theben JM 8 T KNX 8-Way Blind Actuator (4940255)

Description

Introduction

The theben JM 8 T KNX (Item no.: 4940255) is an 8-way blind actuator from the FIX2 product series engineered for professional building automation applications. Operating within an AC voltage range of 110 V to 240 V AC at 50 Hz to 60 Hz, this actuator delivers direct control for motorized drives across blinds, shutters, sun and vision protection devices, skylights, and ventilation flaps. This device is part of our professional KNX Actuators range.

Designed for standard DIN rail mounting with an 8-module width, the device features built-in manual controls on the front panel. This allows installers and integrators to test and operate connected drives manually even without an active KNX bus connection. With a low standby power consumption of approximately 0.5 W, the actuator offers an energy-conscious control solution for modern KNX installations.

Key Features

• 8 independent output channels with NO (Normally Open) contacts rated at 6 A.
• Wide operating mains voltage range of 110 V AC to 240 V AC, 50 Hz to 60 Hz.
• KNX bus powered with low bus current consumption of ≤4 mA.
• Standard 8-module DIN rail enclosure for panel installation.
• Protection class II rating according to EN 60 669 with IP 20 ingress protection.
• Broad ambient operating temperature range from -5°C to 45°C.

Benefits

• 8-Channel Drive Control: Manages up to 8 independent motorized drives for blinds, shutters, skylights, or ventilation flaps from a single device.
• Bus-Independent Manual Override: Direct manual control buttons on the physical unit allow output testing and emergency operation without an active bus line.
• Low Standby Energy Overhead: Consumes approximately 0.5 W in standby mode, optimizing long-term energy utilization across the installation.
• Flexible Terminal Connections: Terminal screws support solid conductor cross sections up to 6 mm² and stranded wire with end sleeves up to 4 mm².
• SELV Output Compatibility: Supports potential-free switching contacts suitable for SELV applications provided the entire device is wired to switch SELV.

Technical Specifications

Specification	Value
Operating voltage KNX	Bus voltage, ≤4 mA
Operating voltage	110 V AC – 240 V AC, 50 Hz – 60 Hz
Frequency	50 – 60 Hz
Stand-by consumption	~0.5 W
Number of channels	8
Max. cable cross section	Solid wire: 0.5 mm² (Ø 0.8) to 6 mm² | Stranded wire with end sleeve: 0.5 mm² to 4 mm²
Output	NO contact, 6 A
Information Notice EU Data Act	PDF
Data sheet	PDF
Width	8
Installation type	DIN rail
Protection class	II according to EN 60 669
Type of connection	Terminal screws | Bus connection: KNX bus terminal
Switching output	Potential-free, for SELV, if the whole device switches SELV
Ambient temperature	-5°C … 45°C
Operating instructions	PDF
Type of protection	IP 20
Hand book	ZIP
KNX-Database (Single Product)	ZIP
CAD symbol	ZIP

Applications

• Automated shading control for motorized window blinds, shutters, and vision protection screens.
• Motorized opening and closing control for skylights and roof windows.
• Automated control of ventilation flaps in HVAC and facade management systems.

Installation Notes

• Mount the 8-module unit onto a standard DIN rail inside an IP 20 environment or electrical distribution box.
• Connect solid conductors (0.5 mm² to 6 mm²) or stranded conductors with sleeves (0.5 mm² to 4 mm²) using the terminal screws.
• Connect the KNX bus line to the standard KNX bus terminal, verifying bus current draw remains within the ≤4 mA limit.
• Ensure the operating mains supply is within 110 V – 240 V AC at 50 – 60 Hz prior to powering the unit.

Developer Resources

• KNX ETS Database (Single Product) ZIP download for system integration.
• Technical Data Sheet PDF and EU Data Act Information Notice PDF.
• Comprehensive product Handbook ZIP file and Operating Instructions PDF.
• CAD Symbol ZIP file for system schematics and panel layout design.

FAQ

Can the theben JM 8 T KNX be operated manually without a KNX bus connection?

Yes, manual operation controls are available directly on the device, allowing physical control of the outputs even if the bus connection is absent or disconnected. Explore more theben building automation products for professional building automation projects.

What is the output relay rating for each channel?

Each of the 8 channels features a Normally Open (NO) contact rated at 6 A. For certificates and current technical files, refer to the official product documentation.

What wire gauges can be connected to the terminals?

The screw terminals support solid conductors from 0.5 mm² (Ø 0.8) to 6 mm² and stranded wire with end sleeves from 0.5 mm² to 4 mm².

What is the standby power draw of this actuator?

The device consumes approximately 0.5 W in standby mode.

What is the exact product model?

The order/model code for this page is 4940255. Match it against project documents before purchase.

Who is the manufacturer?

This product is manufactured by theben.

Conclusion

The theben JM 8 T KNX (4940255) provides a robust, 8-channel blind and shading control solution in a standard 8-module DIN rail footprint. Featuring manual override capabilities independent of the bus, broad voltage support, and low standby energy draw, it is an efficient component for modern KNX automation projects. Installers and system integrators can review our professional project support options.