Suggestion for 24V/120V relay to control new outlet?
horizon
handle 120V, 7 amps. I'm looking to install it to control a new 120V
outlet that is going in an attic and needs to be controlled by a 24V
signal to turn it on. So, I'm looking for one that is cost effective
and can be mounted in some simple type of wiring box. If it can go in
the same box as the outlet, even better. I'd like to make this code
compliant and do it right. Plenty of space is available as I can
mount just about anything on a stud in the unfinished attic.
Thanks for any input.
horizon
After posting, I realized that while I said I only need 7 amps, since
it's an outlet on a 15 amp circuit I guess I actually need one capable
of min of 15 amps.
The Daring Dufas
I would use a RIB "relay in a box". Most electrical, HVAC and
electronics supply houses have them in stock.
http://hvac.functionaldevices.com/chartPilot.html
TDD
John Grabowski
Evan
What are you attempting to automatically control with the relay ?
What is the source of the input control signal ?
The most difficult issue for you is going to be finding an enclosure
which isolates the line voltage side of the relay from the low
voltage...
Depending on what you are using for your control input you might
want to find a relay that is made by the same company as the
rest of the equipment in place... It would also be a good idea
to obtain information from the OEM asking them if using the
equipment with an external relay is safe and won't interfere with
the normal operation just so that whatever accessory you are
going to be controlling via the relay won't void a warranty or
something like that if external relay terminals aren't provided...
~~ Evan
RBM
"horizon" <hori...@optonline.net> wrote in message
news:5e860e30-7028-44c8...@c7g2000vbc.googlegroups.com...
I was going to suggest a typical boiler relay like Taco SR501, but then I
saw both John Grabowski's, and gfretwell's replies, which make even more
sense. I don't know the one John suggested, but if you can live with the
amperage rating, it's a nice self contained unit. The rr7 that gfretwell
suggested, does need a 24 volt power supply, but it has a high amperage
rating, and those relays will last forever.
WW
"horizon" <hori...@optonline.net> wrote in message
news:5e860e30-7028-44c8...@c7g2000vbc.googlegroups.com...
DigiKey.com They will have what you need. ww
John Grabowski
*Roy I recently discovered these when a customer asked me to fix his closet
light. I thought that it was a nice compact unit that is made to fit in an
electrical box. It can also be used to replace relay switches. The OP
didn't mention what the load consisted of so I threw it out there for him to
decide if he could use it or not.
RBM
"John Grabowski" <jgra...@optonline.net> wrote in message
news:4be9d89e$0$22521$607e...@cv.net...
smaller. I've been buying from Tequipment recently, in fact I just got a
couple of proximity voltage testers today, and I got my last pair of Klein
lineman's from them. They have incredibly low prices, and being in NJ the
shipping is quick
John Grabowski
*The customer service at Tequipment was very good when I called for the
relay. I was going to drive down to pick it up, but the woman on the phone
said it would ship out the same day I called and I would have it the next
day. Sure enough I received it the next day. I will check out their prices
for tools.
JIMMIE
> On Tue, 11 May 2010 11:49:48 -0700 (PDT), horizon
>
> http://dale-electric.com/search.php?itemnumber=rr7&manufacturer=&keyw...
>
> The RR7 is a good choice
> It has a turn on and a turn off coil and latches in the last state you
> put it in. You control this with a momentary contact SPDT center off
> sw.
I controlled a relay like this powering the coil with only 9v
batteries. Since there is no hold-in current required you can put a
capacitor in parallel with 3 9volt batteries and use a couple of push
buttons to control it. The batteries will last practically their shelf
life.
Jimmie
HeyBub
Radio Shack, and similar, have remote switches for electrical outlets. Meant
to control things like lamps from across the room by radio control, they may
very well fit your needs. They're very cheap, like under ten dollars.
horizon
>
> - Show quoted text -
Of the suggestions, it looks like the one that will work is Daring
Dufas's relay in a box suggestion.
http://www.functionaldevices.com/pdf/RIBU1CW.pdf
It meets all my requirements:
easy to mount as it comes in it's own box
15 amps so controlling outlet on 15 amp circuit is OK
takes 24V input
available online for $21
One remaining question. Someone mentioned isolation of the 24V
circuit from 120V circuit? I would assume that since an electrical
equipment manufacturer is making these relays and they are UL listed
they are OK and meet code for my application even though the 24V wires
obviously go into the same box as the 120V wires?
Thanks again for the suggestions
jamesgangnc
>
> - Show quoted text -
Happens inside your heating systems so I'm guessing it's ok. If you
want to go cheap look behind some hvac contractors on the weekend for
junk ac compressors. They all have a relay that is pulled with 24vac
and handles anywhere form 20 amps and up. The hvac guys call them
contactors but it's just a relay.
Stormin Mormon
enough to get one.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
The Daring Dufas
> HVAC guys use 24 vac relays often enough. Should be easy
> enough to get one.
>
HVAC guys and control system guys like me use the RIB because
we're lazy and don't want to have to do a lot of screwing around
to accomplish a simple task. I'll pay $20 for a manufactured
solution rather than blow $100 worth of labor to build my own.
It's simple economics, I only build things that aren't available
off the shelf for a reasonable price.
TDD
Tony
> It is a sweet little relay. It's kind of like the electric heat relays only
> smaller. I've been buying from Tequipment recently, in fact I just got a
> couple of proximity voltage testers today, and I got my last pair of Klein
> lineman's from them. They have incredibly low prices, and being in NJ the
> shipping is quick
Are they "Tequipment.net"?. I could always use a source of low priced
Klein tools.
bud--
>
> One remaining question. Someone mentioned isolation of the 24V
> circuit from 120V circuit? I would assume that since an electrical
> equipment manufacturer is making these relays and they are UL listed
> they are OK and meet code for my application even though the 24V wires
> obviously go into the same box as the 120V wires?
>
They can both be in the same box when required - such as to connect to a
relay. Just keep the wires separate.
--
bud--
Nonny
That is one handy gizmo. How much are they? For anyone who
builds or plays around with home equipment, a few of those in the
spare parts bin would be terrific.
--
Nonny
On most days,
it's just not worth
the effort of chewing
through the restraints..
RBM
http://www.functionaldevices.com/pdf/RIBU1CW.pdf
If there is not separation between line and low voltage compartments within
the enclosure, I would recommend connecting line voltage conductors to the
low voltage terminals, then run them outside the enclosure through a
knockout, where you can splice them to typical low voltage conductors.
dpb
...
> I think I may see an out here. Upon closer inspection of the
> datasheet, the "relay in a box" that I want to use has what appears to
> be a plastic divider inside the box that seperates the low voltage
> section from the line voltage. Essentially it's like two seperate
> sections. Does this make it OK to use as I intended?
...
Yes.
--
N8N
> I'm looking for suggestions on a 24volt relay with contacts that can
> handle 120V, 7 amps. I'm looking to install it to control a new 120V
> outlet that is going in an attic and needs to be controlled by a 24V
> signal to turn it on. So, I'm looking for one that is cost effective
> and can be mounted in some simple type of wiring box. If it can go in
> the same box as the outlet, even better. I'd like to make this code
> compliant and do it right. Plenty of space is available as I can
> mount just about anything on a stud in the unfinished attic.
>
> Thanks for any input.
MR-101 or PAM-1 should do what you need, also I think Air Products
sells a similar one that mounts to a knockout of a handy box which
might be exactly what you're looking for. Don't remember part number
off the top of my head.
You probably won't be able to mount it in the same box as the outlet
for box fill reasons. I'd put it up in the attic so you don't have a
blank plate showing in your living space.
nate
jamesgangnc
> On Wed, 12 May 2010 12:34:57 -0400, "RBM" <r...@live.com> wrote:
>
> >"horizon" <horizo...@optonline.net> wrote in message
> the whole low voltage circuit needs to be treated as "class 1" which
> means it needs to be treated the same as you would treat the line
> voltage. Everything needs to be in a box, conduit or in a cable like
> Romex, end to end.
> When you have separation you can treat the low voltage side as "class
> 2" and you can take the liberties we usually have with "low voltage".
> It is really a little more complicated than that but you see what the
> general implications are.- Hide quoted text -
>
> - Show quoted text -
I wonder how it is that hvac components don't cause this issue.
Inside air handlers and outside units there is both 24vac and
110/220vac circuits. There is no specific separation of the wiring
inside the units. Low an dhigh get co-mingled all over the place
inside the units. And the 24vac wires go between units and the
thermostat without any special treatment. Does the brown jacket on
the low voltage wires count as satisfying the "class1" requirement?
Is all that is required a 2nd insulation layer like house wiring?
Because it would be easy enough to use thermostat wire for the low
side of whatever it is he is doing.
bud--
> the whole low voltage circuit needs to be treated as "class 1" which
> means it needs to be treated the same as you would treat the line
> voltage. Everything needs to be in a box, conduit or in a cable like
> Romex, end to end.
> When you have separation you can treat the low voltage side as "class
> 2" and you can take the liberties we usually have with "low voltage".
> It is really a little more complicated than that but you see what the
> general implications are.
"725.136-D Associated systems within enclosures
Class 2 and 3 circuit conductors in ...boxes... shall be permitted to be
installed with electric light, power... circuits where they are
introduced solely to connect the equipment connected to Class 2 and
Class 3 circuits, and where (1) OR (2) applies:
(1) The electric light, power... circuit conductors are routed to
maintain a minimum of 0.25 in. separation from the conductors and cables
of Class 2 and Class 3 circuits."
The separation required is 1/4" between conductors. The class 2
conductors can attach to the relay in Dufas's relay box as long as they
are kept 1/4" from power wires
Using a barrier is another method (725.136-B).
----------------
There should not be a problem with using a listed relay/contactor in a
listed box (where the combination is not listed together).
----------------
The relays that gfretwell and John showed take minimal space in normal
boxes, which makes them easy to use in normal wiring (in addition to
having the low voltage wires outside the box). It is an advantage if
they are installed where exposed (like a basement) to replace the relay
in the future. Both are available as 2 wire or latched (momentary) versions.
--
bud--
jamesgangnc
> gfretw...@aol.com wrote:
> > On Wed, 12 May 2010 12:34:57 -0400, "RBM" <r...@live.com> wrote:
>
> >> "horizon" <horizo...@optonline.net> wrote in message
>
> - Show quoted text -
Only a 1/4", that makes it pretty easy.
The Daring Dufas
> On May 12, 1:28 pm, gfretw...@aol.com wrote:
>> On Wed, 12 May 2010 12:34:57 -0400, "RBM" <r...@live.com> wrote:
>>
>> the whole low voltage circuit needs to be treated as "class 1" which
>> means it needs to be treated the same as you would treat the line
>> voltage. Everything needs to be in a box, conduit or in a cable like
>> Romex, end to end.
>> When you have separation you can treat the low voltage side as "class
>> 2" and you can take the liberties we usually have with "low voltage".
>> It is really a little more complicated than that but you see what the
>>
>> - Show quoted text -
>
> datasheet, the "relay in a box" that I want to use has what appears to
> be a plastic divider inside the box that seperates the low voltage
> section from the line voltage. Essentially it's like two seperate
> sections. Does this make it OK to use as I intended?
>
>
> http://www.functionaldevices.com/pdf/RIBU1CW.pdf
>
> I also looked at their app notes and they sure show a lot of
> applications where similar relays are being used in end user type
> installations as opposed to OEM.
I love their products, they save me a lot of time and money. I
keep a few general purpose models in stock. All of the trades,
electronic and industrial supply houses around here sell them.
TDD
bud--
And that applies to field wiring.
Factor wiring is covered by UL, which can have very different requirements.
--
bud--
Twayne
horizon <hori...@optonline.net> typed:
> I'm looking for suggestions on a 24volt relay with contacts
> that can handle 120V, 7 amps. I'm looking to install it to
> control a new 120V outlet that is going in an attic and
> needs to be controlled by a 24V signal to turn it on. So,
> I'm looking for one that is cost effective and can be
> mounted in some simple type of wiring box. If it can go in
> the same box as the outlet, even better. I'd like to
> make this code compliant and do it right. Plenty of space
> is available as I can mount just about anything on a stud
> in the unfinished attic.
>
> Thanks for any input.
Check out X10.com. They have what you need, it's wireless, and requires
nothing special but an outlet. You could have as many switches to control it
as you wanted. Right now it's $19.99 but prices change often there.
I've nothing to gain from them; just love their toys & products.
HTH,
Twayne`
horizon
> Innews:5e860e30-7028-44c8...@c7g2000vbc.googlegroups.com,
> horizon <horizo...@optonline.net> typed:
Thanks for the suggestion, but I can't use X10 for two reasons. One
is the control signal comes from a controller that already supplies a
24volt output. That also rules out some of the suggestions where the
transformer function is already included in the relay. The second
problem with X10 is reliability is a concern.
I still think Daring Dufas's relay in a box fits all the reqts.
bud--
> that enclosure. You can't take a wire out of there to another place
> and still call it class 2.
If the wires can't leave the box there is no particular usefulness in
being class 2 - they can be class 1.
The section quoted above says class 2 wires are "introduced solely to
connect the equipment". Reasonably read, "introduced" can mean to enter
the enclosure from the outside.
It is common practice for class 2 thermostat wires to enter a
"compartment" in a furnace/boiler where there are exposed insulated
power wires. IMHO the section I quoted allows that practice if the class
2 wires are kept separate from the power wires.
I dug out an old copy of UL913 which is for intrinsically safe
apparatus. As you are no doubt aware, intrinsically safe wiring is a lot
touchier than class 2. The standard has several methods to separate
field wiring terminals for intrinsically safe circuits from power
wiring. One of the methods is to separate the terminals by 2" (and
there are requirements for insulation rating and securing the wiring).
Intrinsically safe wiring can be in the same enclosure (like a control
panel) as the power wiring and terminate in the enclosure. The
intrinsically safe wiring is certainly intended to leave the enclosure.
> The handbook commentary on that section says
> "Power circuit and Class 2 circuit conductors can be permitted in the
> same motor-starter enclosure, where the Class 2 circuit source is the
> secondary of a control transformer in the same motor-starter
> enclosure. In such an installation, the Class 2 conductor insulation
> is not required to have the same voltage rating as the insulation on
> the power conductors in the same enclosure."
Doesn't say the wires can't leave the box.
> There is plenty of confusing language in 725. I think the whole thing
> should be evaluated and parts totally rewritten. You really have to be
> careful cherry picking out a few lines and believing that applies to
> your installation. Generally speaking you really need separation
> between class 2/3 and line power circuits. That is why they have class
> 1.
Separation? Like the 1/4" specified in the section I quoted?
Cherry picking?
725.136-A says class 2 (and 3) wires can't be in the same box,
compartment, raceway, ... with power and light wiring - *except* as
permitted by 725.136-B through I.
Several of these provisions (B, C, G) allow the combination if class 2
wiring is separated by a physical barrier. The clear intent to me is
that the barrier allows the class 2 to remain class 2. IMHO D-1, which I
quoted, similarly allows class 2 to remain class 2.
The section I quoted, 725.136-D, essentially has 3 parts (I quoted only
the first). Class 2 wires are allowed in an enclosure if it meets any
*one* of the parts
- separation of power and class 2 wires by at least 1/4"
- specified class 2 cable jacket and separation or barrier for wires
outside the jacket
- else the class 2 circuit becomes a class 1 circuit.
Becoming class 1 is a possibility, but only if one of the first 2
provisions is not met.
> Things that go on inside listed equipment do not necessarily apply to
> things you assemble yourself. Even there, the use of barriers is
> becoming the norm. The barrier itself may just be a little piece of
> mylar that the installer throws away but it was there when the product
> was listed. You also have to remember, cable jackets provide
> separation, so if the terminations are separated, the jacketed cable
> can go through the box.
For listed complete products the instructions from the manufacturer,
based on UL requirements, predominate.
If I put a UL listed contactor/relay in an appropriate box, and the
installation follows the listing for the contactor/relay, I don't see
why the NEC does not apply - specifically 725.136-D-1. What is the
violation?
> That also means you CAN pull a low voltage cable and line voltage
> cable in the same raceway,as long as you have separation where they
> terminate.
>
> Hold your nose legal ... Pull your CAT5 and Romex through the same
> conduit, extend the CAT 5 through the box and terminate it in a LV
> ring next to the box. Some might argue that you need a separation
> between the place where you split open the RX jacket and the exit of
> the CAT 5 but if you went in and out in the back of the box with the
> LV cable, stuffed in a mylar insulator and split the RX jacket on the
> outside of that you comply.
> A little dodgier is CAT 5 and THHN in the same pipe. Most AHJs will
> not let that fly.
You have posted that previously and it seemed quite reasonable.
When I looked at 725.136, it looks like class 2 and power can be in the
same raceway *if* the power (or class 2) is wired in UF (725.136-I).
What allows class 2 and Romex? Do the jackets constitute a "barrier"
(725.136-B)?
--
bud--
jamesgangnc
> On Thu, 13 May 2010 17:16:30 -0500, bud-- <remove.budn...@isp.com>
> wrote:
>
> >gfretw...@aol.com wrote:
> >> On Thu, 13 May 2010 09:43:48 -0500, bud-- <remove.budn...@isp.com>
> >> wrote:
>
> >> This is generally read to say that the entire class 2 system is inside
> >> that enclosure. You can't take a wire out of there to another place
> >> and still call it class 2.
>
> >If the wires can't leave the box there is no particular usefulness in
> >being class 2 - they can be class 1.
>
>
> >The section quoted above says class 2 wires are "introduced solely to
> >connect the equipment". Reasonably read, "introduced" can mean to enter
> >the enclosure from the outside.
>
> >It is common practice for class 2 thermostat wires to enter a
> >"compartment" in a furnace/boiler where there are exposed insulated
> >power wires. IMHO the section I quoted allows that practice if the class
> >2 wires are kept separate from the power wires.
>
> plastic barrier when it is shipped. It may not make it through the
> installation process and electrical inspectors don't really look
> inside that equipment.
>
> It is an interesting question I will bring up with the IAEI..
>
>
>
> >I dug out an old copy of UL913 which is for intrinsically safe
> >apparatus. As you are no doubt aware, intrinsically safe wiring is a lot
> >touchier than class 2. The standard has several methods to separate
> >field wiring terminals for intrinsically safe circuits from power
> >wiring. One of the methods is to separate the terminals by 2" (and
> >there are requirements for insulation rating and securing the wiring).
> >Intrinsically safe wiring can be in the same enclosure (like a control
> >panel) as the power wiring and terminate in the enclosure. The
> >intrinsically safe wiring is certainly intended to leave the enclosure.
>
> would fly with any inspector I know.
>
> >If I put a UL listed contactor/relay in an appropriate box, and the
> >installation follows the listing for the contactor/relay, I don't see
> >why the NEC does not apply - specifically 725.136-D-1. What is the
> >violation?
>
>
>
>
>
>
> >> That also means you CAN pull a low voltage cable and line voltage
> >> cable in the same raceway,as long as you have separation where they
> >> terminate.
>
> >> Hold your nose legal ... Pull your CAT5 and Romex through the same
> >> conduit, extend the CAT 5 through the box and terminate it in a LV
> >> ring next to the box. Some might argue that you need a separation
> >> between the place where you split open the RX jacket and the exit of
> >> the CAT 5 but if you went in and out in the back of the box with the
> >> LV cable, stuffed in a mylar insulator and split the RX jacket on the
> >> outside of that you comply.
> >> A little dodgier is CAT 5 and THHN in the same pipe. Most AHJs will
> >> not let that fly.
>
> >You have posted that previously and it seemed quite reasonable.
>
> >When I looked at 725.136, it looks like class 2 and power can be in the
> >same raceway *if* the power (or class 2) is wired in UF (725.136-I).
> >What allows class 2 and Romex? Do the jackets constitute a "barrier"
> >(725.136-B)?
>
> in the same pipe" thing. They are far more restrictive about how class
> 2 and line voltages need to be separated.- Hide quoted text -
>
> - Show quoted text -
I'll have to pay more attention next time I have one of my ac's or
heat pumps opened up. I've never noticed any plastic separators even
in a new unit. On straight AC the only 24vac is to pull the main
relay. That starts the whole thing up. On a hneat pump you have that
as well as 24vac switching the unit between airconditioning and heat.
bud--
> On Thu, 13 May 2010 17:16:30 -0500, bud-- <remove....@isp.com>
> wrote:
>
>> gfre...@aol.com wrote:
>>> On Thu, 13 May 2010 09:43:48 -0500, bud-- <remove....@isp.com>
>>> wrote:
>>>
>
>>> This is generally read to say that the entire class 2 system is inside
>>> that enclosure. You can't take a wire out of there to another place
>>> and still call it class 2.
>> If the wires can't leave the box there is no particular usefulness in
>> being class 2 - they can be class 1.
>>
>
>
>> connect the equipment". Reasonably read, "introduced" can mean to enter
>> the enclosure from the outside.
IMHO "introduced" clearly allows external class 2 wires to enter a box
to connect to "the equipment connected to Class 2 ... circuits".
As I said in my previous post, 725.136-D has 3 options for class 2
wiring entering a box that has power wiring. Separation by at least 1/4"
is one option. Only if the first 2 options are not used does 136-D
explicitly require the class 2 wiring be class 1.
>> It is common practice for class 2 thermostat wires to enter a
>> "compartment" in a furnace/boiler where there are exposed insulated
>> power wires. IMHO the section I quoted allows that practice if the class
>> 2 wires are kept separate from the power wires.
>
> Again this is a listed assembly and I bet a new one has some kind of
> plastic barrier when it is shipped. It may not make it through the
> installation process and electrical inspectors don't really look
> inside that equipment.
>
> It is an interesting question I will bring up with the IAEI..
I agree that it is listed apparatus and should generally be beyond your
purview (if wired according to manufacturer instructions). But it is
compliant with what I understand is permitted by 725.136-D (class 2 and
power wires in the same "compartment").
>> I dug out an old copy of UL913 which is for intrinsically safe
>> apparatus. As you are no doubt aware, intrinsically safe wiring is a lot
>> touchier than class 2. The standard has several methods to separate
>> field wiring terminals for intrinsically safe circuits from power
>> wiring. One of the methods is to separate the terminals by 2" (and
>> there are requirements for insulation rating and securing the wiring).
>> Intrinsically safe wiring can be in the same enclosure (like a control
>> panel) as the power wiring and terminate in the enclosure. The
>> intrinsically safe wiring is certainly intended to leave the enclosure.
>
> You can certainly try it and see what your AHJ says but I doubt it
> would fly with any inspector I know.
The AHJ would be arguing with what is explicitly allowed by UL.
And, IMHO, what is allowed by 725.136-D.
>>> That also means you CAN pull a low voltage cable and line voltage
>>> cable in the same raceway,as long as you have separation where they
>>> terminate.
>>>
>>> Hold your nose legal ... Pull your CAT5 and Romex through the same
>>> conduit, extend the CAT 5 through the box and terminate it in a LV
>>> ring next to the box. Some might argue that you need a separation
>>> between the place where you split open the RX jacket and the exit of
>>> the CAT 5 but if you went in and out in the back of the box with the
>>> LV cable, stuffed in a mylar insulator and split the RX jacket on the
>>> outside of that you comply.
>>> A little dodgier is CAT 5 and THHN in the same pipe. Most AHJs will
>>> not let that fly.
>> You have posted that previously and it seemed quite reasonable.
>>
>> When I looked at 725.136, it looks like class 2 and power can be in the
>> same raceway *if* the power (or class 2) is wired in UF (725.136-I).
>> What allows class 2 and Romex? Do the jackets constitute a "barrier"
>> (725.136-B)?
>
>
> BTW there are plenty of inspectors who say I am wrong about this "both
> in the same pipe" thing. They are far more restrictive about how class
> 2 and line voltages need to be separated.
But inspectors enforce the same code.......
I thought your options sounded reasonable.
IMHO 725.136-I clearly allows THHN power wires in the same raceway with
class 2 that is in UF. Now if they would just make #18 UF...
I always liked taping UF with class 2 to the power conduit for
installations like external condenser/compressors.
--
bud--
SMS
> I'm looking for suggestions on a 24volt relay with contacts that can
> handle 120V, 7 amps. I'm looking to install it to control a new 120V
> outlet that is going in an attic and needs to be controlled by a 24V
> signal to turn it on. So, I'm looking for one that is cost effective
> the same box as the outlet, even better. I'd like to make this code
> compliant and do it right. Plenty of space is available as I can
> mount just about anything on a stud in the unfinished attic.
>
> Thanks for any input.
24VAC or 24VDC?
For 24VAC what you want is a pump start relay that works with 24VAC
sprinkler systems. Already complete in a box. Start here:
"http://www.google.com/products?q=pump+relay+irrigation&hl=en&aq=f".
For a 24VDC coil, 10A contacts relay go to
"http://www.allelectronics.com/make-a-store/item/RLY-2024/24-VDC-DPDT-10-AMP-RELAY//1.html".
You'll have to put it into an enclosure yourself.
Tony
I pictured the plastic separator type in a building, not in the unit.
bud--
> On Fri, 14 May 2010 10:09:12 -0500, bud-- <remove....@isp.com>
> wrote:
>
>> I always liked taping UF with class 2 to the power conduit for
>> installations like external condenser/compressors.
>>
>> --
>> bud--
>
> Using a cable as support and using UF as a whip.
> You can tape the thermo cable to the (freon) line set but they still
> want a liquidtight raceway for the power.
OMG - a virtual red tag.
No sure I was clear on what I meant. When I was installing them long ago
I used sealtite conduit for power. (Or Minneapolis allowed, and probably
preferred back then, flex.)
I suggested tying class 2, in UF, to the sealtight - which is allowed
(300.11-B-2).
I would rather keep the wiring away from the refer guys, but reading
your post reminded me that I tied the UF to the insulated low pressure
line - the hole the refer guys put into the house was too convenient.
I wouldn't want to run power and class 2 in the same raceway even if
allowed.
======================
If I remember right, a couple people linked to your website for the
drill rig explosion/fire. Nice piece.
--
bud--
Twayne
bud-- <remove....@isp.com> typed:
A "Class 2" xfmr is simply a double-insulated transformer without an earth
ground on its plug, nor a polarized plug.
A "Class 1" xfmr requires a third wire, the earth ground pin on its plug.
The "Class of xfmr is a UL/CSA et al classification which approves the xfmr
and nothing else as safety approved. Secondary ckts attached to the output
of a xfmr are not subject to UL/CSA et al safety testing unless a voltage in
it equals or is more than 42VDC or 42V ac p-p. The original spec, UL1459
(now superceded but not changed in this area) is online for those who wish
to read it. I -think- the CSA spec was CS-03.
Whatever class 1 & 2 means ckt-wise, I don't know; it's not a UL/CSA et
al type spec but might be NEC, NFPA or otherwise.
HTH,
Twayne`
bud--
>
> A "Class 2" xfmr is simply a double-insulated transformer without an earth
> ground on its plug, nor a polarized plug.
> A "Class 1" xfmr requires a third wire, the earth ground pin on its plug.
> The "Class of xfmr is a UL/CSA et al classification which approves the xfmr
> and nothing else as safety approved.
The primary characteristic of class 1, 2, and 3 power sources is that
they are power limited. There is a specified maximum voltage, current
and power you can get from the source. For a class 2 24V transformer the
max current is 8A - the maximum current you get if you short circuit the
transformer.
Because the power is limited, the downstream circuit does not have to
meet the general wiring requirements of the NEC. Article 725 is used
instead.
Twayne
bud-- <remove....@isp.com> typed:
> Twayne wrote:
>>
>> A "Class 2" xfmr is simply a double-insulated transformer
>> without an earth ground on its plug, nor a polarized plug.
>> A "Class 1" xfmr requires a third wire, the earth ground
>> pin on its plug. The "Class of xfmr is a UL/CSA et al
>> classification which approves the xfmr and nothing else as
>> safety approved.
>
> The primary characteristic of class 1, 2, and 3 power
> sources is that they are power limited. There is a
> specified maximum voltage, current and power you can get
> from the source. For a class 2 24V transformer the max
> current is 8A - the maximum current you get if you short
> circuit the transformer.
I think you're confused between class definitions for Safety and what the
NEC defines; they are different.
Class 1, 2, and 3 CIRCUITS are classified as remote-control, signaling, and
power-limited circuits in the National Electrical Code (NEC).
Class 1 and 2 Power Supplies determines the insulation PROPERTIES of a power
supply and there is no Class 3. To the layman, they either need the third
ground wire or not (1 & 2 respectively).
The 8 Amp limitation IN NEC has nothing to do with UL/CSA et al
classifications. A transformer can output any current it can be designed for
as long as it meets the insulation and overvoltage/current test
specifications and meet the safety requirements.
Class 1, 2, 3 as used in the NEC as you can see above is quite different.
While saftey is of course a concern, simply limiting an output to 8 amps
would not deem it to be "safe". The NEC is concerned with wiring, and the
Safety is concerned with safety. Two different worlds. A google for UL
1459 might be enlightening for you. You apparently already have some
NEC information, or I'd assume so at least. You know NEC and I know Safety;
perhaps between the two of us, we could purchse/outfit/install equipment for
a home<G>.
HTH,
Twayne`
Twayne
>>
>> A "Class 2" xfmr is simply a double-insulated transformer
>> without an earth ground on its plug, nor a polarized plug.
>> A "Class 1" xfmr requires a third wire, the earth ground
>> pin on its plug. The "Class of xfmr is a UL/CSA et al
>> classification which approves the xfmr and nothing else as
>> safety approved.
>
> The primary characteristic of class 1, 2, and 3 power
> sources is that they are power limited. There is a
> specified maximum voltage, current and power you can get
> from the source. For a class 2 24V transformer the max
> current is 8A - the maximum current you get if you short
> circuit the transformer.
No. You're mixing up NEC/Safety agencies. UL and CSA and all like agencies
only have classes 1 and 2, no class 3, and they deal with the safety aspects
of a power transformer and its container, and must be so tested/listed in
order to be sold legally anywhere in the US or Canada. You are trying to
apply NEC wiring classses to the safety classes, incorrectly. The
definitions are exactly as I stated.
NEC Class 1, 2, and 3 circuits are classified as remote-control, signaling,
and power-limited circuits in the National Electrical Code (NEC).
Transformers are NOT required to meet ANY of those requirements. The 8A is a
wiring issue and part of the NEC, NOT part of safety. Look up UL 1459 and
you'll see what I mean. A transformer/power supply does not HAVE to be power
limited and in fact most are not, and if it's NOT power limited, that
section does not apply. Most transformers are NOT power limited but per
Safety agencies can never, under ANY load including locked rotors,
solenoids, short ckts, etc., can never present a fire or safety hazard to
anyone or anything.
A class 1 OR class 2 24V transformer sold in North America is required to
have UL or CSA or equivalent markings and submissions or be listed as a
component. INSTALLATION of same is where NEC comes in, and may or may not
apply; usually not. If it does not claim to be a class 3 installation
device, then it's a moot point; other parts of the NEC will apply.
HTH,
Twayne`
bud--
> In news:cb695$4bf1626f$cde8d543$25...@DIALUPUSA.NET,
> bud-- <remove....@isp.com> typed:
>> Twayne wrote:
>>> A "Class 2" xfmr is simply a double-insulated transformer
>>> without an earth ground on its plug, nor a polarized plug.
>>> A "Class 1" xfmr requires a third wire, the earth ground
>>> pin on its plug. The "Class of xfmr is a UL/CSA et al
>>> classification which approves the xfmr and nothing else as
>>> safety approved.
>> The primary characteristic of class 1, 2, and 3 power
>> sources is that they are power limited. There is a
>> specified maximum voltage, current and power you can get
>> from the source. For a class 2 24V transformer the max
>> current is 8A - the maximum current you get if you short
>> circuit the transformer.
>
> I think you're confused between class definitions for Safety and what the
> NEC defines; they are different.
I think you're confused about nearly everything.
> Class 1, 2, and 3 CIRCUITS are classified as remote-control, signaling, and
> power-limited circuits in the National Electrical Code (NEC).
Limiting the discussion to class 2, which many people are familiar with
(thermostat, doorbell):
Class 2 circuits are class 2 because they are _powered by a class 2
power supply_.
> Class 1 and 2 Power Supplies determines the insulation PROPERTIES of a power
> supply and there is no Class 3. To the layman, they either need the third
> ground wire or not (1 & 2 respectively).
So if I buy a UL listed class 2 transformer, according to you, it is not
power limited and can not be used to power a class 2 circuit. What a
bizarre idea. Make that a stupid idea.
No class 3? UL category XOKV - "TRANSFORMERS, CLASS 2 AND CLASS 3".
> The 8 Amp limitation IN NEC has nothing to do with UL/CSA et al
> classifications. A transformer can output any current it can be designed for
> as long as it meets the insulation and overvoltage/current test
> specifications and meet the safety requirements.
That will surprise UL.
> Class 1, 2, 3 as used in the NEC as you can see above is quite different.
> While saftey is of course a concern, simply limiting an output to 8 amps
> would not deem it to be "safe". The NEC is concerned with wiring, and the
> Safety is concerned with safety. Two different worlds. A google for UL
> 1459 might be enlightening for you.
It might be a lot more enlightening for you.
UL 1459 is "Telephone power supplies" (and has probably been withdrawn).
You are probably the only person that thinks we are talking about
telephones.
Class 2 transformers are listed under UL 1585, "Class 2 and Class 3
Transformers." (There is that pesky "class 3" again.) They are power
limited "in accordance with ANSI/NFPA 70, �National Electrical Code� (NEC)"
Some other standards may be applicable such as UL 1310, "Class 2 Power
Units" which also comply "with Class 2 voltage, current and volt-ampere
limits as specified in ANSI/NFPA 70, 'National Electrical Code'."
Note the reference to the power limits in the NEC.
Information is from the UL White Book.
Again you are posting nonsense.
Four months ago, in a thread about utility PF correction caps, you told
HeyBub "next time I'll be a lot more careful."
Obviously not.
Again.
<G>
--
bud--
Twayne
one of the 5085's. But I'm not tempted to refute anything you say because
you are still getting things terribly mixed up. Perhaps you should brush up
on how to read these specs too. Like, parts 1 & 2 apply unless excepted by 3
and so forth.
Sorry; I don't have the time to mess with your refusal to get the proper
information assembled for the project at hand.
HTH,
Twayne`
n news:1a08$4bf22de6$cde8d5bc$26...@DIALUPUSA.NET,
> ANSI/NFPA 70, National Electrical Code (NEC)"
bud--
> You're right, I cited the wrong spec; it's probably actually something like
> one of the 5085's. But I'm not tempted to refute anything you say because
> you are still getting things terribly mixed up.
Translation: you are wrong but won't admit it.
At least you admitted when you were wrong about utility PF correction caps.
> Perhaps you should brush up
> on how to read these specs too. Like, parts 1 & 2 apply unless excepted by 3
> and so forth.
I have no problem reading specs.
Like - from UL:
Class 2 transformers are listed under UL 1585, "Class 2 and Class 3
Transformers." They are power limited "in accordance with ANSI/NFPA 70,
�National Electrical Code� (NEC)"
Repeating again - from UL: The transformers are power limited "in
accordance with ANSI/NFPA 70, �National Electrical Code� (NEC)"
Perhaps you should brush up on the English language.
Explain what makes a class 2 door bell circuit class 2.
> Sorry; I don't have the time to mess with your refusal to get the proper
> information assembled for the project at hand.
Describe your "project at hand". I want to make sure I never get
anywhere near it.
bud--