Wiring septic system

[iwirehouses]

I searched every thread here and it seems like there are many perspectives on the correct way to do this. My previous experience with septics is with ellaborate systems. The pump installer runs the conduit, wires, and terminations inside the tank. I walk in, pipe the conduit over the the control panel, terminate the wires, and feed the panel (220, 30A). I've never been inside the tank doing electrical. Until now...


This system is a 110 line out to the pump, and a 9v circuit controlling the little dinky alarm which is plugged into an outlet inside. I see theres much debate upon wether or not you can run the 110 an 9v in the same counduit. Also much debate on wether you put a j-box in the tank, or on a post above ground. Can anyone clarrify this?

Would it be easier to run it all in UF? A 12/2 for the 110v pump and a 14/2 for the 9v alarm? That way they're not in the same conduit? I hate using UF. I think conduit is much more professional.

 

[mcclary's electrical]

I searched every thread here and it seems like there are many perspectives on the correct way to do this. My previous experience with septics is with ellaborate systems. The pump installer runs the conduit, wires, and terminations inside the tank. I walk in, pipe the conduit over the the control panel, terminate the wires, and feed the panel (220, 30A). I've never been inside the tank doing electrical. Until now...


This system is a 110 line out to the pump, and a 9v circuit controlling the little dinky alarm which is plugged into an outlet inside. I see theres much debate upon wether or not you can run the 110 an 9v in the same counduit. Also much debate on wether you put a j-box in the tank, or on a post above ground. Can anyone clarrify this?

Would it be easier to run it all in UF? A 12/2 for the 110v pump and a 14/2 for the 9v alarm? That way they're not in the same conduit? I hate using UF. I think conduit is much more professional.

I agree with your outlook on UF, but I will admit I've done several the exact way you say. But, more often than not, I run two seperate conduits in the same ditch back to control panel inside. Of the last five I did, 2 were done by the plumbers w/ thwn. I did two with thwn, and one with uf setup. I think it depends on the situation and the soil.

 

[iwirehouses]

So you would need two junction boxes? One for the low voltage splice back to the house and one for the pump to plug into?

Whats the consensus on putting these boxes in the tank, near the top? From people I have personally spoken too, it seems like this is the norm.

 

[mcclary's electrical]

So you would need two junction boxes? One for the low voltage splice back to the house and one for the pump to plug into?

Whats the consensus on putting these boxes in the tank, near the top? From people I have personally spoken too, it seems like this is the norm.

You would need two seperate boxes, if low voltage is used. I'ved done several that had line voltage floats. that worked well because I only needed one conduit and box. I've installed them inside the tank occasionally. Most of the time I install a PVC box right on the side of the tank at grade level. I've seen metal boxes inside tanks fall apart from corrosive vapors, but I usually use PVC anyway.

 

[Dennis Alwon]

I have always run 2 cables. A 12/2 UF for the pump and 14/2 for the low voltage. I am quite surprised that they will allow this hookup in the tank with the methane gases that are in there.

That was the accepted practice here but that changed years ago. Now there is a special box that we mount at the septic pump on a 4x4 post. The wires from the pump and the float and alarm are sleeved in a piece of 2"pvc.

The pipe goes between the tank and the special alarm /control box.

 

[One-eyed Jack]

Question for all of you. Did any of you provide a separate power source for the alarm as required by the mf. ie the sewer lift pump and the alarm must be on two separate circuits regardless of voltage. Alarm must function if pump circuit trips.

 

[mcclary's electrical]

Question for all of you. Did any of you provide a separate power source for the alarm as required by the mf. ie the sewer lift pump and the alarm must be on two separate circuits regardless of voltage. Alarm must function if pump circuit trips.

Yes, that is required. I agree with Dennis on the boxes and vapors. I've seen several installions that used a metal box that was completely desinegrated

 

[Dennis Alwon]

Question for all of you. Did any of you provide a separate power source for the alarm as required by the mf. ie the sewer lift pump and the alarm must be on two separate circuits regardless of voltage. Alarm must function if pump circuit trips.

Absolutely. The alarm cannot and should not be on the same circuit as the pump.

This opens up some issues for those that believe that a 4x4 or the septic pump area is a structure.

Many of the alarm/controllers are designed for a 12/3 fed- one for the alarm and one for the pump sharing a neutral. This means that we must install a DP breaker or 2 sp with ties to satisfy the new requirement for MWBC.

This would mean if the pump goes out so to does the alarm which would defeat the purpose of the alarm.

So we have made the manufacturers of the alarm box set them up to accept 2 separate feds. Now there is a problem satisfying article 225.30 if we consider the tank as a structure. :-?

You can't win.:grin:

 

[One-eyed Jack]

Absolutely. The alarm cannot and should not be on the same circuit as the pump.

This opens up some issues for those that believe that a 4x4 or the septic pump area is a structure.

Many of the alarm/controllers are designed for a 12/3 fed- one for the alarm and one for the pump sharing a neutral. This means that we must install a DP breaker or 2 sp with ties to satisfy the new requirement for MWBC.

This would mean if the pump goes out so to does the alarm which would defeat the purpose of the alarm.

So we have made the manufacturers of the alarm box set them up to accept 2 separate feds. Now there is a problem satisfying article 225.30 if we consider the tank as a structure. :-?

You can't win.:grin:

Well,by gum I totally agree with you!!!

 

[augie47]

In this area there are two basic systems for single family residence.
In one area the wastewater folks supply a control box with the pump & alarm circuitry in place and the floats and pump cables are rated for direct burial. They are sleeved in conduit into the supplied box which is supplied by one circuit which is split by internal breakers.
Where the box is not supplied, the normal install is a 2" PVC from the pit to a PVC box mounted on a post with a receptacle inside (the pump plugs in thru a float adapter) and a j box for the LV cable. From the j box there are normally to UG conduits or UF back to the residence.

 

[iwirehouses]

I'll run two 3/4" conduits out to the tank. If I use a plastic box inside the tank, do I hardwire it, plug it into a weather proof receptacle, or plug it into a weather proof gfi?

 

[Dennis Alwon]

I'll run two 3/4" conduits out to the tank. If I use a plastic box inside the tank, do I hardwire it, plug it into a weather proof receptacle, or plug it into a weather proof gfi?

In my opinion the wiring should not be in the tank but if you did then I would do whatever was appropriate for the install. If the pump has a male end then I would install a recep. but not GFCI ( I believe we have an amendment for that) . If the floats and alarm have male ends then I would supply a recep for it as well. Otherwise a disco and direct wire would work.

 

[jeremysterling]

The last one I did, the control panel was 70' from the tank. The tank was in the front lawn, so a post with j-box would be unsightly. The plumber cored a hole for me after he made his hole. I sleeved the hole into a plastic box laying on top of the tank, which I then covered with a handhole. Then IMC over to the control panel.

As for the OP, either way sounds good to me.

 

[hardworkingstiff]

I would not install an outlet in the pit (where the pumps are housed). No recommended installation from the manufacturer?

I've always piped out of the pit with PVC to a box (on a post) adjacent to the pit.