breaker.
Not quite. When using a common transfer panel the circuit breaker in the existing panel is used for the branch circuit under normal conditions. Only when the branch circuit is "transferred" to the generator (transfer) panel is the original circuit breaker not used but instead a circuit breaker on the transfer panel substituted. So no circuit breakers in the original panel are freed up for other use.
 
  #15  
Old 06-04-13, 08:22 AM
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Thanks all for providing all the valuable inputs so far. I now have a fair good understanding of what solution is being proposed. Based on this, if I look back at the wiring diagram of Gentran transfer switch, it looks almost similar to what Furd is suggesting. Please correct me if I am wrong here.

Instead of a switch there, in the panel they are using 2 pole circuit breaker. The only difference I do see is the neutral being still shared with main panel even when on generator mode. Not sure if this will make a difference.

This panel has standard circuit breakers and can be swapped as per the requirement.

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Note: Wiring of similar switch panel offered by reliance is different and in that case it still uses the circuit breaker in main panel which is not the case with Gentran switch (option1)
 
  #16  
Old 06-06-13, 07:58 AM
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Hi Furd/ Jay/ Nashkat,

please provide your inputs on this. Based on your advice I will be planning the setup on my end. So far the discussion had been very helpful
 
  #17  
Old 06-06-13, 09:24 AM
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The transfer switch in the diagram appears to be two pole. The one Furd recommends is three pole to avoid any problem with the generators neutral being connected to the house neutral.
 
  #18  
Old 06-06-13, 09:31 AM
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ok got it. Thats where the switch comes in play. When switched to generator the neutral from generator is not connected to main panel neural and remains with in generator circuit only. Great, thanks will start working in that direction.
 
  #19  
Old 06-06-13, 03:25 PM
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Here is more on that: http://www.doityourself.com/forum/el...-ground.html#b Note you may be able to but a neutral switching kit for the transfer switch you posted.

Also See:
http://www.doityourself.com/forum/el...g-issue.html#b

http://www.doityourself.com/forum/el...neutral.html#b
 
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