Tips in Knowing How Many Electrical Sub Panels You Need
What do you do when your main electrical panel is full? All the circuits are in use, the breaker trips and costs you an expensive service call, or worse yet, a short in the main panel might start a fire. The best solution is to add a sub panel with enough capacity to handle all your load needs. Have a professional do your electrical panel Installation. But how many circuits do you need? And what other requirements must be considered before installing one?
You may call us, Rush Electrical Service, right away, but here’s everything you need to know first:
Calculate the Whole House Electrical Load
You can use the following equation to determine your house’s electrical load, which is the total amount of current that all of your devices will draw at once.
Calculate the whole house electrical load (KW)
(Total Number of Light Fixtures x Watts per Light) + (0.5 for Overhead Lights and Miscellaneous Appliances) + (1 for Heat/AC Units) = Total Wattage of Electrical Load
Determine if sub panel Needed
If the calculated wattage is less than 80% of your current sub panel’s rating, then you do not need an additional sub panel.
If greater than 120% of your current sub panel’s rating and less than 250%, then consider installing a new sub panel with a larger capacity. If you wish to add circuits or power outlets but are unsure how many circuits are available in the existing panel, consult an electrician before beginning any wiring project.
Identify the Circuit Breaker Size for Each Electrical sub panel
The first thing you’ll need to do is identify the circuit breaker size for each electrical sub panel. This can be done by using this formula:
Amps = Watts / Volts.
In other words, amps (or current) is a measure of how much power you’re using at any given moment. To determine your wires’ amp rating, multiply their gauge by their length (in feet). For example, if you have a 100-amp circuit breaker and run two 14 AWG copper wires from one wall outlet to another room at 10 feet apart—that’s 1/8 mile or 0.125 miles total—the total current would be 100 amps (14 AWG x 0.125 miles = 125 A). That’s why it’s important not to exceed an amp rating per wire: If heat builds up inside the insulation from too much current passing through it, that can cause fires!
Calculate the Total Circuit Breaker Size for All Electrical sub panels
Now that you’ve determined how many sub-panels you need, it’s time to determine the total circuit breaker size for all your electrical sub panels. The total circuit breaker size is calculated by multiplying the total load by the number of circuits in each sub panel and adding it together. In other words:
- Total load = Amperage (amps) of each circuit
- Number of circuits = Number of electrical sub panels
For example: If there are two sub panels with a total load of 15 amps per panel, a total circuit breaker size would be 15 amps x 2 = 30 amps.
Compare the Circuit Breaker Size to the Main House Panel Capacity
You’ll want to compare the total circuit breaker size to the main house panel capacity. If the total circuit breaker size is less than the main house panel capacity, then you can install an electrical sub panel.
How Is an Electrical Sub Panel Wired? Tips for Safety Electrical Wiring
Electrical wiring is a crucial part of home renovations, but it’s also one of the most dangerous. Electrical wires can pose serious hazards if they aren’t installed correctly or if they’re installed in a sub panel that isn’t wired correctly. In this article, we’ll explain how to wire an electrical sub panel so you can get your home renovation off to a safe start!
Install the sub panel.
Let’s say that you have the main circuit breaker and wires in place; it’s time to install the sub panel. It is important that you install your sub panel in a dry and well-ventilated area. The National Electrical Code (NEC) also requires that electrical equipment be installed at least 18 inches above floor level unless it is installed on a concrete slab or similar surface with adequate structural strength to support both the weight of the equipment itself and any loads imposed by its use.
Next, ensure you follow all the manufacturer’s instructions when installing your new sub panel. If no instructions come with your sub panel, call the pros to help you right away.
Moving on: you’ll need to consider how many circuits you will have wired through the new box and choose one according to its capacity. In most cases involving residential wiring projects, it is advisable not to exceed 50 amperes per circuit because this will give you maximum safety benefits while keeping costs low by using smaller wire sizes than might otherwise be required if more current were being carried through each individual circuit within your home’s electrical system; however, if these restrictions concern you too much, then they may opt instead for one large panel capable of handling 125 amps total output from all four sides combined which would allow access later down the line should additional work become necessary.
You need to keep different circuits in mind: the 240-volt and 120-volt circuits.
Wiring a 240-volt circuit.
Test the circuit with a voltage tester, voltmeter, clamp meter, and circuit analyzer to ensure that the wiring is correct and that there are no shorts or open circuits. If you’re not sure how to do this yourself, contact your local electrician for help.
Wiring a 120-volt circuit.
Wiring a 120-volt circuit is a simple job. First, wire the black and white wires to the hot wires. Then, wire the red and black wires to the neutral wires. Don’t forget to wire the ground wire to the grounding bar. And last, wire the green wire to the ground bar.
We hope that we have helped you to understand how an electrical sub panel is wired so you can be prepared for any situation. Always remember that installing and wiring sub panels are something that professionals should do, so if you don’t know what you’re doing, call the pros immediately.
Call Rush Electrical Service right now if you need some sub panel installation service. We assure you that we’re the best at it; in fact, we’ve never dissatisfied a single client ever since we started doing sub panel installation.
Testimonials
