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  #1   Report Post  
Way Back Jack
 
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Default Home Generator / Automatic Transfer Switch

It's 15kw and the available automatic transfer switch comes in 8, 10,
or 12 circuit versions.

Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?
  #2   Report Post  
toller
 
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Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?


Cause you simply don't have more than 8 circuits you need to power during a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.


  #3   Report Post  
Greg O
 
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"Way Back Jack" wrote in message
...
It's 15kw and the available automatic transfer switch comes in 8, 10,
or 12 circuit versions.

Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?


Price?
You only need 8?
Greg


  #4   Report Post  
Way Back Jack
 
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On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:


Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?


Cause you simply don't have more than 8 circuits you need to power during a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.


OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.

Thanx, Jack
  #5   Report Post  
toller
 
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"Way Back Jack" wrote in message
...
On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:


Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?


Cause you simply don't have more than 8 circuits you need to power during
a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.


OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.

If the water heater is 240v, then you have 7 circuits there. All these
items should be on their own circuit. Or is this a trick question?
Adding one circuit for some lights and your TV gets you to 8.
(I don't have a water heater, sumppump, well, or softener; so 4 was plenty
for me.)




  #6   Report Post  
Way Back Jack
 
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On Mon, 14 Mar 2005 00:02:46 GMT, "toller" wrote:


"Way Back Jack" wrote in message
...
On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:


Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?

Cause you simply don't have more than 8 circuits you need to power during
a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.


OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.

If the water heater is 240v, then you have 7 circuits there. All these
items should be on their own circuit. Or is this a trick question?
Adding one circuit for some lights and your TV gets you to 8.
(I don't have a water heater, sumppump, well, or softener; so 4 was plenty
for me.)


No trick question. I'm just stupid on these issues and trying to
learn. Thanks.

Jack
  #7   Report Post  
Doug Miller
 
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In article 1110762826.da03817dab4404b254e2c71e1ad4489f@bubba news, (Way Back Jack) wrote:
On Mon, 14 Mar 2005 00:02:46 GMT, "toller" wrote:
"Way Back Jack" wrote in message
...
On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:
Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?

Cause you simply don't have more than 8 circuits you need to power during
a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.

OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.


Water softener is obviously not a critical device.

If the water heater is 240v, then you have 7 circuits there.


No, six circuits. But two of them are 240V circuits (the water heater, and the
well pump). Five if you subtract the unnecessary water softener.

All these
items should be on their own circuit. Or is this a trick question?


That's just silly. There's no need to put each of these on its own circuit.
Neither a furnace blower nor a sump pump is a particularly high-current
device, so these two could share a circuit, and still have capacity left to
support lights or outlets. And a water softener draws hardly any current, so
it could share a 120V circuit with any of the other loads.

Adding one circuit for some lights and your TV gets you to 8.


Lights can share a circuit with either the refrigerator or the furnace and
sump pump, as long as you don't try to turn night into day.

So a more realistic count at this point is
two 240V circuits:
- water heater
- well pump
two 120V circuits
- oil furnace + sump pump + optional water softener + a few outlets
- refrigerator + some lights

(I don't have a water heater, sumppump, well, or softener; so 4 was plenty
for me.)


I *hope* you mean you don't have an *electric* water heater... ;-)

No trick question. I'm just stupid on these issues and trying to
learn. Thanks.


No, not "stupid". Uninformed.

Ignorance can be cured, but stupidity is forever.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?
  #8   Report Post  
m Ransley
 
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240v takes 2 transfer panel circuits, Sumps, refrigerator, water
sofener etc etc, get a clamp on amp meter and measre start up peak-surge
and run load, dont guess or read the labels, measure it. Refrigerators
can pull as little as 350 surge and 100 running or 1300 surge and 600
running., Surge load is critical with a gen, surge can be 8 times run
load, but is usualy 4-6 times. Figure it wrong and you will ruin your
gen. Even if it is a auto panel you dont want all loads comming on at
the same time. You also will have 2 amp meters, you need to balance your
load for max gen life. I like manual panels, I can monitor usage and
balance the load. Also what brand is your generator and what is run load
and peak load . Is furnace modern with a circuit board. A rough guess
you could have a 50-60 Amp surge with what you mentioned Your gen may
not handle it and die on startup or burn up trying. figure your startup
load and run load first. Any high draw motor give it is own circuit.
Your 2 - 240 v will take 4 circuits.

  #9   Report Post  
m Ransley
 
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Each generator leg puts out 120, so balancing is important.

  #10   Report Post  
stretch
 
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The refrigerator should always have it's own circuit per code. Same
with the furnace and water heater.


Stretch



  #11   Report Post  
toller
 
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"Way Back Jack" wrote in message
news:1110762826.da03817dab4404b254e2c71e1ad4489f@b ubbanews...
On Mon, 14 Mar 2005 00:02:46 GMT, "toller" wrote:


"Way Back Jack" wrote in message
...
On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:


Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?

Cause you simply don't have more than 8 circuits you need to power
during
a
blackout; and all the extra wiring fills up your breaker box pretty
fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th
and
6th circuits, as I only really wanted 4.

OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.

If the water heater is 240v, then you have 7 circuits there. All these
items should be on their own circuit. Or is this a trick question?
Adding one circuit for some lights and your TV gets you to 8.
(I don't have a water heater, sumppump, well, or softener; so 4 was plenty
for me.)


No trick question. I'm just stupid on these issues and trying to
learn. Thanks.

Sure. We all have to learn.
As someone pointed out, some well pumps are 240v and will require 2
circuits. You can check that easily by seeing it it uses a single or double
breaker.
(However, he was foolish to suggest putting the furnace and sumppump on the
same circuit; hopefully the electrician who wired your house knew better.
They, like the refrigerator, are critical appliances and need their own
circuits.)


  #12   Report Post  
L. M. Rappaport
 
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On Sun, 13 Mar 2005 22:53:23 GMT, (Way Back Jack)
wrote (with possible editing):

On Sun, 13 Mar 2005 22:24:14 GMT, "toller" wrote:


Why would you choose a switch with 8 or 10 circuit capability if your
generator supports 12?


Cause you simply don't have more than 8 circuits you need to power during a
blackout; and all the extra wiring fills up your breaker box pretty fast.
I have a 6 circuit transfer switch and had trouble deciding on the 5th and
6th circuits, as I only really wanted 4.


OK, in your estimation, how many circuits would be typically involved
in this bare-bones scenario:

Refrigerator; oil-fired furnace; well/water storage tank; water
neutralizer/softener; water heater; sump-pump.

Thanx, Jack


Refrigerator is 120v and requires a separate circuit (NEC).
Oil furnace is 120v and requires a separate circuit (NEC).
Well is either 120v or 240v and requires a separate circuit (NEC).
Water heater is 240v and requires a separate circuit (NEC).
Sump pump is 120v and I think requires a separate circuit.

That's a total of 6 or 7 circuits and you've left nothing for
lighting. If it were me, I'd have at least 2 or 3 extra circuits, so
I'd be buying at least a 10 circuit switch.

FWIW, what I did here with our 18kw diesel was to add a 200 amp
transfer switch and put it ahead of the entire distribution panel.
The generator is protected by a dual 60 amp breaker. With no electric
heat, is capable of running the entire house and often does. Your
only really big additional draws are an electric oven/range and (less
so) an electric dryer.

--

Larry
Email to rapp at lmr dot com

  #14   Report Post  
m Ransley
 
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Modern refrigerators do consume 1/4-1/3rd the power of 15 yr old units,
what is important is surge load not just saying it has to have its own
circuit. A modren VS DC furnace may only need 200 watts, or boiler 200
watts, and 19.5 cu.ft Sears frige 100 watts running. Sure alot of old
apliances needed their own circuit as power draw was higher, new
equipment often does not.

  #15   Report Post  
Chris Lewis
 
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According to Doug Miller :
In article , wrote:


Refrigerator is 120v and requires a separate circuit (NEC).
Oil furnace is 120v and requires a separate circuit (NEC).
Well is either 120v or 240v and requires a separate circuit (NEC).
Water heater is 240v and requires a separate circuit (NEC).
Sump pump is 120v and I think requires a separate circuit.


AFAIK the NEC does not require separate circuits in *any* of those cases. Do
you have a Code citation for that?


No code citation per-se (I'll look tonight if I remember), but the NEC
does require seperate circuits for all of the above (with the possible
exception of the fridge and sump pump. Older code certainly permitted
fridges to be on shared circuits).

CEC has required separate circuits (with some trivial exceptions - ie: you
can put an AC clock on the same circuit as a fridge) for all of the above
except possibly sump pumps.

Both codes tend to require separate circuits for every electrical
motor that may come on at the same time. At least for motors in the 1/4HP
and up range (ie: furnace blowers), unless they're specifically approved
together (ie: a furnace air blower and oil pump).

In any event... the subject was how many circuits do you need to be able to
adequately power your home from a generator, in an emergency - not how many
circuits are required by Code during normal operation.


Since the "automatic transfer" equipment would be shared w.r.t. "emergency"
versus "normal", "normal" use would be in violation of code _too_.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.


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zxcvbob
 
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Chris Lewis wrote:
According to Doug Miller :

In article , wrote:




Refrigerator is 120v and requires a separate circuit (NEC).
Oil furnace is 120v and requires a separate circuit (NEC).
Well is either 120v or 240v and requires a separate circuit (NEC).
Water heater is 240v and requires a separate circuit (NEC).
Sump pump is 120v and I think requires a separate circuit.




AFAIK the NEC does not require separate circuits in *any* of those cases. Do
you have a Code citation for that?



No code citation per-se (I'll look tonight if I remember), but the NEC
does require seperate circuits for all of the above (with the possible
exception of the fridge and sump pump. Older code certainly permitted
fridges to be on shared circuits).

CEC has required separate circuits (with some trivial exceptions - ie: you
can put an AC clock on the same circuit as a fridge) for all of the above
except possibly sump pumps.

Both codes tend to require separate circuits for every electrical
motor that may come on at the same time. At least for motors in the 1/4HP
and up range (ie: furnace blowers), unless they're specifically approved
together (ie: a furnace air blower and oil pump).


In any event... the subject was how many circuits do you need to be able to
adequately power your home from a generator, in an emergency - not how many
circuits are required by Code during normal operation.



Since the "automatic transfer" equipment would be shared w.r.t. "emergency"
versus "normal", "normal" use would be in violation of code _too_.



You do realize the refrigerator will be just fine for a short time
without power, and during an extended outage you can run it from an
extension cord? The same thing goes for the sump pump. The water
softener doesn't need backup electric power (after an extended power
outage you might have to do a manual recharge.) So not everything you
might want to use during a power outage needs to be wired to the
transfer panel. It depends how hands-on you are willing to get.

If you don't want to have to do anything, put a big automatic transfer
switch between the meter and the main panel and use the main panel for
all the power distribution.

Best regards,
Bob
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Chris Lewis
 
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According to zxcvbob :
Chris Lewis wrote:
Since the "automatic transfer" equipment would be shared w.r.t. "emergency"
versus "normal", "normal" use would be in violation of code _too_.


You do realize the refrigerator will be just fine for a short time
without power, and during an extended outage you can run it from an
extension cord? The same thing goes for the sump pump. The water
softener doesn't need backup electric power (after an extended power
outage you might have to do a manual recharge.) So not everything you
might want to use during a power outage needs to be wired to the
transfer panel. It depends how hands-on you are willing to get.

If you don't want to have to do anything, put a big automatic transfer
switch between the meter and the main panel and use the main panel for
all the power distribution.


For the most part, if the person has a smallish/portable generator
(say, 5500W or less), I tend to suggest that they don't bother with
transfer switches and the like, and rely on (adequate!) extension cords.
The only "prep" work they might wish to consider is to rewire the
critical hard-wired devices (ie: furnace blowers) so that they're running
off receptacles (replacement of hard wire with flexible power cord, plug
and receptacle). Secondly, prepare a "hard point" for where the generator
will be parked in use (stanchions/chains/padlocks[+], "rain roof" etc), and
possibly a resealable hole for where the cords go through into the house.

[Never _ever_ run your generator in an enclosed space.]

Then, when you have a power failure, you just follow a schedule of
what needs to be connected and for how long. For example, a fridge
will probably be perfectly fine with half an hour of operation for
every 6-12 hours of outage. A freezer even less. Keeping in mind
the max output of the generator...

Strictly speaking, running things like furnaces off "cords" is
frequently a code violation, but most inspectors will consider
"emergency preparedness" to be a good reason. Just make sure
that the installation is otherwise in excess of code. Eg: _adequate_
power cords - SOW cable for "appliance cord", not lamp cord,
with appropriate measures to prevent damage to it.

As for "adequate extension cords", anything but smallish loads should
be fed with heavy duty extension cords. Eg: consider 12ga "contractor
grade"/"building site" cords[*] as your _minimum_.

[+] There's a special place in hell reserved for those who steal
emergency equipment during an emergency. _Especially_ from emergency
measures organizations. During the "great" ice storm, we actually
had people stealing generators from hospitals and road maintenance
depots.
[*] The brightly coloured fat and expensive ones. Often rated "SOW"
or better.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.
  #20   Report Post  
HorneTD
 
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Chris Lewis wrote:
Strictly speaking, running things like furnaces off "cords" is
frequently a code violation, but most inspectors will consider
"emergency preparedness" to be a good reason. Just make sure
that the installation is otherwise in excess of code. Eg: _adequate_
power cords - SOW cable for "appliance cord", not lamp cord,
with appropriate measures to prevent damage to it.

Double pole, double throw, center off switches; that are suitable for
use as transfer switches for individual loads; are readily available and
when wired to a flanged inlet they make a fully code compliant way to
run a furnace from a portable generator.
--
Tom H
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