K8EM-W Vandal-Resistant Metal Housing Card Reader and Code Lock

The K8EM-W is a vandal-resistant, standalone card reader and code lock with a metal housing that supports 125 kHz EM cards and PIN codes. As a standalone access control device, it features lock control via a relay with a dry contact. Through its Wiegand input, it can manage an auxiliary reader (configurable Wiegand format) and can also function as an auxiliary reader itself when switched to the appropriate mode. Besides the adjustable Wiegand format, the LED and buzzer feedback can be freely toggled on and off.

This device is an alternate model of the highly popular SK-8EM-W(V1). It matches the SK-8 in appearance and most functionalities. Key differences compared to the SK-8EM-W(V1) include:

    • no Anti-Passback feature,

    • no multi-card opening,

    • no tamper switch,

    • non-disabling keypad backlight,

    • does not support door sensor and alarm,

    • includes a data copying function (transfers users to another device).

Standalone Card Readers

Standalone readers are access control devices capable of reading cards or other forms of identification and managing lock control without needing a separate reader or controller. Lock control usually occurs via a relay with a dry contact, although some devices can switch between dry and wet contacts.

Relay Construction

The relay typically has three pins: normally open, normally closed, and common. In its default state, the common and normally closed pins are shorted. When the relay activates (i.e., the access control grants entry), the short moves to the common and normally open pins for the duration of the access.

Dry vs. Wet Contacts

    • Dry Contact: The relay provides the circuit but not the voltage; an external power source is required. The wiring must ensure the circuit is completed, considering the relay's load capacity.

    • Wet Contact: The device itself supplies the voltage to the lock, simplifying wiring as the lock doesn't need a separate power supply connection, only to the relay's appropriate pins.

Additional Peripherals

Beyond the lock, standalone readers can connect to other peripherals like a door release button, auxiliary reader, door sensor, bell, or alarm. These peripherals can enhance functionality but are optional.

Tamper Switch

Many standalone readers feature a tamper switch, either mechanical or optical, to trigger an alarm if the device is removed from the wall, preventing unauthorized access by tampering with the wiring.

Conclusion

Standalone readers are ideal for simple and efficient access control implementations, offering flexibility and ease of installation while ensuring necessary security features. The ability to integrate various peripherals allows the system to adapt to user needs, making standalone readers a practical and reliable solution for numerous access control challenges.