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F40 CW bulbs with T12 ballasts?

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Andy

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Oct 29, 2010, 3:33:06 PM10/29/10
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I have a box of F40 CW bulbs that I would like to use up.

Can F40 CW lamps be used with ballasts for T12 bulbs?

Thanks,
Andy

RBM

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Oct 29, 2010, 4:57:10 PM10/29/10
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"Andy" <chocolate...@yahoo.com> wrote in message
news:25e67c0d-ed8b-4972...@p1g2000yqm.googlegroups.com...

If the lamps are F40T12CW,and the ballasts are for F40T12, they can


Andy

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Oct 30, 2010, 4:21:53 PM10/30/10
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On Oct 29, 3:57 pm, "RBM" <r...@live.com> wrote:
> "Andy" <chocolatemint77...@yahoo.com> wrote in message

I guess you misunderstood.

I have F40CW bulbs. (Older style than newer T12 bulbs)

Andy

RBM

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Oct 30, 2010, 4:45:00 PM10/30/10
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"Andy" <chocolate...@yahoo.com> wrote in message
news:c81b4952-db66-4780...@u17g2000yqi.googlegroups.com...

I guess you misunderstood.

Andy

Andy, I'm not sure what you mean old style, new style. A new T12 4' bi-pin
lamp is going to be 34 watts, but otherwise it's the same. I'm not sure
about magnetic ballasts but they make electronic ballasts that work for
either 34 or 40 watt T12 lamps. They don't work with the newer T8 4' bi-pin
lamps. For those, you need a T8 ballast


Andy

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Oct 30, 2010, 10:19:05 PM10/30/10
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On Oct 30, 3:45 pm, "RBM" <r...@live.com> wrote:
> "Andy" <chocolatemint77...@yahoo.com> wrote in message
>
> news:c81b4952-db66-4780...@u17g2000yqi.googlegroups.com...
> On Oct 29, 3:57 pm, "RBM" <r...@live.com> wrote:
>
> > "Andy" <chocolatemint77...@yahoo.com> wrote in message
>
> >news:25e67c0d-ed8b-4972...@p1g2000yqm.googlegroups.com...
>
> > >I have a box of F40 CW bulbs that I would like to use up.
>
> > > Can F40 CW lamps be used with ballasts for T12 bulbs?
>
> > > Thanks,
> > > Andy
>
> > If the lamps are F40T12CW,and the ballasts are for F40T12, they can
>
> I guess you misunderstood.
>
> I have F40CW bulbs. (Older style than newer T12 bulbs)
>
> Andy
>
> Andy, I'm not sure what you mean old style, new style. A new T12 4' bi-pin
> lamp is going to be 34 watts, but otherwise it's the same. I'm not sure
> about magnetic ballasts but they make electronic ballasts that work for
> either 34 or 40 watt T12 lamps. They don't work with the newer T8 4' bi-pin
> lamps. For those, you need a T8 ballast

The T12 bulbs were designed to be more efficient than the older F40CW
bulbs.

The T12 fixtures also have two pins, but the OLDER style bulbs will
not fit in them.

The T12 ballast that I have, does not list the F40CW bulb as among
those that will work with it.
It also doesn't warn against using it either.

If the ballast will safely light the F40CW bulb, I will use it.

I don't want the ballast overheating or something.

Andy

Andy

RBM

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Oct 31, 2010, 8:08:52 AM10/31/10
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"Andy" <chocolate...@yahoo.com> wrote in message
news:9a090ecc-fcfd-49f1...@26g2000yqv.googlegroups.com...

Andy

Andy

Bi-Pin T12 fluorescent tubes as well as T8 tubes, old or new, all use the
same sockets, and if they're the same length, will fit in the same fixtures.
Magnetic or electronic fluorescent ballasts are specific to the lamps that
they will work with. Those lamps, and their quantity will be listed on the
label of the ballast along with a wiring diagram. If the lamps you want to
use are not listed on the ballast, don't use it.


Andy

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Oct 31, 2010, 8:44:41 AM10/31/10
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They don't use the same socket, unless the fixture I recently bought
was incorrectly packed. :-)

I may post this on an electronics newsgroup.

Take care,
Andy

RBM

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Oct 31, 2010, 10:24:58 AM10/31/10
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"Andy" <chocolate...@yahoo.com> wrote in message
news:338625a3-b9ee-45f0...@j25g2000yqa.googlegroups.com...

Take care,
Andy

A T12 lamp only gives the diameter of the bulb. 12 eighths of an inch. There
are other types of T12 fluorescent lamps than the bi-pin type. There are
single pin industrials, and plastic oval pins used in HO and VHO, but all
T12 and T8 bi-pins use the same socket. It would help to have the exact
numbers and letters written on the lamp and the make and model of the
ballast


RBM

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Oct 31, 2010, 10:28:56 AM10/31/10
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"Andy" <chocolate...@yahoo.com> wrote in message
news:25e67c0d-ed8b-4972...@p1g2000yqm.googlegroups.com...

You don't need to go to another NG, just ping Don Klipstein. There's nothing
this guy doesn't know about bulbs


Don Klipstein

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Nov 1, 2010, 1:08:37 AM11/1/10
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In <25e67c0d-ed8b-4972...@p1g2000yqm.googlegroups.com>,

Provided the ballasts are rated for F40 or "40 watt", then the answer is
yes.

Better still if the ballasts are rated for both 40 watt and 34 watt,
or both F40 and F30T12.

Beware if the ballast (or wiring configuration thereof) is rated for
both 40-watt 32 watt and not 34 or 35 watt, especially 20's watts along
with 32. "True 40 watt" is "amp-hungry" from ballast output, and the
34 and 35 watt "energy saver versions" of F40T12 (especially the
"crankier" 34-watt one) are "amp-hungrier" still. 30-watt T12 wants
as much ampereage from ballast output as "true F40" does.

While 32-watt and T8 version of F30 and the "25 watt look-alike of
F40T12" are in one lower level of ballpark in ampereage desired to flow
through them.

(Though 34 watt look-alike of F40T12 needs most ampereage of anything
mentioned above, and is also a "crankier" bulb that needs at least as much
voltage to start as anything mentioned above- though can be run at voltage
only a little higher than that needed to run F30T12 - once the
"often-cranky" 34 watt version of 4-foot T12 gets started and warmed-up.)
--
- Don Klipstein (d...@misty.com)

Don Klipstein

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Nov 1, 2010, 1:22:16 AM11/1/10
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In <9a090ecc-fcfd-49f1...@26g2000yqv.googlegroups.com>,

Use only a combo of bulbs and ballast(s) overtly rated for your combo
on the ballast label or overtly rated "as OK" ("my words") in writing by
the ballast manufacturer/supplier.

Color/spectrum variantions do not matter. Wattage and length/diameter
variations *do* matter.

If the bulb diameter and/or rated wattage changes, then you need to
have your ballast(s) overtly rated to be compatible with such and wired
in accordance with a wiring diagram by the ballast manufacturer said by
the ballast manufacturer to make the ballast "good/rated" for your "lamps"
(bulbs), including compliance with a ballast-mfr-stated wiring diagram
for your ballast and your lamps / "bulbs".

Andy

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Nov 1, 2010, 4:40:26 PM11/1/10
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On Nov 1, 12:22 am, d...@manx.misty.com (Don Klipstein) wrote:
> In <9a090ecc-fcfd-49f1-b637-a9f1bfa9c...@26g2000yqv.googlegroups.com>,

I found the answer and shoplight is going.

The box was marked "Use only T-12 bulbs" when in reality it required
the T-8 bulbs.

The insert did not list what bulb it needed at all.

The light output is more white and natural than the fatter tubes.

Andy

E

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Oct 26, 2020, 3:31:29 PM10/26/20
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Thanks for the posts. At my office I allowed the local utility company to come in and make modifications so that the 4" lights would take T12 bulbs instead, ostensibly to save $. Can I still use the F40 in them?

--
For full context, visit https://www.homeownershub.com/maintenance/f40-cw-bulbs-with-t12-ballasts-601242-.htm

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