125kHz 
125kHz RFID Readers
L150-R 125kHz RS232 Desktop RFID Reader with Card Recess
The L150-R is the RS232 version of our angled 125 kHz desktop reader. The card recess keeps card presentation consistent, and each EM4100 or TK4100 read is sent to a DB9 serial port at 9600 bps by default, framed by STX and ETX. It suits kiosks, terminals and PC services that listen on a COM port.
- Frequency
- 125 kHz
- Cards / tags
- EM4100, TK4100, SMC4001 and EM4100-compatible cards and key fobs
- Interface
- RS232, DB9 connector
- Output
- 10-digit decimal card number
- Read range
- Up to 80 mm (depends on card and environment)
- ✓ Sample units for evaluation
- ✓ Output format confirmed for your software
- ✓ Private label & OEM options
- ✓ Reply within 1 business day
Why integrators choose the L150-R
- RS232 over DB9 — the cable set has a DB9 female connector for the host's serial port.
- 9600 bps default — 19200 and 115200 bps are selectable.
- STX/ETX framing — each read arrives as one message from 0x02 to 0x03.
- Card recess — the angled 110 × 80 × 26 mm body shows users where to place the card.
- Up to 80 mm range — EM4100, TK4100 and SMC4001 cards and fobs in under 200 ms.
- Status feedback — red LED on standby, green LED and buzzer on a good read.
Unattended points that read from a COM port
Self-service terminals such as visitor sign-in kiosks, canteen or locker terminals and equipment checkout stations need two things from a card reader. Users must know where to put the card, and the software must receive the number even when no text field is selected. The L150-R covers both: the recessed card area guides the card into place, and each read goes to an RS232 port that a background service can monitor.
Commissioning checklist
- Confirm the host COM port and open it at 9600 bps, or at 19200 or 115200 bps if the reader was ordered that way.
- Present a known card and check that one STX (0x02) … ETX (0x03) message arrives with the 10-digit card number.
- Keep the reader off metal panels and away from other readers; both reduce the up-to-80 mm range.
- Plan the 1450 mm cable run to the DB9 port, plus the 5 V DC power connection we confirm for your host.
- Test with the cards and fobs your users actually carry, not only with a demo card.
For the trade-offs between serial, USB and Wiegand links, see choosing an RFID reader interface. Other serial models are on the RS232 and RS485 readers page.
Moving from the USB version
The L150-U and the L150-R share the housing and the default 10-digit decimal format, so enrolled cards keep the same numbers when a site moves from keyboard input to serial. Only the host side changes: instead of a focused text field, your software opens the COM port. The H150-R is the 13.56 MHz MIFARE equivalent for mixed sites.
L150-R specifications
| Model | L150-R |
|---|---|
| Frequency | 125 kHz |
| Form factor | Angled desktop reader with card recess, RS232 (DB9) and USB cable set |
| Housing | ABS |
| Color | Black |
| Supported cards | EM4100, TK4100, SMC4001 and EM4100-compatible cards and key fobs |
|---|---|
| Card operation | Read-only (card ID number) |
| Read range | Up to 80 mm (depends on card and environment) |
| Read time | < 200 ms |
| Read interval | < 0.5 s |
| Interface | RS232, DB9 connector |
|---|---|
| Baud rate | 9600 bps (default); 19200 / 115200 bps selectable |
| Default output | 10-digit decimal card number |
| Frame | Starts with STX (0x02), ends with ETX (0x03) |
| Output options | Custom output format on request |
| Host | PC or controller with an RS232 (DB9) serial port |
| Indicators | Red/green LED (red = standby, green = card read) and buzzer |
| Dimensions | 110 × 80 × 26 mm |
|---|---|
| Weight | Approx. 175 g |
| Cable length | 1450 mm |
| Power supply | 5 V DC |
| Operating temperature | -10 °C to +70 °C |
| Storage temperature | -20 °C to +80 °C |
| Humidity | < 90 % RH |
Specifications of L150-R as supplied for the standard version. Read range depends on the card or tag, mounting surface and environment — we can test your own cards before you order.
Card, tag and system compatibility
Works with
- ✓EM4100, TK4100 and SMC4001 125 kHz cards and key fobs
- ✓Windows or Linux hosts with an RS232 COM port
- ✓Background services and kiosk software that read a serial port
Card not listed? Send us the card type or a photo and we will confirm compatibility before you buy.
Integration in 4 steps
- 1
Connect the cable set to the reader and the DB9 connector to the host's RS232 port; provide 5 V DC as confirmed for your installation.
- 2
Open the COM port at 9600 bps in a serial terminal or in your service.
- 3
Place a card in the recess and check for one STX … ETX message containing the 10-digit card number.
- 4
Point your application at the port and test with the cards your users carry.
OEM / ODM options for L150-R
- ◆Baud rate preset (9600, 19200 or 115200 bps) on request
- ◆Custom card-number format within the serial frame on request
- ◆USB keyboard version in the same housing (L150-U)
- ◆13.56 MHz RS232 version (H150-R) for MIFARE sites
- ◆Private-label marking and packaging — scope confirmed in your quotation
Typical applications
L150-R FAQ
What comes in the L150-R cable set?
As pictured, a cable with a DB9 female serial connector and two USB-A plugs. We confirm the wiring and how the reader is powered for your host with your quotation.
Which baud rates does the L150-R support?
9600 bps by default, with 19200 and 115200 bps selectable. We can preset the rate before shipment.
Can a background service read the L150-R?
Yes. Unlike a keyboard reader, it does not need a focused text field: any program that opens the COM port receives each read.
Does the L150-R read MIFARE cards?
No, it reads 125 kHz EM4100-compatible cards and fobs only. The H150-R is the 13.56 MHz version of this housing.
Related readers
125kHz 13.56MHz H150-R
13.56MHz RS232 MIFARE Desktop Reader with Card Recess, DB9
- RS232
- Desktop
Read range: Up to 80 mm
125kHz 
125kHz Tell us your card, interface and quantity
Send the card or tag type, the host system and your volume. We reply within 1 business day with a suggested model and sample options.