Arkel KM-20 DC Door Control Board: Intelligent Control for 24V Telescopic Doors

The Arkel KM-20 is a sophisticated door control unit specifically designed for 24V DC geared motors used in telescopic automatic elevator doors. It replaces traditional limit switch systems with high-precision position detection via motor encoders, ensuring smooth, safe, and synchronized door operation.

Technical Specifications: KM-20 DC

Product Description

The Arkel KM-20 DC represents a significant upgrade over standard door controllers by utilizing smart technology to manage 24V DC telescopic doors. Unlike older systems that rely on mechanical limit switches—which are prone to wear and misalignment—the KM-20 uses a dual-channel encoder input to track the exact position of the door wings. This allows for precise “S-curve” acceleration and deceleration, ensuring smooth and silent operation without banging against door stops.

Safety and Emergency Features: Safety is paramount in the KM-20’s design. It actively monitors motor current to detect obstructions. If a passenger or object blocks the door, the system detects the “squeeze” pressure and immediately reverses the door to the open position. Furthermore, in the event of a mains power failure, the unit seamlessly switches to its connected battery backup (2x 12V) to move the car door to the open position, allowing passenger evacuation.

Versatile Application: The KM-20 is highly adaptable. It provides relay outputs for “Fully Open,” “Fully Closed,” and “Obstruction/Photocell” states, allowing seamless integration with any main lift controller. For specialized applications, it supports Nudging Mode (forced closing with alarm) and is compatible with Fire Lift requirements where high-speed signal detection is necessary.

Frequently Asked Questions (FAQs)

Q1: Does the Arkel KM-20 require mechanical limit switches to function?

No. The KM-20 utilizes encoder feedback from the motor. It automatically learns the door width and detects open/closed positions digitally, eliminating the need for mechanical limit switches and reducing maintenance needs.

Q2: How does the KM-20 handle power outages?

The board has a built-in battery charging circuit. It supports 2 units of 12V batteries (or an external 24V DC supply). If mains power is lost, the card automatically switches to battery power to drive the door open, preventing passenger entrapment.

Q3: Can I adjust the door speed and closing force?

Yes. Basic parameters like opening/closing speed and obstruction pressure can be adjusted directly using the onboard buttons and digital display. For more advanced setup and monitoring, an optional external KM-20 Keypad can be connected.

Q4: What is “Nudging Mode” and does KM-20 support it?

Yes, the KM-20 supports Nudging Mode. If the photocell beam is broken for a long time (holding the door open), the system can ignore the photocell and close the door slowly while sounding a buzzer to discourage holding the elevator, improving traffic flow.