What hardware do you need for a POS?
You need one thing: a computer, tablet or phone that runs your POS. Everything else, from a barcode scanner to a receipt printer, cash drawer or label printer, is worth adding when it solves a real problem in your shop.
| Hardware | What it is for | When to add it |
|---|---|---|
| Computer, tablet or phone | Runs the till | From the first day; one you own will do |
| USB barcode scanner | Adds items without typing | When typing starts to slow the queue |
| Thermal receipt printer | Prints receipts | When customers want receipts, or you want your KRA PIN on them |
| Cash drawer | Holds the cash and opens on cash sales | When you take a lot of cash |
| Barcode label printer | Prints barcodes and shelf labels | When many of your goods have no barcode |
What you do not need: a special “POS terminal”, ink, or hardware bought from your software vendor. Thermal printers print with heat on special paper, so there is no ink or toner to buy. Standard hardware from any supplier usually works, but test one of each with your system before buying for every till. For rough prices, see what a POS system costs in Kenya.
58 mm or 80 mm receipt printer: which should you choose?
Choose a 58 mm printer for a small counter with short receipts, and an 80 mm printer for a busy till, long receipts or a supermarket. Both use thermal paper; only the width of the roll differs.
| 58 mm | 80 mm | |
|---|---|---|
| Characters per line, on most printers | About 32 | About 48 |
| Rough price (varies by brand and supplier) | KSh 3,500–8,000 | KSh 6,000–15,000 |
| Speed | Usually slower | Usually faster |
| Cutting the paper | Usually a tear bar | Often an automatic cutter |
| Port for a cash drawer | Not always: check before buying | Common, but still check |
| Suits | Small shops, kiosks, salons | Supermarkets, hardware stores, wholesalers |
If you want a cash drawer, make sure the printer has a drawer port before you buy it. Buy paper rolls in the width that matches your printer; an 80 mm roll will not fit a 58 mm printer.
How do you connect a thermal receipt printer?
A thermal receipt printer connects to the till in one of four ways: USB, serial, Bluetooth, or through a printing helper installed on the computer. Which one you use depends on the printer, the device and the computer’s operating system.
USB, straight from the browser
Chrome can talk to many USB receipt printers directly.
- Plug the printer in, load paper and switch it on.
- In your POS’s printer settings, choose USB.
- Chrome shows a list of devices: pick the printer and allow it. Chrome remembers the choice.
- Print a test receipt.
On Windows, if the printer’s own driver is installed, Chrome may not be able to reach the printer directly. In that case, use a printing helper (below), which prints through the installed driver.
Serial (COM port)
Some printers connect with a serial cable or a USB-to-serial adapter. Choose serial, pick the port, and set the speed (the baud rate) to match the printer. Many printers print a self-test page showing their speed if you hold the feed button while switching them on; the printer’s manual will confirm how.
Bluetooth
Bluetooth printers suit tablets and phones, and counters where a cable is in the way. Chrome talks to Bluetooth devices using Bluetooth Low Energy, so not every Bluetooth printer will work from the browser: test the exact model, or ask the seller, before buying several.
Through QZ Tray
QZ Tray is a free printing helper you install on the computer. It lets the browser print to a printer that is installed on Windows or macOS, using the printer’s own driver.
- Install the printer’s driver and print a Windows or macOS test page.
- Download and install QZ Tray from its official website, and leave it running.
- In your POS’s printer settings, choose QZ Tray, then pick the printer by name.
- Print a test receipt. QZ Tray may ask you to allow the site the first time.
Use QZ Tray when direct USB does not work, or when other programs on the computer also print to the same printer.
Printing in Wave POS
In Wave POS, you set this up in the till’s printer settings: choose how the printer connects (USB, serial or Bluetooth from Chrome, or QZ Tray) and whether it takes 58 mm or 80 mm paper. Receipts carry your logo, your KRA PIN, your own header and footer, and a QR code for returns. A second printer can print large order tickets without prices, for packing or preparing orders. Receipts and labels shows what goes on each.
How do you connect a cash drawer?
A cash drawer plugs into the receipt printer, not the computer. When a cash sale is completed, the POS tells the printer to send a short pulse down the cable, and the drawer springs open.
- Plug the drawer’s cable, which looks like a telephone cable, into the printer’s drawer port. It is often labelled DK or “cash drawer”.
- If the printer also has a network socket, make sure the drawer is not plugged into that by mistake.
- Turn on opening the drawer for cash sales in your POS’s printer settings.
- Make a test cash sale: the drawer should open as the receipt prints.
Most drawers also have a key that locks the drawer, or opens it by hand when the printer is off. Keep the key with the manager, not in the lock. In Wave POS, the cash drawer opens for cash sales, and the drawer is counted at the close of every shift; cash drawer reconciliation explains the count.
How do you set up a barcode scanner?
Most USB barcode scanners need no setup at all, because they act like a keyboard. Plug one in, put the cursor in a text box, scan a product, and the barcode’s numbers appear as if they were typed, usually followed by Enter.
To test a new scanner:
- Plug it into a USB port and wait for the beep.
- Open Notepad or any text box, and scan a product. The numbers should appear, and the cursor should drop to a new line.
- Open the till, scan the same product, and check that it is added to the sale.
Wireless scanners with a small USB receiver work the same way. Bluetooth scanners can pair with a tablet as a keyboard.
1D or 2D scanner?
A 1D scanner reads ordinary barcodes, the stripes printed on packaged goods. A 2D scanner, sometimes called an imager, also reads QR codes and codes shown on a phone screen. To scan the QR code Wave POS prints on receipts for returns, you need a 2D scanner.
Do you need a barcode label printer?
You need a label printer if many of your goods arrive without a barcode: loose items, goods you pack yourself, clothes, hardware fittings, or anything you want a price label on. A desktop thermal label printer prints barcodes onto rolls of stickers.
- Direct thermal labels need no ribbon, but they fade with heat and sunlight. They suit goods that sell within a few months.
- Thermal transfer labels use a ribbon and last much longer. Choose them for stock that sits on the shelf for a long time.
- Label size. Set the label size in the printer’s settings on the computer to match the roll you bought, such as 40 × 30 mm or 50 × 25 mm.
Wave POS prints barcode and shelf labels with prices, in batches, so you can label many products in one go. Print one label first, and scan it back into the till before printing the rest.
Test-print checklist before you open
Before the first day of trading, run through this list on every till:
- Print a test receipt and check the logo, the shop name and the KRA PIN, and that nothing is cut off at the edges.
- Check that the paper width setting matches the printer: 58 mm or 80 mm.
- Make a test cash sale and check that the drawer opens.
- Make a test M-Pesa sale and check that the drawer stays shut.
- Scan ten different products, including one with a short barcode and one with a worn label.
- Print a barcode label and scan it back into the till.
- Switch off the internet and print a receipt, to be sure printing does not depend on it; see how offline POS works.
- Restart the computer and print again, to be sure the printer reconnects.
How do you fix common POS hardware problems?
Most hardware problems come from paper loaded the wrong way, a wrong setting or a loose cable. Check those three first.
| Problem | Likely cause | Fix |
|---|---|---|
| The printer feeds blank paper | The roll is in the wrong way round | Load it so the thermal side faces the print head. Scratch the paper with a fingernail: the side that marks grey is the thermal side |
| Text is cut off or wraps oddly | Wrong paper width or characters per line | Set 58 or 80 mm to match the printer: most use 32 characters for 58 mm and 48 for 80 mm |
| Strange characters print | Wrong speed on a serial printer | Set the baud rate shown on the printer’s self-test page |
| The printer is not in the list | Switched off, unplugged, or held by its Windows driver | Check power and cable, try another USB port, or print through QZ Tray |
| The drawer does not open | Cable in the wrong socket, or the drawer option is off | Use the printer’s drawer port, turn the option on, and check the drawer is not locked |
| The scanner beeps but nothing appears | The cursor is in another window or box | Click into the till and scan again |
| Items are added only after you press Enter | The scanner is not sending Enter after each barcode | Scan the “add Enter” setup code in the scanner’s manual |
| A form saves itself when you scan into it | The scanner sends Enter after the barcode | Fill in the other fields first, and scan into the barcode field last |
| Letters in barcodes come out in the wrong case | Caps Lock is on | Turn Caps Lock off |