Why is one outlet bigger?

One outlet socket is larger than the other, to protect you from unauthorized wiring, such as hair dryer, vacuum cleaner, and coffee maker.

Current trend

Swinging or twisting a plug is annoying to easily insert it into the correct socket of the outlet. However, there is a reason for the vertical teeth of the plug.

In order to protect the safety of operating daily electrical products such as hair dryer, food processor, vacuum cleaner, table lamp, etc., the outlets large and small grooves and plug protrusions are designed.

The reason why the outlet looks like a face

The two outlets on the round holes may look like a surprising emoticon, but this shape is a national standard for sliding the plug comfortably and reliably to the outlet.

In the United States, the 120 bolts outlets have two vertical sockets, with round holes in the center just below. The right or hot socket is slightly smaller than the left or neutral socket towards the outlet with the round hole. A small hole is for earth grounding on a 3-pimp clag.

If there are only two large and small plugs, this is a polar type. However, as is common in bulbs and other small electrical products, it does not contain ground teeth.

1 Reasons why programs are large

In the no n-ground type polar plug, one foot (neutral) is larger than the other, and the smaller legs are hot wires. The electricity flows through the circuit. A circuit is a closed route of parts flowing from the current source.

To briefly explain things, the power of the outlet flows from hot to neutral. When the plug is inserted into the outlet, the circuit from the hot socket to the neutral socket is completed, and the electricity flows safely from the electrical system at home. This quickly supplies the current that starts motor, filament, coil, and other elements.

2 or 3 units 3 outlets

The main difference between a 2-pin and a 3-pin outlet is the ground line. The outlet ground line has two important roles.

In the case of electrical appliances and equipment surrounded by metal, such as refrigerators and washing machines, metal cases and frames are connected to the equipment ground wire of the power cord cord.

This equipment grounding conductor is connected to the ground path of the receptacle outlet and then to the equipment ground conductor of the branch circuit wiring back to the main electrical panel. There, the equipment grounding conductor is connected to the home's grounding system and to earth. This means that under normal operating conditions, the appliance is "grounded" and should not pose a shock hazard.

However, if the hot wire inside the appliance breaks and touches the metal frame or case, it creates a dangerous ground condition and poses a shock hazard. The equipment ground conductor then passes an excessive ground fault current to the main power panel, which blows a fuse or trips a breaker to cut off the flow of electricity.

All of this happens in a split second, preventing a shock hazard.

Two-prong sockets

Two-prong sockets were the standard in homes built before the 1960s. Although they are not grounding types, they are still safe to use as long as they function properly according to the National Electrical Code. Test your two-prong outlets with a circuit tester to make sure they are safe to use for small appliances and other everyday items.

3-prong mounting plugs cannot be used with 2-prong receptacles. Never disconnect the ground on a 3-prong plug. There is a risk of electric shock.

2-prong sockets pose the following hazards:

• Electrical fires
• Electrical fires?
• Electrical fires?

However, if properly wired and in working order, a 2-prong ungrounded socket itself is not a hazard.

Most of the danger comes when someone tries to use a 2-prong plug incorrectly. It is fine for cell phone chargers, table lamps, and other 2-pronged devices, but not for 3-pronged devices. There are many "adapters" on the market, but they can pose a serious shock hazard if used incorrectly.

3-prong sockets

3-prong outlets have a ground wire to prevent dangerous electric shock and fire. If the hot wire of the coffee maker is loose inside the metal-sheathed body, the metal sheath will trip. Touching a running coffee maker can pose a fatal electric shock hazard to anyone nearby.

Kimberly McGhee

Kimberly McGee is an award-winning journalist based in Las Vegas. She specializes in health and wellness, food, travel, real estate, home improvement, and interior trends. Her articles have appeared in The New York Times, The Los Angeles Times, People, The Las Vegas Review-Journal, Today's Parent, and many other publications. McGee is able to create a variety of C.

PostgreSQL Replication Slots: A Comprehensive Data Analysis

PostgreSQL replication slots are a critical feature that ensures that a master server maintains the necessary write-ahead logs (WAL) even when a replica is temporarily disconnected. In a streaming replay scenario with hot and archive queues, the replay slots hold the WAL files so the master can monitor the queue lag. When the waiter reconnects, the held WAL files are decoded and applied.

Table of Contents

This article highlights the importance of PostgreSQL replication slots, describes their types, and provides commands to create, delete, and monitor PostgreSQL replication slots. Learn more about PostgreSQL replication slots and implement them effectively! What is a Replication Slot?

Replication slots are a PostgreSQL feature that ensures that a master server maintains the WAL logs required by replicas even if it is disconnected from the master.

When streaming replication is used between a master server and a specific centralized standby or archive server, replication slots are needed to maintain WAL files even if replicas are offline or disconnected.

When a standby is disconnected, the master can monitor the standby's lag time and maintain the required WAL files until the standby is reconnected. The WAL files are then decoded and replicated to the replicas.

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When you have a master and several hot standbys or archive queues and are running streaming replication between them, replication slots are used to maintain WAL files even if replicas are offline or disconnected.

The ability to connect to a server and run read-only queries while it is in file recovery or standby mode is called "hot standby". This is important not only for replication, but also for restoring a backup to a specific state with great accuracy. The term "hot standby" also refers to the ability of a server to switch from recovery to normal operation while users continue to run queries and maintain open connections.

This feature was introduced in PostgreSQL 9. Prior to that, the master had to keep a set of WAL files if it went offline until the standby came back online. This is done by setting wal_keep_segment correctly, or high enough that copies are not left behind too much.

If this is not done, the standby will not be able to catch up with the master, as the master will delete WAL files that the standby has not yet replicated, resulting in an error:

ERROR: requested WAL segment 00000049000067B00000073 has already been deleted.

The problem with setting the correct wal_keep_segment is that it is difficult to know exactly how many WAL files to keep. This is guesswork, and if you set it too high, the master will run out of space in the pg_wal directory (WAL files are stored in the pg_wal directory; before version 10 they were stored in the pg_xlog directory).

Alternatives to the above method are either to archive the WAL, i. e. you have to write a script to move the WAL files to another long-term location, or to create a standby that stays up from the beginning.

After the advent of replication slots in PostgreSQL 9. 4, you don't need to worry about wal_keep_segments. If the standby goes offline, the master can monitor how far behind the standby is and hold onto the necessary WAL files until the standby reconnects. It can then decode the WAL files and replay them to the replica.

Get a database replication checklist

PostgreSQL replication port types

There are two types of replication slots in PostgreSQL:

PostgreSQL physical replication locations

• PostgreSQL logical replication slots
• PostgreSQL physical replication slots

PostgreSQL logical replication slots

This creates a physical replication slot on the master server, where transactions are transmitted in the standby mode. The master server holds these WAL files, even if the standby state loses the connection.

PostgreSQL logical replication location

The logical replication was introduced in PostgreSQL 10. Logical replication only brings changes like SQL. It does not work without a replication slot. Logical replication data must be decoded using plu g-in.

Hevo sets the Wal for the logical replication of the pipeline. See this document for the procedure.

How to create a PostgreSQL playback slot

To create a physical replication slot, use the pg_create_physical_replication_slot function. This command must be executed on the master node.

Here, create a replication slot named "Ocean".

Postgres =# select pg_create_physical_replication_slot ('ocean'); Like. The master server holds these WAL files, even if the standby state loses the connection.

PostgreSQL logical replication location