Decoding Electrical Systems: Switchboard vs. Panelboard vs. Switchgear
The switchboard, panelboard, and switchgear are the devices for overcurrent protection of the electrical circuit. This article outlines the key difference between these three types of electrical system components.
What is a Panelboard?
A panelboard is an electricity supply system component that divides an electrical power feed into subsidiary circuits while providing a protective fuse or circuit breaker for each circuit in a common enclosure. It consists of a single panel or a group of wall-mounted panels. The goal of a panelboard is to split energy into different circuits. They are similar to switchboards, but the structure is the factor that sets them apart.
What makes panelboards different is that they are always mounted to the wall. The only possible way to access panelboards is through the front.The amperage of panelboards is much lower than switchboard and switchgear, 1200 Amp max. Panelboards are used for voltages up to 600 V. Out of the three electricity system components, panelboards are the cheapest and the smallest in size.
Applications of Panelboards
Panelboards are more commonly found in a residential or small commercial setting where the total electrical demand is not exceptionally high. Typical applications of panelboards are:
- Residential, commercial buildings, and small industrial facilities. In homes and offices, panelboards distribute electricity to different parts of the building from the main supply. They can distribute electricity to HVAC systems, lighting systems, or large electrical appliances.
- Healthcare facilities. In healthcare facilities, panelboards are used for all applications outlined above for residential and commercial buildings, along with medical equipment power distribution.
Based on the application, panelboards can be divided into several subtypes, including lighting panelboards and power distribution panelboards. The main panel, subpanel, and fusebox are all types of panelboards.
Panelboard Components
- Main breaker
- Circuit breaker
- Bus bars
What is a Switchboard?
A switchboard is a device that directs electricity from one or more sources of supply to several smaller regions of usage. It is an assembly of one or more panels, each of which contains switches that allow electricity to be redirected. Because it is an assembly, a switchboard can be upgraded at any point of service. A key aspect of switchboards is that they typically include overcurrent protection for their supply circuits and are ground-mounted. The components of the switchboard are meant to reroute power.
What differentiates switchboards from other electric systems described below is that a switchboard represents an assembly of components. The voltage rating of the switchboard systems is 600 V or less. Switchboards are accessible for service from the front and back. Switchboards adhere to NEMA standard PB-2 and UL standard -891. Switchboards have meters that display the amount of power that goes through them, but they do not have any automatic safety components.
Applications of Switchboards
Like panelboards, switchboards are used in commercial and residential settings, and, like switchgear, they are used in industrial facilities. Switchboards are used for rerouting power main distribution equipment.
Switchboards are more expensive than panelboards but cheaper than switchgear. The goal of switchboards is to distribute power between different sources. Types of switchboards include general-purpose switchboards and fusible switchboards.
Switchboard Components
- Panels and frames
- Protective and control devices
- Switches
- Bus bars
What is a Switchgear?
Switchgear combines electrical disconnect switches, fuses, or circuit breakers to control, protect, and isolate electrical equipment.
Switchgear differs from switchboard and panelboards because it comprises individual components. Devices that are switchgear parts are used to turn the power on and off.
Switchgear is used to de-energize equipment to allow work to be done and clear faults downstream. It's generally used in settings where a larger power supply needs to be divided among many different pieces of equipment, which are basically commercial systems of different voltages (low, medium, and high). Switchgear is equipped with components that ensure automatic safety.
Switchgear is the most expensive and most extensive compared to panelboards and switchboards. The voltage rating of the switchgear is up to 38 kV, and the current rating is up to 6,000A. Switchgear follows ANSI standard C37.20.1, UL standard 1558, and NEMA standard SG-5.
Finally, the switchgear can be used both outdoors and indoors. Types of switchgear include low-voltage, medium-voltage, and high-voltage.
Applications of Switchgear
Switchgear is mainly used to control power loads. Common applications of switchgear include:
- Powering and switching equipment, especially main distribution equipment (transformers, generators, power networks, etc.).
- Identification of a fault in an electrical circuit and timely interruption before overload
- Control of equipment in power plants and power generator stations
- Transformer control in utility distribution systems
- Protection of large commercial buildings and data centers
Components of Switchgear
- Draw-out breakers: using draw-out breakers with switchgear prevents shutting down the electrical system for maintenance.
- Power switch components: circuit breakers, fuses, etc. These components are intended to break the power in a circuit.
- Power control components: control panels, transformers, protective relays. These components are intended to control the power.
Cables for Panelboards, Switchboards, and Switchgear
- Switchboard SIS Cable is a flexible electric cable used in panelboards, switchboards, and switchgear. You can read more about this type of cable here.
- Panelboards can equip all electrical power cables, including SER, THHN, XHHW, and even NM-B.
- Switchboards can also use THHN and XHHW cables, as well as RHH/RHW-2 cables. In industrial settings, switchboards can use various industrial power and control cables, including Type W, Type G, and DLO.
- Switchgear can also use industrial power and control cables and USE-2 and RHH/RHW cables.