Electical Concerns

serpentman

part time superhero
As cold weather approaches, I am concerned about my electrical system. I have been skirting the "razor's edge" all summer with the new lighting (~1300W total). Several times I have blown the main breaker when running too many appliances, etc.

Because our home is all electric, although it looks like the furnace is run on a subpanel, I am concerned about the demand due to an electric furnace. Future plans include a dedicated subpanel for the tank.

In the meantime, should I be concerned? Does anyone know a good electrician?
 
How many amps is the Main? You may need to increase your service if you are blowing the main breaker all the subpanels in the world won't aleviate that problem
 
just did the math and your lighting is pulling 15.6 amps if you give me the watt ratings of the rest of your equipment I can give you your total system amperage
 
Jeff,
If you look at the "main" breaker it should say the total amp rating of your breaker panel. Mine, like most modern houses, has a 200 amp service. If you are worried that you will overload the entire service, that will be very hard to do. If you are just worried about the draw you are putting on the one leg running your lighting, I would understand your concern and would recommend running them on 2 different circuits if possible.
To figure amp draw you can divide the wattage (1300w) by the voltage(120v). So your 1300w of light is drawing almost 11A already. If you have a 15A circuit then you are getting close to the recommended 80% maximum as it is (max recommended would be 1440w). If you have a 20A circuit then you are OK as long as not much else is being run off that leg.
For my fishroom area I ran a small subpanel with 2 dedicated 20A circuits. It cost about $75 in parts but I had to run the wire about 40 ft away. If you are closer to the breaker box then you will save money on wire.
If you wanted to DIY this project I could give you a hand but I am in no way a licensed or bonded electrician. I am just an experienced fixer-upper :)
You should make the trip out here sometime to check out my setup and see if you would like to do something similar at your place.

-- Kevin

Oh yeah, one other thing I recommend is to run some of your pumps/powerheads and some lighting and heat on one circuit and the rest of the pumps/lights/heat on another. That way if you ever have a breaker trip and you are not around to see it immediately you will still have circulation, light and heat which should be able to sustain your livestock until you find the problem. (think of it as a solar eclipse or a very cloudy day in their natural environment)
 
I suspect I may need to upgrade my service. To follow is a picture of my breaker box. There is a breaker labelled "Main Select" which is 2x50A clipped together. I suspect this means my house (built in 1979) is only wired for 100A? Assuming nothing changes from now on, will I run into trouble when the furnace starts coming on?

99.9% of the time, it is one of these 50A breakers that trips. For example, one tripped last night when someone plugged the iron in downstairs on Circuit #2.

breaker.jpg


The tank is wired across 2 circuits but 1 carries most of the load:

Circuit 1 (dedicated 20A):

Main Circulation pump: 350W
Heaters: 500W
Refugium Lighting: 80W
Frag Tank Light: 130W
Fan: 40W
PH: 3x 40W= 120W
MHs: 400W+250W=650W

Circuit 2 (20A)
MH: 400W
PC Lights: 200W
Misc Household: ?

Kevin,

I would like to take you up on your offer and look at your set-up. Are you planning on going to the frag swap on Sat? Perhaps we can car-pool, I can drive.
 
You have a total load on the fish tank with everything on at once of 25 amps, there is no way a full electric house should be on 100 amp service, are you sure what is marked as the furnace is not actually the Main?
I am electrician where I work but work under there bonding and license and can't pull permits on my own, and in fact if you only have 100 amp service you are in dire need of an upgrade, circuits 1&3 and 2&4 are meant to be single 220 vac set ups and should not be 4 110vac branches.
Let me know how I can help
I would love to see a pic with the cover removed
 
Here is a picture of the box with the cover removed. I did verify that the 100A breaker is not mislabeled. There is a separate subpanel that was installed when I had the furnace replaced. It has breakers for both the furnace, electronic filter and AC.

If I have to upgrade, ballpark, what kind of $ should I expect? We are looking at selling the house soon so it may or may not be justified. Also, if I don't, short-term is there any danger? Finally, with the furnace wired to a sub-panel, is there a chance it will overload with the tank running?

DSCN1840.jpg


On another note, I closed our pool today, so I won't be running the pool filter (8.8A continuously running). You should see my electric bill!
 
What brand of panel is that? It appears that it is divided into (2) sections. The bottom section appears to be supplied by the double pole 50A breaker(the "main select"). The top section (with the furnace, dryer, etc) appears to be fed directly from the service bus.

Important Questions:

Is there a main breaker or service disconnect at your meter socket?

If you throw the "main select" breaker, does it kill the furnace, dryer, water heater and oven also?

Ther is NO WAY a double pole 50A breaker is supplying Electric Water, Heat and an Oven all at the same time, let alone the dryer and the rest of the house.

Bean
 
The panel is a "General Electric". When I throw the "Main Select", it does not shut off the breakers above it (i.e. Water heater, oven, furnace, etc.). Basically, all the outlets and lights are effected.

There is a disconnect on the furnace sub-panel. However, there is no visible main breaker or service disconnect at the meter. If there is one, it is hidden in the meter box.
 
Can you get a model number off of the panel. Can you get the specs off of hte service entrance cable (the cable the feeds the panel?)

You at this point have (5) basic choices.

1) Put a breaker above the "main select" to feed the fish tank (or move one of the others up there).
2) Replace hte main select breaker with a larger one (this will depend on the panel rating, and the rating of the jumper wires that connect that breaker to the bus.
3)Run the fish (or move other circuits) to the FURNACE sub panel.
4)Install a new SUBPANEL and move one of the other big breakers to the sub panel. Feed the SUB with the newly opened spot.
5)Replace the Panel (and possibly the service entrance cable) with a 200A panel.

I am concerned that there is no MAIN breaker or service disconnect. Are you sure that the service entrance cable runs straight from the meter socket to that panel?
 
Heres the deal...

That SPLIT BUS panel is no longer allowed by the NEC (as far as I know). It is grandfathered of course. If I were you, I would replace it with a suitable new MAIN DISCONNECT panel. The idea back then was to procide heating loads at the top (electric house) and then the lower section was for lighting and standard domestic loads. The 50A main is hard to replace and most folks now have the same problem... the bottom bus is way overloaded.

It appears in the 60's and 70's those panels were populer. They allowed 6 breakers to be installed above the sub bus. In any case it may be best to just replace the panel and ensure that you make it one of the selling points ("new electric service").

Bean
 
here is the stuff from the NEC that relates to this situation:

408.16 Overcurrent Protection.
(A) Lighting and Appliance Branch-Circuit Panelboard Individually Protected. Each lighting and appliance branch-circuit panelboard shall be individually protected on the supply side by not more than two main circuit breakers or two sets of fuses having a combined rating not greater than that of the panelboard.
Exception No. 2: For existing installations, individual protection for lighting and appliance branch-circuit panelboards shall not be required where such panelboards are used as service equipment in supplying an individual residential occupancy.

Comment from the NEC Handbook:
The phrase “for existing installations” in Exception No. 2 refers to the existing panelboard. It is not intended that a split-bus panelboard used in an individual residential occupancy be replaced if a circuit is added to the existing panelboard. It does mean, however, that for the installation of new panelboards in new or existing residential occupancies, a split-bus six-disconnect panelboard (with more than two circuit breakers or sets of fuses protecting the panelboard) is not permitted for the service equipment.
An individual residential occupancy could be a dwelling unit in a multifamily dwelling where the panelboard is used as service equipment. See the definition of dwelling unit in Article 100.
***************************
 
As you can see you are not required to replace it... but it would solve a LOT of your problems. If this simply is not in your budget squeeze one of the breakers in above the main or setup a subpanel or use hte furance subpanel as I already mentioned.

This is just friendly advice. You should consult an electrician (I am not one) if you have any doubts or questions.
 
Thanks Bean,

I am not sure which option to go with. I guess, I will have an electrician take a look and see which option is the most economically feasible. It will really depend on how long we plan on staying. Although its a good selling point, I have many capital projects under way! Short term, I may try out option 1.

Fortunately, taking the pool offline saves me ~1200W of continuous use as well.
 
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