Exterior Light wiring entry to house


  #1  
Old 04-04-15, 03:16 PM
A
Member
Thread Starter
Join Date: Jul 2002
Location: Ca
Posts: 747
Upvotes: 0
Received 1 Upvote on 1 Post
Exterior Light wiring entry to house

Hi,

I installed a post light using 1/2" pvc piping with THWN wiring. I would like to install a photocell but I don't really want to install it on the post. I would rather install it on the box where it enter the house. My photo cell requires a 5/8" hole for the sensor and the body of the sensor (inside box) is about 1" deep. I will be running the wire into my garage where I have romex coming from the breaker panel.

So my questions are-

1. Using a Type LB box to run through my garage wall, do I make the connection from THWN to romex inside the LB box?

2. I would like to install the photocell in the box. However, a type LB box may be too small. Can I use an FSE(single entrance, single gang) box? I would have to drill a hole in the back of the box to run the romex inside and use a blank plate but I don't know if this meets code. I don't see why not as an existing metal box on my house has a hole in the back for the wires (no nipple). If not I suppose I could use an FSC(double entrance) box to house the sensor and then run conduit to the LB box to enter the wall.

3. When using these boxes I noticed they don't really have any method of securing them to the wall. I noticed an existing metal box on my house has external ears for screws. Can you just run screw through the inside of the box?

Thanks
 
  #2  
Old 04-04-15, 03:50 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 64,939
Received 3,951 Upvotes on 3,544 Posts
The majority of the better FS boxes comes with two tabs that screw in to the back of the box for mounting. They have at least one threaded hole on each narrow side and one in the back.

That light sensor is designed to be installed in a post. You may have a problem installing it thru an FS box. They make sensors that will actually screw into a 1/2" threaded hub.

You conversion from THWN should be done in the FS box.

Name:  fs box.jpg
Views: 2401
Size:  41.5 KB
 
  #3  
Old 04-04-15, 04:38 PM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 5,074
Received 161 Upvotes on 147 Posts
This might be a better option for a photo cell.
Shop Utilitech Button Style Wall Plate Photo Control at Lowes.com
Geo
 
  #4  
Old 04-04-15, 05:25 PM
A
Member
Thread Starter
Join Date: Jul 2002
Location: Ca
Posts: 747
Upvotes: 0
Received 1 Upvote on 1 Post
Thanks,

I will get that plate style sensor. What I don't understand on the post style sensor shown below is that I don't see how you can get a water tight seal with a flat mount sensor on a round post. That and I don't really want to drill my post.


The box shown in the posting above appears to be metal and looks exactly like an existing one I have on my house. Can I use a metal box with 1/2" pvc pipe?

Can't really change the pipe at this point.

Name:  photocell.JPG
Views: 515
Size:  23.4 KB
 
  #5  
Old 04-04-15, 06:33 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 64,939
Received 3,951 Upvotes on 3,544 Posts
Use can use PVC or EMT with that diecast metal box.

The photocell doesn't seal well to the post in the post light because it doesn't need to.
 
  #6  
Old 04-05-15, 06:57 AM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 5,074
Received 161 Upvotes on 147 Posts
  #7  
Old 04-05-15, 02:25 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 13,976
Received 194 Upvotes on 170 Posts
The LB can only be used for a splice if the cubic inch capacity is given. Most are not marked. Even so if it were marked it is a pain.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: