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2 black wires but no white wire (photocell-controlled...

Author Message
J.R....
Posted: Tue Sep 01, 2009 1:49 pm
Guest
I have a condo porch light that's controlled by a master photocell on the
outside wall which also turns on other exterior lights at night. You can
turn the porch light on/off from inside the condo as well.

This porch light was removed/replaced years ago and now needs to be
reinstalled. The bulb type is a 2-Pin G23 fluorescent.

Confusion arises because the light's housing has two black wires but NO
white wire. It also has a green ground wire that appears to have not been
used in the original installation (end is still insulated).

The wall box has the typical one black and one white wire, with ground
apparently optional.

Can I hook one black to black and the other black to white? Or should I tie
both blacks to black and cap off the white box wire? Thanks for any
concepts.

J.R.
 
RBM...
Posted: Tue Sep 01, 2009 1:54 pm
Guest
"J.R." <jr_27 at (no spam) ewing.com> wrote in message
news:578ec$4a9d7ac3$407162f2$1381 at (no spam) EVERESTKC.NET...
[quote:21f862d5f8]I have a condo porch light that's controlled by a master photocell on the
outside wall which also turns on other exterior lights at night. You can
turn the porch light on/off from inside the condo as well.

This porch light was removed/replaced years ago and now needs to be
reinstalled. The bulb type is a 2-Pin G23 fluorescent.

Confusion arises because the light's housing has two black wires but NO
white wire. It also has a green ground wire that appears to have not been
used in the original installation (end is still insulated).

The wall box has the typical one black and one white wire, with ground
apparently optional.

Can I hook one black to black and the other black to white? Or should I
tie
both blacks to black and cap off the white box wire? Thanks for any
concepts.

J.R.
[/quote:21f862d5f8]
If you are sure that there are only the two black wires on the fixture, plus
ground, then connect either one to the black wire in the box, and the other
to the white, connect grounds together
 
J.R....
Posted: Tue Sep 01, 2009 1:58 pm
Guest
"J.R." <jr_27 at (no spam) ewing.com> wrote in
news:578ec$4a9d7ac3$407162f2$1381 at (no spam) EVERESTKC.NET:

[quote:81107798d9]Can I hook one black to black and the other black to white? Or should
I tie both blacks to black and cap off the white box wire?...
[/quote:81107798d9]
Addendum:

I realize that tying both blacks to black would not logically allow current
flow unless part of the fixture is tied to neutral, which I see no evidence
of. Just taking a wild guess with that.

I've read that some black wires have a faint white stripe and are actually
neutral, but I don't see such a stripe. They are also identical in surface
texture.

J.R.
 
J.R....
Posted: Tue Sep 01, 2009 2:03 pm
Guest
"RBM" <rbm at (no spam) noemail.com> wrote in news:4a9d7bdc$0$22513$607ed4bc at (no spam) cv.net:

[quote:dbc3f32fbc]
"J.R." <jr_27 at (no spam) ewing.com> wrote in message
news:578ec$4a9d7ac3$407162f2$1381 at (no spam) EVERESTKC.NET...
I have a condo porch light that's controlled by a master photocell on
the
outside wall which also turns on other exterior lights at night. You
can turn the porch light on/off from inside the condo as well.

This porch light was removed/replaced years ago and now needs to be
reinstalled. The bulb type is a 2-Pin G23 fluorescent.

Confusion arises because the light's housing has two black wires but
NO white wire. It also has a green ground wire that appears to have
not been used in the original installation (end is still insulated).

The wall box has the typical one black and one white wire, with
ground apparently optional.

Can I hook one black to black and the other black to white? Or should
I tie
both blacks to black and cap off the white box wire? Thanks for any
concepts.

J.R.

If you are sure that there are only the two black wires on the
fixture, plus ground, then connect either one to the black wire in the
box, and the other to the white, connect grounds together
[/quote:dbc3f32fbc]
Seems logical, but there's no evidence ground was originally used; an
oversight on the installer's part maybe.

J.R.
 
RBM...
Posted: Tue Sep 01, 2009 2:41 pm
Guest
"J.R." <jr_27 at (no spam) ewing.com> wrote in message
news:20a7f$4a9d7e24$407162f2$1444 at (no spam) EVERESTKC.NET...
[quote:8313359799]"RBM" <rbm at (no spam) noemail.com> wrote in news:4a9d7bdc$0$22513$607ed4bc at (no spam) cv.net:


"J.R." <jr_27 at (no spam) ewing.com> wrote in message
news:578ec$4a9d7ac3$407162f2$1381 at (no spam) EVERESTKC.NET...
I have a condo porch light that's controlled by a master photocell on
the
outside wall which also turns on other exterior lights at night. You
can turn the porch light on/off from inside the condo as well.

This porch light was removed/replaced years ago and now needs to be
reinstalled. The bulb type is a 2-Pin G23 fluorescent.

Confusion arises because the light's housing has two black wires but
NO white wire. It also has a green ground wire that appears to have
not been used in the original installation (end is still insulated).

The wall box has the typical one black and one white wire, with
ground apparently optional.

Can I hook one black to black and the other black to white? Or should
I tie
both blacks to black and cap off the white box wire? Thanks for any
concepts.

J.R.

If you are sure that there are only the two black wires on the
fixture, plus ground, then connect either one to the black wire in the
box, and the other to the white, connect grounds together

Seems logical, but there's no evidence ground was originally used; an
oversight on the installer's part maybe.
[/quote:8313359799]
No time like the present, to do the right thing.
[quote:8313359799]
J.R.[/quote:8313359799]
 
J.R....
Posted: Tue Sep 01, 2009 3:16 pm
Guest
"RBM" <rbm at (no spam) noemail.com> wrote in news:4a9d86bb$0$10286$607ed4bc at (no spam) cv.net:

[quote:076452403b]Seems logical, but there's no evidence ground was originally used; an
oversight on the installer's part maybe.

No time like the present, to do the right thing.
[/quote:076452403b]
So, this looks like a case where black vs. white is arbitrary? Common
practice with fluorescent bulbs?

I'm trying to figure out the general wiring concept. The condo was built
around 1970.

J.R.
 
RBM...
Posted: Tue Sep 01, 2009 4:30 pm
Guest
"J.R." <jr_27 at (no spam) ewing.com> wrote in message
news:dd968$4a9d8f30$407162f2$10906 at (no spam) EVERESTKC.NET...
[quote:a2ab23f911]"RBM" <rbm at (no spam) noemail.com> wrote in news:4a9d86bb$0$10286$607ed4bc at (no spam) cv.net:

Seems logical, but there's no evidence ground was originally used; an
oversight on the installer's part maybe.

No time like the present, to do the right thing.

So, this looks like a case where black vs. white is arbitrary? Common
practice with fluorescent bulbs?

I'm trying to figure out the general wiring concept. The condo was built
around 1970.

J.R.
[/quote:a2ab23f911]
I would think it has more to do with the fixture than the condo. It's
possible that the fixture works on multiple voltages, which may explain not
having a white wire. It may also be from a foreign country
 
 
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