DIY Electric Car Forums banner

1 - 19 of 19 Posts

·
Registered
Joined
·
70 Posts
Discussion Starter #1
Funny this discussion of standards, when most people still call US standard
voltage 110v when it's been 120v for over a half of a century.

Either that, or it's showing our average age! =)

I was in Australia for about a month recently and I get really used to their
240v 50hz power. It's really nice to be able to pull 2.4kw from a
"standard" wall outlet. I noticed some small appliances and tools took
advantage of this and offered an improvement in performance over their US
counterparts.

Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all you
110'ers) although most newer circuits deliver more, even if that's all the
outlet is technically rated for.

-Phil

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #2
[This might be off topic... or it might help people understand
electricity better]

(-Phil-) wrote:
> Funny this discussion of standards, when most people still call US standard
> voltage 110v when it's been 120v for over a half of a century.
...
> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all you
> 110'ers) although most newer circuits deliver more, even if that's all the
> outlet is technically rated for.

I was getting 157v out of a 20-amp, 125v circuit the other day. If
there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
circuit and consider that 'nominal'), is 157v in it or out of it for
this circuit?

I'm wondering if voltage surges and fluctuations could be responsible
for the remarkably high failure rate of light bulbs in my house (even
well-rated Sylvania CFLs, which I've been slowly converting to).

To try and yank this back to EVs: does voltage variability in the home
impact how the charger handles charging?

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #3
I sure hope someone talks about the OT light bulb thing. I am about to go
crazy going through bulbs in my old farm house. Perhaps if someone has some
help they could contact me off list.

Aliza

----- Original Message -----
From: <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, October 29, 2007 12:59 PM
Subject: Re: [EVDL] Electrical Standards


>
> [This might be off topic... or it might help people understand
> electricity better]
>
> (-Phil-) wrote:
>> Funny this discussion of standards, when most people still call US
>> standard
>> voltage 110v when it's been 120v for over a half of a century.
> ...
>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>> you
>> 110'ers) although most newer circuits deliver more, even if that's all
>> the
>> outlet is technically rated for.
>
> I was getting 157v out of a 20-amp, 125v circuit the other day. If
> there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
> circuit and consider that 'nominal'), is 157v in it or out of it for
> this circuit?
>
> I'm wondering if voltage surges and fluctuations could be responsible
> for the remarkably high failure rate of light bulbs in my house (even
> well-rated Sylvania CFLs, which I've been slowly converting to).
>
> To try and yank this back to EVs: does voltage variability in the home
> impact how the charger handles charging?
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #4
157v is WAY out of spec!

That is a dangerous condition! I suspect a floating neutral. I'd call the
power company ASAP!

Anything within 5% of 120 is considered in spec. If it's over 127v or under
113v it's out of spec, and you can call the power company.

If the power company is at fault delivering out of tolerance voltage, they
are liable for repairs to your appliances!

In your case though, my guess is a floating neutral, which could be a
problem on your side, not the power companies. Anything up to the meter is
their responsibility, anything after it is yours.

-Phil
----- Original Message -----
From: <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, October 29, 2007 12:59 PM
Subject: Re: [EVDL] Electrical Standards


>
> [This might be off topic... or it might help people understand
> electricity better]
>
> (-Phil-) wrote:
>> Funny this discussion of standards, when most people still call US
>> standard
>> voltage 110v when it's been 120v for over a half of a century.
> ...
>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>> you
>> 110'ers) although most newer circuits deliver more, even if that's all
>> the
>> outlet is technically rated for.
>
> I was getting 157v out of a 20-amp, 125v circuit the other day. If
> there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
> circuit and consider that 'nominal'), is 157v in it or out of it for
> this circuit?
>
> I'm wondering if voltage surges and fluctuations could be responsible
> for the remarkably high failure rate of light bulbs in my house (even
> well-rated Sylvania CFLs, which I've been slowly converting to).
>
> To try and yank this back to EVs: does voltage variability in the home
> impact how the charger handles charging?
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #5
157v is WAY out of spec!

That is a dangerous condition! I suspect a floating neutral. I'd call the
power company ASAP!

Anything within 5% of 120 is considered in spec. If it's over 127v or under
113v it's out of spec, and you can call the power company.

If the power company is at fault delivering out of tolerance voltage, they
are liable for repairs to your appliances!

In your case though, my guess is a floating neutral, which could be a
problem on your side, not the power companies. Anything up to the meter is
their responsibility, anything after it is yours.

-Phil
----- Original Message -----
From: <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, October 29, 2007 12:59 PM
Subject: Re: [EVDL] Electrical Standards


>
> [This might be off topic... or it might help people understand
> electricity better]
>
> (-Phil-) wrote:
>> Funny this discussion of standards, when most people still call US
>> standard
>> voltage 110v when it's been 120v for over a half of a century.
> ...
>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>> you
>> 110'ers) although most newer circuits deliver more, even if that's all
>> the
>> outlet is technically rated for.
>
> I was getting 157v out of a 20-amp, 125v circuit the other day. If
> there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
> circuit and consider that 'nominal'), is 157v in it or out of it for
> this circuit?
>
> I'm wondering if voltage surges and fluctuations could be responsible
> for the remarkably high failure rate of light bulbs in my house (even
> well-rated Sylvania CFLs, which I've been slowly converting to).
>
> To try and yank this back to EVs: does voltage variability in the home
> impact how the charger handles charging?
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #6
If you want to check if it is at your side or the
power company's then you can check either different
outlets that attach to adjacent breakers (which should
have alternating connections to each of the two phases
of 120V that make up the 240V service).

If you measure 140V from one outlet and 100V from another
then you will need to open up your service panel and
measure the voltage of both phases coming into your
service panel, if you still see 140V and 100V there,
coming from the meter and relative to neutral then it
is likely that the neutral is disconnected somewhere
upstream and the *load* balance between the two legs of
phase - neutral and neutral - other phase is what
determines the voltage.
If you switch on a heavy duty 120V appliance like a
microwave or garage opener, you may see the voltage shift
between the two phases.
In that case: immediately call the power company to send
someone out or else you can experience broken appliances
and lights from over- or undervoltage.

Normally there is at least 10% tolerance in the specs of
line voltages, though long lines and heavy load can
occasionally cause the voltage to go beyond that range.
That is the reason most devices will work on only 90V AC
but not many expect a voltage over 132V, unless they can
work on 230V without reconfiguation, then they usually
go all the way to 265V (240V + 10%)

Cor van de Water
Systems Architect
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [email protected]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Second Life: www.secondlife.com/?u=3b42cb3f4ae249319edb487991c30acb

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of (-Phil-)
Sent: Monday, October 29, 2007 1:38 PM
To: [email protected]
Subject: Re: [EVDL] Electrical Standards

157v is WAY out of spec!

That is a dangerous condition! I suspect a floating neutral. I'd call the
power company ASAP!

Anything within 5% of 120 is considered in spec. If it's over 127v or under 113v it's out of spec, and you can call the power company.

If the power company is at fault delivering out of tolerance voltage, they are liable for repairs to your appliances!

In your case though, my guess is a floating neutral, which could be a problem on your side, not the power companies. Anything up to the meter is their responsibility, anything after it is yours.

-Phil
----- Original Message -----
From: <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, October 29, 2007 12:59 PM
Subject: Re: [EVDL] Electrical Standards


>
> [This might be off topic... or it might help people understand
> electricity better]
>
> (-Phil-) wrote:
>> Funny this discussion of standards, when most people still call US
>> standard
>> voltage 110v when it's been 120v for over a half of a century.
> ...
>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>> you
>> 110'ers) although most newer circuits deliver more, even if that's all
>> the
>> outlet is technically rated for.
>
> I was getting 157v out of a 20-amp, 125v circuit the other day. If
> there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
> circuit and consider that 'nominal'), is 157v in it or out of it for
> this circuit?
>
> I'm wondering if voltage surges and fluctuations could be responsible
> for the remarkably high failure rate of light bulbs in my house (even
> well-rated Sylvania CFLs, which I've been slowly converting to).
>
> To try and yank this back to EVs: does voltage variability in the home
> impact how the charger handles charging?
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #7
Keep in mind that there are usually not "2 phases" anywhere in residential
service. It is single-phase 120/240v.

You can say "2 hots" or "2 legs" but you can't say "2 phases" because they
do not have any strange timing relationship, only 180 degrees.

The power company takes a single leg (phase) from their system and runs it
into a transformer. The transformer has a 240v winding, and they connect
the neutral to the center-tap.

If you actually had "2 phases", you would end up with 208v across the 2
hots, not 240.

-Phil
----- Original Message -----
From: "Cor van de Water" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>;
<[email protected]>
Sent: Monday, October 29, 2007 1:51 PM
Subject: Re: [EVDL] Electrical Standards


> If you want to check if it is at your side or the
> power company's then you can check either different
> outlets that attach to adjacent breakers (which should
> have alternating connections to each of the two phases
> of 120V that make up the 240V service).
>
> If you measure 140V from one outlet and 100V from another
> then you will need to open up your service panel and
> measure the voltage of both phases coming into your
> service panel, if you still see 140V and 100V there,
> coming from the meter and relative to neutral then it
> is likely that the neutral is disconnected somewhere
> upstream and the *load* balance between the two legs of
> phase - neutral and neutral - other phase is what
> determines the voltage.
> If you switch on a heavy duty 120V appliance like a
> microwave or garage opener, you may see the voltage shift
> between the two phases.
> In that case: immediately call the power company to send
> someone out or else you can experience broken appliances
> and lights from over- or undervoltage.
>
> Normally there is at least 10% tolerance in the specs of
> line voltages, though long lines and heavy load can
> occasionally cause the voltage to go beyond that range.
> That is the reason most devices will work on only 90V AC
> but not many expect a voltage over 132V, unless they can
> work on 230V without reconfiguation, then they usually
> go all the way to 265V (240V + 10%)
>
> Cor van de Water
> Systems Architect
> Proxim Wireless Corporation http://www.proxim.com
> Email: [email protected] Private: http://www.cvandewater.com
> Skype: cor_van_de_water IM: [email protected]
> Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
> Fax: +1 408 731 3675 eFAX: +31-87-784-1130
> Second Life: www.secondlife.com/?u=3b42cb3f4ae249319edb487991c30acb
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of (-Phil-)
> Sent: Monday, October 29, 2007 1:38 PM
> To: [email protected]
> Subject: Re: [EVDL] Electrical Standards
>
> 157v is WAY out of spec!
>
> That is a dangerous condition! I suspect a floating neutral. I'd call
> the
> power company ASAP!
>
> Anything within 5% of 120 is considered in spec. If it's over 127v or
> under 113v it's out of spec, and you can call the power company.
>
> If the power company is at fault delivering out of tolerance voltage, they
> are liable for repairs to your appliances!
>
> In your case though, my guess is a floating neutral, which could be a
> problem on your side, not the power companies. Anything up to the meter
> is their responsibility, anything after it is yours.
>
> -Phil
> ----- Original Message -----
> From: <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Monday, October 29, 2007 12:59 PM
> Subject: Re: [EVDL] Electrical Standards
>
>
>>
>> [This might be off topic... or it might help people understand
>> electricity better]
>>
>> (-Phil-) wrote:
>>> Funny this discussion of standards, when most people still call US
>>> standard
>>> voltage 110v when it's been 120v for over a half of a century.
>> ...
>>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>>> you
>>> 110'ers) although most newer circuits deliver more, even if that's all
>>> the
>>> outlet is technically rated for.
>>
>> I was getting 157v out of a 20-amp, 125v circuit the other day. If
>> there is a nominal range (and I have seen 110-120 out of a 15-amp, 120v
>> circuit and consider that 'nominal'), is 157v in it or out of it for
>> this circuit?
>>
>> I'm wondering if voltage surges and fluctuations could be responsible
>> for the remarkably high failure rate of light bulbs in my house (even
>> well-rated Sylvania CFLs, which I've been slowly converting to).
>>
>> To try and yank this back to EVs: does voltage variability in the home
>> impact how the charger handles charging?
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #9
From: Zeke Yewdall
> How is 180 degrees between the phases any less strange than 120
> degrees? It's just that generating two phase power from single phase
> power is very easy due to the phasors being aligned back to back.

A 180 degrees difference between phases is "split phase", not 2-phase power. 2-phase power has a 90 degree difference between phases. 2-phase motors are common because it is fairly easy to generate the second phase from 1-phase power with a series inductor or capacitor to the second phase winding.

--
"Excellence does not require perfection." -- Henry James
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart-at-earthlink.net

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #11
That's probably because it's the "Service Voltage" that's at 120V (plus or
minus 5 percent).
By the time it get's through the house wiring to the outlet, it's
typically down to 104V to 110V (I believe the spec is 120V +6 to -13
percent)

SO even though it's technically 120V, 110V is closer to what you normally
really get.

> Funny this discussion of standards, when most people still call US
> standard
> voltage 110v when it's been 120v for over a half of a century.
>
> Either that, or it's showing our average age! =)
>
> I was in Australia for about a month recently and I get really used to
> their
> 240v 50hz power. It's really nice to be able to pull 2.4kw from a
> "standard" wall outlet. I noticed some small appliances and tools took
> advantage of this and offered an improvement in performance over their US
> counterparts.
>
> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all you
> 110'ers) although most newer circuits deliver more, even if that's all the
> outlet is technically rated for.
>
> -Phil
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #12
If you have 104 volts at your outlet, you have a problem! The spec is 120
+/- 5%, at the outlet.

If your wiring is sized properly, you will see a few volts drop on high
current loads, but you should never see 104v!

-Phil
----- Original Message -----
From: "Peter VanDerWal" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Tuesday, October 30, 2007 12:15 AM
Subject: Re: [EVDL] Electrical Standards


> That's probably because it's the "Service Voltage" that's at 120V (plus or
> minus 5 percent).
> By the time it get's through the house wiring to the outlet, it's
> typically down to 104V to 110V (I believe the spec is 120V +6 to -13
> percent)
>
> SO even though it's technically 120V, 110V is closer to what you normally
> really get.
>
>> Funny this discussion of standards, when most people still call US
>> standard
>> voltage 110v when it's been 120v for over a half of a century.
>>
>> Either that, or it's showing our average age! =)
>>
>> I was in Australia for about a month recently and I get really used to
>> their
>> 240v 50hz power. It's really nice to be able to pull 2.4kw from a
>> "standard" wall outlet. I noticed some small appliances and tools took
>> advantage of this and offered an improvement in performance over their US
>> counterparts.
>>
>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>> you
>> 110'ers) although most newer circuits deliver more, even if that's all
>> the
>> outlet is technically rated for.
>>
>> -Phil
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
>
> --
> If you send email to me, or the EVDL, that has > 4 lines of legalistic
> junk at the end; then you are specifically authorizing me to do whatever I
> wish with the message. By posting the message you agree that your long
> legalistic signature is void.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #14
In the 20's and early 30's, the service entrance transformers were set at
110/220 volts which most of the load was lighting. So this configuration was
a common usage by lay persons even till now.

In the early 30's, more appliances and power loads were added which drop the
voltage by about 5 percent to about 105/210 volts. So at that time we
install transformers that have five 2.5% taps which the center tap (No. 3 or
sometimes call the C tap) was set at 115 volts at no load.

Motor ratings was then set at 115/230 volts which is still being use today
on single phase. On three phase these ratings are 120/208 volts. The
service factor on these motors are normally set from 1.15 to 1.25 percent,
(SF factor rating on the label of the motor), which is the over ampere
and/or voltage rating of the motor.

If the load was lightly load, then we would keep it on tap C. The allowable
voltage drop is 1 percent for lighting and 3 percent for power, which is
still held today.

Today tap C is now at 120 volts at no load and it is allow to drop to 116.6
volts for power circuits. Reading what my voltage is right now which I have
less than 1 kw of lighting on, my voltage is running at 121.2 volts. Power
circuits which could run about 15 kw drops to about 118.6 volts.

I had the power company tap my transformer to tap D to maintain this voltage
range at this load.

Roland


----- Original Message -----
From: "Peter VanDerWal" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Tuesday, October 30, 2007 1:15 AM
Subject: Re: [EVDL] Electrical Standards


> That's probably because it's the "Service Voltage" that's at 120V (plus or
> minus 5 percent).
> By the time it get's through the house wiring to the outlet, it's
> typically down to 104V to 110V (I believe the spec is 120V +6 to -13
> percent)
>
> SO even though it's technically 120V, 110V is closer to what you normally
> really get.
>
> > Funny this discussion of standards, when most people still call US
> > standard
> > voltage 110v when it's been 120v for over a half of a century.
> >
> > Either that, or it's showing our average age! =)
> >
> > I was in Australia for about a month recently and I get really used to
> > their
> > 240v 50hz power. It's really nice to be able to pull 2.4kw from a
> > "standard" wall outlet. I noticed some small appliances and tools took
> > advantage of this and offered an improvement in performance over their
> > US
> > counterparts.
> >
> > Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
> > you
> > 110'ers) although most newer circuits deliver more, even if that's all
> > the
> > outlet is technically rated for.
> >
> > -Phil
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
>
>
> --
> If you send email to me, or the EVDL, that has > 4 lines of legalistic
> junk at the end; then you are specifically authorizing me to do whatever I
> wish with the message. By posting the message you agree that your long
> legalistic signature is void.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #15
No, it's 120V +/- 5% at the Service Entrance, i.e. at the meter.

The power company is NOT responsible for your house wiring, especially not
for looses in the house wiring.

> If you have 104 volts at your outlet, you have a problem! The spec is
> 120
> +/- 5%, at the outlet.
>
> If your wiring is sized properly, you will see a few volts drop on high
> current loads, but you should never see 104v!
>
> -Phil
> ----- Original Message -----
> From: "Peter VanDerWal" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Tuesday, October 30, 2007 12:15 AM
> Subject: Re: [EVDL] Electrical Standards
>
>
>> That's probably because it's the "Service Voltage" that's at 120V (plus
>> or
>> minus 5 percent).
>> By the time it get's through the house wiring to the outlet, it's
>> typically down to 104V to 110V (I believe the spec is 120V +6 to -13
>> percent)
>>
>> SO even though it's technically 120V, 110V is closer to what you
>> normally
>> really get.
>>
>>> Funny this discussion of standards, when most people still call US
>>> standard
>>> voltage 110v when it's been 120v for over a half of a century.
>>>
>>> Either that, or it's showing our average age! =)
>>>
>>> I was in Australia for about a month recently and I get really used to
>>> their
>>> 240v 50hz power. It's really nice to be able to pull 2.4kw from a
>>> "standard" wall outlet. I noticed some small appliances and tools took
>>> advantage of this and offered an improvement in performance over their
>>> US
>>> counterparts.
>>>
>>> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all
>>> you
>>> 110'ers) although most newer circuits deliver more, even if that's all
>>> the
>>> outlet is technically rated for.
>>>
>>> -Phil
>>>
>>> _______________________________________________
>>> For subscription options, see
>>> http://lists.sjsu.edu/mailman/listinfo/ev
>>>
>>
>>
>> --
>> If you send email to me, or the EVDL, that has > 4 lines of legalistic
>> junk at the end; then you are specifically authorizing me to do whatever
>> I
>> wish with the message. By posting the message you agree that your long
>> legalistic signature is void.
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #16
Zeke Yewdall wrote:
> I stand corrected. It seemed bizarre that you would run power with
> the phases not being distributed symmetrically to zero out the nuetral
> current, but a little internet research shows that it was quite common
> to generate and run four wire two phase with the two phases 90 degrees
> apart before three phase machines were developed.

2-phase and 3-phase (and in fact, all other numbers of phases except
single-phase) have the advantage that the instantaneous sum of the power
is a constant. This means the power produced by a generator or used by a
motor is constant -- no torque pulsations.

2-phase happens to need 4 wires. They are symmetrical around ground; you
can have a 5th neutral wire if desired. A 2-phase motor is more
complicated than a single-phase, but less complicated than 3-phase. This
is the attraction as far as the motor designer is concerned.

3-phase only need 3 wires -- that's the advantage as far as the power
company is concerned (fewer wire to route). The total wire size for a
given amount of power is still the same; it's just split into 3 parts
instead of 4 parts (so you don't save any copper). The higher the phase
count, the more complicated the motor is to wind.

Now, all of the above assumes sine waves. If you have square wave power
(like from an inverter), then the more phases you have, the smoother the
power. 4, 6, 12, and even 24 phase systems have been built.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #17
the standard is + or - 5% from the voltage measured at the load side of your service (125v) to the furthest device on the branch circuit .
----- Original Message -----
From: Peter VanDerWal<mailto:[email protected]>
To: Electric Vehicle Discussion List<mailto:[email protected]>
Sent: Tuesday, October 30, 2007 2:15 AM
Subject: Re: [EVDL] Electrical Standards


That's probably because it's the "Service Voltage" that's at 120V (plus or
minus 5 percent).
By the time it get's through the house wiring to the outlet, it's
typically down to 104V to 110V (I believe the spec is 120V +6 to -13
percent)

SO even though it's technically 120V, 110V is closer to what you normally
really get.

> Funny this discussion of standards, when most people still call US
> standard
> voltage 110v when it's been 120v for over a half of a century.
>
> Either that, or it's showing our average age! =)
>
> I was in Australia for about a month recently and I get really used to
> their
> 240v 50hz power. It's really nice to be able to pull 2.4kw from a
> "standard" wall outlet. I noticed some small appliances and tools took
> advantage of this and offered an improvement in performance over their US
> counterparts.
>
> Here in the US, we can generally only expect 1.8kw, (or 1.65kw for all you
> 110'ers) although most newer circuits deliver more, even if that's all the
> outlet is technically rated for.
>
> -Phil
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
>


--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #18
What kind of meter are people useing to measure their line voltage?

My fluke 877 true rms measures 117 solid all the time, but my other,
cheaper meters vary from 110 to 125 on the same plug. Something about AC
is a lot harder to get an accurate reading than DC.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #19
(-Phil-) wrote:
> 157v is WAY out of spec!
>
> That is a dangerous condition! I suspect a floating neutral. I'd call the
> power company ASAP!
>
> Anything within 5% of 120 is considered in spec. If it's over 127v or under
> 113v it's out of spec, and you can call the power company.

Sorry for the false alarm, folks, this was a case of PEBMAP (Problem
Exists Between Multimeter And Power).

157 mV is quite different from 157 V. I also followed the suggestion
for checking the relative voltages of a 240 outlet (table saw) and that
showed nominal voltage.

I still think I have fluctuations, and need to finish up with my plan to
use a multimeter and a PC to log voltage over time, but that's a
separate matter - and naught to do with EVs.

Thanks, all, and especially Phil.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
1 - 19 of 19 Posts
Top