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  #1  
Old 12-27-2009, 07:45 PM
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Default [EVDL] ceramic heater wiring

I have taken the under dash heater box out of my 120 volt Jet 007 and am ready to install a ceramic element from a portable ceramic heater. I have already installed a relay. There are five wires attached to the top of the ceramic element as I have seen on websites where others have done this. How do I wire the heater for maximum heat? The two red wires from the top are hooked together. The two blue wires from the top are hooked together. The center wire is a black wire. If I plug it in so that the red wires are attached to one lead and the blue wires are hooked to the other I get heat. I am not sure I am getting all 1500 watts though. What about the black center wire? Should it be connected with the blue wires for maximum heat?

Clif
(In cold Ohio.)
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  #2  
Old 12-27-2009, 08:05 PM
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Default Re: [EVDL] ceramic heater wiring

The heater core that I have is a Sunbeam and the ceramic element, fan, and
fan shroud looks identical to the one at
http://zuglet.com/ev/saturn/heater.html. I thought the pictures might make
my question more clear.

Thanks,
Clif


--------------------------------------------------
From: "Clif Martin" <xxx@xxx.xxx.com>
Sent: Sunday, December 27, 2009 8:23 PM
To: <xxx@xxx.xxx.edu>
Subject: [EVDL] ceramic heater wiring

> I have taken the under dash heater box out of my 120 volt Jet 007 and am
> ready to install a ceramic element from a portable ceramic heater. I have
> already installed a relay. There are five wires attached to the top of
> the ceramic element as I have seen on websites where others have done
> this. How do I wire the heater for maximum heat? The two red wires from
> the top are hooked together. The two blue wires from the top are hooked
> together. The center wire is a black wire. If I plug it in so that the
> red wires are attached to one lead and the blue wires are hooked to the
> other I get heat. I am not sure I am getting all 1500 watts though. What
> about the black center wire? Should it be connected with the blue wires
> for maximum heat?
>
> Clif
> (In cold Ohio.)
> -------------- next part --------------
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  #3  
Old 12-27-2009, 08:35 PM
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Default Re: [EVDL] ceramic heater wiring

Hello Clif,

The first thing you always do before you remove any electrical device, is to
trace all the wires, label them and make a wiring diagram of the wiring.

The Red, Blue, Black does not reference to anything. A electrical feeder
circuit that comes directly from 3 phase wye 120/208 volt are color code
Black, Red and Blue. Being that's it a 120 volt device and the Red are pair
together as well as the Blue, this might be two 120 volt elements connected
in parallel.

The Black may be a center tap between two sets of elements which may be the
high heat setting. All it may be doing is switching two elements in series
and apply 120 voltage across them which will be a low heat.

Switching all the elements in parallel and applying 120 voltage will be the
higher heat setting.

There should be a wiring diagram on the heater container to make sure if
this is how it is wire.

Make sure you use the high temperature limit switch, which cuts the power if
the temperature gets too high. There should also be a operating limit that
you can adjust. This allows the heater to come up to a certain temperature
before the fans comes on, or you will be blowing cold air in.

This operating limit and/or fan limit can also turn on and off your existing
heater fan. The high voltage wiring should be remove from the limits
controls and use 12 volt control voltage in these circuits.

Roland




----- Original Message -----
From: "Clif Martin" <xxx@xxx.xxx.com>
To: <xxx@xxx.xxx.edu>
Sent: Sunday, December 27, 2009 5:23 PM
Subject: [EVDL] ceramic heater wiring


> I have taken the under dash heater box out of my 120 volt Jet 007 and am
> ready to install a ceramic element from a portable ceramic heater. I have
> already installed a relay. There are five wires attached to the top of
> the ceramic element as I have seen on websites where others have done
> this. How do I wire the heater for maximum heat? The two red wires from
> the top are hooked together. The two blue wires from the top are hooked
> together. The center wire is a black wire. If I plug it in so that the
> red wires are attached to one lead and the blue wires are hooked to the
> other I get heat. I am not sure I am getting all 1500 watts though. What
> about the black center wire? Should it be connected with the blue wires
> for maximum heat?
>
> Clif
> (In cold Ohio.)
> -------------- next part --------------
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  #4  
Old 12-27-2009, 09:26 PM
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Default Re: [EVDL] ceramic heater wiring

Hi Bob,

[quote] Bob Bath <xxx@xxx.xxx> wrote:
> Hey, since we're on the subject, just a fair warning: one ceramic element=
will not be enough for OH. If it's not enough for OR (32F/0C lately), i=
t's not enough for OH. If there is any way to use an anderson connector =
and provide you with an option of selecting your ceramic element in the hea=
ter box, _or_ a hair-dryer adjustable unit, try to have both available, pre=
ferably in parallel. You'll be glad you did!Just my 0.02 from having "be=
en there".peace,
>

How do you have the hair-dryer plumbed in? Is it hooked to one set of
vents and the ceramic heater to another?

-- =

David D. Nelson
http://evalbum.com/1328

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  #5  
Old 12-27-2009, 10:17 PM
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Default Re: [EVDL] ceramic heater wiring

Clif,

>From the picture on the Saturn conversion website
it is pretty clear how the 4 ceramic elements in the
heater are connected as they are all in series with
the connection wires:
blue-red-black-red-blue.
It is easy to make half and full heat by connecting
only the black and red wires so the middle two
elements are on, and to wire the blue to the black
to get full heat.
Just follow the wires and write + and - at each wire
connection and you will see that all elements are
connected alternating - and + pack voltage when you
attach the blue and black to - and red to +.

Make sure that the over-temp switch operates a relay,
as it will not able to break pack DC voltage!

Success,

Cor van de Water
Director HW & Systems Architecture Group
Proxim Wireless Corporation http://www.proxim.com
Email: xxx@xxx.xxx Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: xxx@xxx.xxx
Tel: +1 408 383 7626 VoIP: +31 20 3987567 FWD# 25925
Tel: +91 (040)23117400 x203 XoIP: +31877841130

-----Original Message-----
From: xxx@xxx.xxx.edu [mailto:xxx@xxx.xxx.edu] On
Behalf Of Clif Martin
Sent: Monday, December 28, 2009 7:31 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] ceramic heater wiring

The heater core that I have is a Sunbeam and the ceramic element, fan,
and fan shroud looks identical to the one at
http://zuglet.com/ev/saturn/heater.html. I thought the pictures might
make my question more clear.

Thanks,
Clif


--------------------------------------------------
From: "Clif Martin" <xxx@xxx.xxx.com>
Sent: Sunday, December 27, 2009 8:23 PM
To: <xxx@xxx.xxx.edu>
Subject: [EVDL] ceramic heater wiring

> I have taken the under dash heater box out of my 120 volt Jet 007 and
> am ready to install a ceramic element from a portable ceramic heater.
I have
> already installed a relay. There are five wires attached to the top
of
> the ceramic element as I have seen on websites where others have done
> this. How do I wire the heater for maximum heat? The two red wires
> from the top are hooked together. The two blue wires from the top are

> hooked together. The center wire is a black wire. If I plug it in so

> that the red wires are attached to one lead and the blue wires are
> hooked to the other I get heat. I am not sure I am getting all 1500
> watts though. What about the black center wire? Should it be
> connected with the blue wires for maximum heat?
>
> Clif
> (In cold Ohio.)
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  #6  
Old 12-27-2009, 10:27 PM
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Default Re: [EVDL] ceramic heater wiring

Here is my drawing for all to see. Please heed the warnings of others as my drawing does not show the over temp safety switch and
that it should interrupt the relay/contactor coil that you use to switch the heater on.

http://home.gci.net/~saintbernard/Heater_Core_Wiring.pdf

Mike

> -----Original Message-----
> From: xxx@xxx.xxx.edu [mailto:xxx@xxx.xxx.edu] On Behalf Of Clif Martin
> Sent: Sunday, December 27, 2009 4:24 PM
> To: xxx@xxx.xxx.edu
> Subject: [EVDL] ceramic heater wiring
>
> I have taken the under dash heater box out of my 120 volt Jet 007 and am ready to install a ceramic element from
> a portable ceramic heater. I have already installed a relay. There are five wires attached to the top of the ceramic
> element as I have seen on websites where others have done this. How do I wire the heater for maximum heat?
> The two red wires from the top are hooked together. The two blue wires from the top are hooked together. The
> center wire is a black wire. If I plug it in so that the red wires are attached to one lead and the blue wires are
> hooked to the other I get heat. I am not sure I am getting all 1500 watts though. What about the black center wire?
> Should it be connected with the blue wires for maximum heat?
>
> Clif
> (In cold Ohio.)
> -------------- next part --------------
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  #7  
Old 12-28-2009, 09:35 AM
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Default Re: [EVDL] ceramic heater wiring

Not to differ with Roland, but I worry about the statement

"Switching all the elements in parallel and applying 120 voltage will be
the higher heat setting."

Only because that is really sets of elements already in series.
so you have the blades and the grill. the blades are the PTC elements
and the grill between them is both heat sink to give you the heat and
electrical connection from one PTC to the next. It makes the standard
core of 4 elements in series . Note the wires are connected to the fins!

http://www.mightyboyev.com/Conversion%20Process%20-%20Electrical%20-%20Heater.htm

The 5 wires are connected between each and one on each end.
IIRC they are have a wide voltage rating each but put out the most heat
at 70V each. They will operate on 120 just fine as they heat faster then
increase in resistance and therefore are fine on 120. but 240 in the
"all parallel" config may get beyond the upper knee and go into melt down.
I can't find the charts I had but we can deduce from the way they are
wired in consumer products.

http://www.dbk-usa.com/products/ptcheaters/ptcheaters.htm

So you can arrange them a few ways (polarity not critical) 4S = 4 in
series 2P = 2 in parallel

connect 1(+) and 5(-) for 4S
connect 1,5(+) and 3(-) for 2S2P
connect 2,4(+) and 1,3,5(-) for 4P

I think these are low med and high on 120VAC
If you have a 240V pack I would say only use the low and med first and
see if that is enough heat. The way PTC's work, you will get the same
wattage of output at each setting. I am just worried about the last one
on higher voltage packs (and consumer grade PTC units)

> Hello Clif,
>
> The first thing you always do before you remove any electrical device, is to
> trace all the wires, label them and make a wiring diagram of the wiring.
>
> The Red, Blue, Black does not reference to anything. A electrical feeder
> circuit that comes directly from 3 phase wye 120/208 volt are color code
> Black, Red and Blue. Being that's it a 120 volt device and the Red are pair
> together as well as the Blue, this might be two 120 volt elements connected
> in parallel.
>
> The Black may be a center tap between two sets of elements which may be the
> high heat setting. All it may be doing is switching two elements in series
> and apply 120 voltage across them which will be a low heat.
>
> Switching all the elements in parallel and applying 120 voltage will be the
> higher heat setting.
>
> There should be a wiring diagram on the heater container to make sure if
> this is how it is wire.
>
> Make sure you use the high temperature limit switch, which cuts the power if
> the temperature gets too high. There should also be a operating limit that
> you can adjust. This allows the heater to come up to a certain temperature
> before the fans comes on, or you will be blowing cold air in.
>
> This operating limit and/or fan limit can also turn on and off your existing
> heater fan. The high voltage wiring should be remove from the limits
> controls and use 12 volt control voltage in these circuits.
>
> Roland
>

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  #8  
Old 12-29-2009, 08:25 AM
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Default Re: [EVDL] ceramic heater wiring

Do you have an Ohm meter? If so measure the resistance between terminals.
Mine has 5 terminals. It is simply a long resistor with 5 terminals, one at
each end (1&5), one in the middle (3), and two midway between 1&3 and 5&3.
You can use different terminals to get the best (out of the options)
resistance for your pack voltage. The lower the resistance the more current
and more heat you get. For example if the resistance between 1&5 is 40 Ohm,
then the resistance between 1&3 and 5&3 will each be 1/2 that or 20 Ohm.
With 120V pack voltage you would get V*V/R = 350W with B+ and B- connected
between 1&5, whereas if you connect B+ = 120V to 1&5 and B- to 3 you would
have two 20 Ohm in parallel or 10 Ohm, and V*V/R = 1440W in this case.

The resistance of ceramic heaters is a U-shaped curve, with higher
resistance at lower temperatures and higher temperatures and minimum around
100 - 130F. If left on with no blower it will heat up and current will
reduce to less than 1/2A giving little heat. You will get the most heat at
a blower setting that keeps the heater in the 100-130F range.

Tom


[quote]Clif Martin wrote:
>
> I have taken the under dash heater box out of my 120 volt Jet 007 and am
> ready to install a ceramic element from a portable ceramic heater. I have
> already installed a relay. There are five wires attached to the top of
> the ceramic element as I have seen on websites where others have done
> this. How do I wire the heater for maximum heat? The two red wires from
> the top are hooked together. The two blue wires from the top are hooked
> together. The center wire is a black wire. If I plug it in so that the
> red wires are attached to one lead and the blue wires are hooked to the
> other I get heat. I am not sure I am getting all 1500 watts though. What
> about the black center wire? Should it be connected with the blue wires
> for maximum heat?
>
> Clif
> (In cold Ohio.)
> -------------- next part --------------
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--
View this message in context: http://n4.nabble.com/ceramic-heater-wiring-tp989547p990302.html
Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com.

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  #9  
Old 12-31-2009, 10:25 AM
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Default Re: [EVDL] ceramic heater wiring

Thanks to everyone for all the help with the ceramic heater. I have tested
it out of the car and it works fine. I have the relay and wiring ready to
reinstall the heater. I have one more question. It is a 1500 watt heater.
Since P=IV, I =P/V that would be 1500 Watts/120 volts = 12.5 amps. What
rated fuse should I use? (Volts and Amps) Where can I find the fuse and
holder? It is 120 Volt DC (more like 130 Volts when fully charged) instead
of AC so how would this affect the rating?

Happy New Year Everyone!
Clif

>
[quote]> Clif Martin wrote:
>>
>> I have taken the under dash heater box out of my 120 volt Jet 007 and am
>> ready to install a ceramic element from a portable ceramic heater. I
>> have
>> already installed a relay. There are five wires attached to the top of
>> the ceramic element as I have seen on websites where others have done
>> this. How do I wire the heater for maximum heat? The two red wires
>> from
>> the top are hooked together. The two blue wires from the top are hooked
>> together. The center wire is a black wire. If I plug it in so that the
>> red wires are attached to one lead and the blue wires are hooked to the
>> other I get heat. I am not sure I am getting all 1500 watts though.
>> What
>> about the black center wire? Should it be connected with the blue wires
>> for maximum heat?
>>
>> Clif
>> (In cold Ohio.)
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://lists.sjsu.edu/mailman/private/ev/attachments/20091227/82abd2f4/attachment.html
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>>
>>
>>
>
> --
> View this message in context:
> http://n4.nabble.com/ceramic-heater-wiring-tp989547p990302.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
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  #10  
Old 12-31-2009, 11:25 AM
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Default Re: [EVDL] ceramic heater wiring

[quote]Clif Martin wrote:
> Thanks to everyone for all the help with the ceramic heater. I have tested
> it out of the car and it works fine. I have the relay and wiring ready to
> reinstall the heater. I have one more question. It is a 1500 watt heater.
> Since P=IV, I =P/V that would be 1500 Watts/120 volts = 12.5 amps. What
> rated fuse should I use? (Volts and Amps) Where can I find the fuse and
> holder? It is 120 Volt DC (more like 130 Volts when fully charged) instead
> of AC so how would this affect the rating?

The advertised wattage of a ceramic heater is a marketing lie. None of
them ever draw the rated wattage. A typical number for a "1500 watt"
heater is more like 900 watts.

The resistance of the ceramic element changes with temperature. The
hotter it gets, the *lower* the wattage and the less current it draws.
So, it might typically start at a higher wattage; but it rapidly falls
off as it warms up.

The resistance is also strongly affected by the airflow through it. When
you're running it in an EV on something other than 120v, the current
will also be different. Thus, the only way you can properly size a fuse
is to measure the actual current it draws in your application. Then use
a fuse of about 150% to 200% of this current.

I was on vacation, and so missed some of your earlier posts. Just in case:

- Be sure to use a fuse that is *DC rated* for your pack voltage.
If only an AC voltage rating is given, the DC rating is about 1/4th
of that. If you have trouble finding one, contact me off-list --
I have a good collection of them.

- Be sure the relay that switches the fuse is also DC rated. Otherwise,
its contacts are likely to weld *on*! Again, if the relay only has
AC ratings, assume the DC rating is 1/4th of that (120vac = 30vdc).
You can use multiple contacts in series to increase the rating.
A 4-pole relay with 120vac contacts can switch 30+30+30+30=120vdc
with all the contacts in series.

- Put a "snubber" across the relay's contacts. For a 10 amp heater,
a 0.22uf to 1uf capacitor with a 22ohm to 47ohm resistor in series
will do it. It greatly reduces contact arcing.

- If the fan quits, the ceramic heater SUPERHEATS! The ceramic itself
can stand the heat; it won't fail. But it can melt the wiring and
dashboard plastic ducting, and could even set it on fire! Provide
some way to shut off the heater if the fan fails or the airflow is
blocked.

- PS: The switches, fuses, overtemperature cutouts, and thermostats
that came in the heater WILL NOT WORK ON HIGH VOLTAGE DC! Don't use
them for high voltage DC!
--
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
leeahart earthlink.net | That's how the light gets in -- Leonard Cohen

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