Can a subpanel feed another sub panel, and how to install one?
Make a list of all the things you plan to use in your home.If the Main Service or the Panel that will supply the Sub-Panel Circuit have adequate Load Capacity and space for the needed circuit breaker, that's an important factor.How big should your panel be?You should consider the circuits to be served by the Sub-Panel including general purpose electrical outlets and any special equipment which will be needed.Large 220 Volt loads such as Welders, Air Conditioners, Motor, Well Pumps and the like may require larger size wire and conduit to provide the necessary current.List all the requirements for the label.The longest distance from the power source is over 175 feet.An increased size of the wire and conduit is required for a 2% Voltage drop factor.Select the right box for your application if you need a 4-wire system.
The storage building where the sub panel was installed is about 150 feet from my home.I fed the sub panel with a cable.I am feeding 2 to 20 Amp circuits with #14 wire from this sub panel.With nothing but the fluorescent lighting on, I pull about 2.7 Amps of current with a measured voltage of 125 volts on this feed.When I turn on my shop vac, I am pulling about 11 Amps of current, and my measured voltage on this circuit drops to 118 volts.This causes my fluorescent light bulbs to stop working.Is the voltage drop enough to cause this problem?
When planning the wire size for a sub panel, or any panel for that matter, it is important to factor in the length of the distance from the source to the panel and the amount of power needed for it.The size of the sub panel will be determined by the circuit loads placed on it.Everything starts with planning the load that will be placed on the sub panel, and then we calculate the wire size feeding the panel based upon the distance.Due to the starting load, it is important to factor in any electric motors that may be used.