Point of sale systems, commonly found in retail establishments and known as POS, often feature a complex arrangement of hardware, software and network connections. POS systems rely on predictable operation, and any number of problems can appear when hardware, software or users do not perform as expected.
Point of sale systems often involve an array of devices connected with one another using physical cables or secured wireless protocols. Typical POS components include workstations with screens and keyboards, bar-code scanners, check readers, display screens, cash drawers, receipt printers, customer-facing displays and remote data scanning devices, according to the POS hardware company Retail Systems. When one of these devices fails, the entire system may stop working correctly. If a printer fails, for example, the system cannot produce a transaction receipt and will stop processing transactions altogether. Many POS systems also include a central server that processes data and coordinates system-wide activity. These servers can experience all of the problems, like hard drive and memory failure, commonly associated with personal computers.
Just as POS systems rely on computer-like hardware, they also rely on computer operating systems and special software to perform point of sale functionality. Central servers and checkout workstations often run operating systems similar to those found on personal computers, according to Retail Systems. POS equipment also uses software applications to handle credit card processing, inventory tracking, accounting and other sales-related functions. When POS software encounters an error, or when too much software overloads the computer processor or memory, the system can stop working.
When a customer presents a credit or debit card as payment, the point of sale system must transmit the account information to the credit card processing network. According to the Merchant Account Guide website, POS systems usually rely on either dial-up modems or broadband Internet services to connect to the processing network. If the network connection becomes unavailable, the system will lose the ability to process credit and debit transactions; some systems may also lose the ability to verify check payments. In addition, dial-up connections must have clear audio to communicate with the credit card network properly. If any static exists on the line, the POS system may lose the ability to process credit, debit and check transactions.
Because of the complexity of point of sale systems, retail users must receive extensive training on how to perform transactions and operate the system, according to the entrepreneurial website More Business. If a user enters incorrect information or launches the wrong application, POS systems may become unpredictable or fail to process transactions correctly.