Security wire wall termination, junction box, or plug

[nwagner]

I'm creating a power sensing module using a relay to monitor a specific garage circuit that frequently trips the breaker during rainy weather. The security wire running from the relay will need to pass through my garage wall and into the basement. Is it better to simply pass the wire through the wall and straight to the module (which will be placed in a cabinet), wire it to a junction box, or is there a termination plug I could use to make it removable from the wall?

 

[pete_c]

a specific garage circuit that frequently trips the breaker during rainy weather.

 
Personally I would look for the issue relating to the breaker tripping during rainy weather.  I have historically replaced a couple of weak / bad breakers.
 
In the 1980's did find by accident a "live" HV metal conduit in the detached garage.  It lead me to redoing the electric chase from the house to the garage.

 

[nwagner]

Good point. It's a GFI that trips when I have outdoor lights on (around now cause of the holidays). I want to know when it happens so I can dry things out as it may be awhile before I realize it's tripped.

 

[pete_c]

Yup; here utilize GFI's per outlet outside and separated circuits to their own breakers granularly.  (overdid it a bit). 
 
You could do a quick disconnect of the HV going to the GFI and check all of the wires on the other side maybe with a VOM?
 
Unrelated here had an old English car in the 1960's which would never run in the rain or just shut off when it rained.  The electrical system would shut down in the rain.

 

[mikefamig]

I recently ran a new 12/4 20 amp service to my pool area and installed a very expensive 20 amp gfci breaker in the load center. The first time it rained out the breaker opened. Shortly afterward I ran into my electrical inspector and questioned him about it. He advised me to remove the GFI breaker until the atmosphere dried up in later in the summer and then replace it (nod nod wink wink). I believe that there are some devices that are just not going to exist well on a gfi circuit in wet conditions due to the fact that there is a small amount of stray current leaking to ground in the device.
 
My Traeger pellet grill will trip a gfi outlet when the ingniter is starting the fire and it is damp out. I replaced the igniter and it had the same problem..
 
Mike.
 
Edit
 
I have to correct what I said above. The inspector did not suggest that i replace the gfi, that would be against code. To be accurate, what he said was that when he was working as an electrician it is what they would resort to to correct the problem.
 
Mike.

 

[nwagner]

I like the gfi being there for safety cause it trips when lights and plugs get wet. I just want to know when it trips so I can find the water problem and resolve it. My main question/concern is "how do you think I should make the connection through the garage wall to the relay module in the cabinet?"

 

[RAL]

My main question/concern is "how do you think I should make the connection through the garage wall to the relay module in the cabinet?"

 
Can you describe the relay module in more detail?  Does it have screw terminals, spade lug terminals, pig tail leads, or solder terminals?  For the low voltage wiring back to your security panel, I would just use screw terminals or spade lugs if possible.  Not sure why you want this to be removable, other than perhaps if you view this as something temporary.  

 

[nwagner]

I'm using a elk-912 relay in a project box I built, powered by a wall wart. Wire terminates into screw terminals in relay through opening in project box. I guess I wouldn't have to make the security wire removable from the wall. I just figured a plug or connection of some kind would be good to have so I could change the location from the wall if needed and perhaps provide a more professional look than a wire simply exiting the drywall. You thinking something like this? http://www.amazon.com/gp/aw/d/B003U46E1W/ref=redir_mdp_mobile/190-4401193-4501953

 

[pete_c]

You can also make it a bit portable on the sensor switch side using wireless if you want, keeping it to using just a wall wart for the 120VAC side of the relay.
 
Here I sort over did it with GFI's putting one in every power out box outside even though they go to one or two circuit breakers.
 
Followed the electrician's methodology here as he put one in every kitchen outlet.

 

[Del91574]

Personally, I would just extend the HV circuit that you are monitoring off the wall using a handy box extension or similar, then use a RIB and then run that wiring back to the panel. If you needed to supply enough room for interconnection, a chase nipple or similar to separate the wiring would be what I'd suggest, unless you can get an add-on box onto the side of the existing, then blank that half and bring the HV side out far enough for a RIB.
 
The 912's, while rated up to 120V for switching are not really designed to handle the amperage that exists on the circuit and would lead me to view it as a bad choice for the application.
 
The amount of hardware you have tied up on the wart and relay could better be used with a single RIB and be less clunky.

 

[nwagner]

I like the RIB relays, but how would you run the n/c or n/o wires back through the garage wall to the panel? Something scares me about having high voltage and low voltage lines in a module like that.

 

[tmbrown97]

I think DEL may have misunderstood your indended use of the relay - amperage is a non issue the way I understand your description because it would just be powered by the wall wart and it would open/close dry contacts with no real current tied to a zone - so I would guess?
 
I would just exit the wall with the security wire into your relay.  Security wire is rated for in-wall.  I wouldn't overcomplicate this.  It's a screw terminal that can be removed if needed, and/or spliced if you absolutely had to.  Any other connection points are ultimately potential failure points.  

 

[Del91574]

I read the original description missing a couple of points, but I still would go with a RIB rather than a wall wart plugged into the circuit. Cleaner.
 
The RIB is 100% isolated on the LV and HV side and the majority are rated for life safety applications, can't get safer than that. We have thousands of them out in the field on equipment that costs multiples of the M1.
 
Mounted on an appropriate box with divider or maintaining separation isn't that difficult.
 
Personally, I'd look at the cause of the GFI tripping first and fix that. Contrary to what Mikefamig says, an electrician removing it to "fix" the issue usually is a poor choice. In the case of a pool area, the usual problem is poor bonding and not enough of a grounding grid and pulling the GFI amounts to a bandaid on a poorly designed or executed installation.

 

[nwagner]

So you would mount the relay project box to the wall where security wire enters the garage? Then run the wall wart power to it from the cabinet? I think I could make that work.

 

[mikefamig]

Personally, I'd look at the cause of the GFI tripping first and fix that. Contrary to what Mikefamig says, an electrician removing it to "fix" the issue usually is a poor choice. In the case of a pool area, the usual problem is poor bonding and not enough of a grounding grid and pulling the GFI amounts to a bandaid on a poorly designed or executed installation.

DEL
 
I agree with you about finding the cause of the fault as the best solution but I think that in some cases it's not a bonding problem or bad installation. I think that sometimes it's the device/load that is plugged into an outlet or hardwired into the circuit that is causing the fault. In the case of my pellet cooker the heating element draws a lot of current and when it is damp outside it causes the gfi to trip. Couldn't it be that this is because the heating element is not isolated from ground well enough. The manufacturer suggests leaving the lid open on the cooker when it is cooling down so that it will dry out and not contain moisture.
 
In the case of the swimming pool I don't believe that I have a bad bonding grid. There are two copper rods in the earth at the main load center at the house and the in-ground pool walls are made of steel and the electrical system bonded to them on that end. The pump motor and outlets are also properly bonded. The pump motor still trips the gfi when it rains out.
 
I like the pellet cooker and use it in spite of this design flaw. The pool pump is a brand name pump, only a few years old and has a large gauge copper wire from it's case to the bonding grid. I think that GFI is a great thing but there are devices out there that are not perfect and life is full of compromise.
 
Don't get me wrong, I'd love to be proven wrong and get these devices to run properly but haven't been able to up to now. When the grill manufacturer and a professional licensed electrician told me that they had no cure I decided to live with it.
 
Mike.