Over 15 years experience of providing support of MEAN WELL Power Supplies
Mean Well KNX-40E-1280D KNX Power Supply 1280mA - Diagnostic 1280A
Notify me when it's back in stock
Your order will be processed within 24 hours
Overview
KNX-40E-1280D is the model of this series: rated current 1280mA, rated power 38.4W, typical efficiency 86%.
MEAN WELL, the leading standard power supply manufacturer, continues to promote the building automation technology for making a green and sustainable society. After the launch of KNX-20E-640, the new KNX power supply KNX-40E-1280(D) is proudly introduced. The KNX Power Supply KNX-40E-1280(D) is a 1280mA power supply with high efficiency and a small footprint of only 4SU(72mm). The device has a KNX bus choke output and additional output for auxiliary power. The -30~+70°C wide temperature operating range can meet all kinds of applications. For troubleshooting, monitoring purpose, output voltage, output current, bus traffic, device temperature and other actual measurement values can be sent via KNX. LED indicators are used in case of normal operation, overload conditions and RESET operation. It is perfectly suitable to power up any products labeled with the KNX trademark.
Features
- EIB / KNX power supply with integrated choke
- Compact size with 4SU width(72mm)
- Safety extra low voltage(SELV)
- Suitable for TP1-256
- 180~264VAC input
- Protections: Short circuit / Overload(short-circuit-proof)/ Over voltage
- Cooling by free air convection
- Isolation classⅠ
- LED indicator for normal operation, bus reset and bus overload
- Monitoring of output voltage, output current, bus traffic load and device temperature
- Provide Wide variety of diagnostic and logic function
- Over Voltage category Ⅲ
- 3 years warranty
Specifications
OUTPUT
- BUS OUTPUT VOLTAGE WITH CHOKE
- Bus,30V (KNX black/red terminal block)
- DC OUTPUT VOLTAGE WITHOUT CHOKE
- 30V(Additional output for ancillary power)
- RATED CURRENT
- 1280mA
- RATED POWER
- 38.4W
- RIPPLE & NOISE (max.)Note.2
- 100mVp-p
- SHORT CIRCUIT CURRENT
- 2.8A
- SETUP, RISE TIME
- 1000ms, 50ms/230VAC at full load
- AC MAINS FAILURE BACK-UP TIME (Typ.)
- 200ms/230VAC at full load
INPUT
- VOLTAGE RANGE
- 180 ~ 264VAC 176 ~ 280VDC
- FREQUENCY RANGE
- 47 ~ 63Hz
- EFFICIENCY (Typ.)Note.3
- 86%
- AC CURRENT (Typ.)
- 0.5A/230VAC
- INRUSH CURRENT (Typ.)
- COLD START 60A(twidth=1200μs measured at 50% Ipeak)/230VAC
- LEAKAGE CURRENT
- <1mA / 240VAC
PROTECTION
- OVERLOAD
- 205 ~ 235% rated output power Protection type : Constant current limiting, recovers automatically after fault condition is removed
- OVER VOLTAGE
- 33 ~ 35V Protection type : Hiccup mode, recovers automatically after fault condition is removed
FUNCTION
- RESET
- Physical button for the bus reset: Blank type:Press the RESET button for at least 20 seconds to reset the KNX Bus D type:Press the RESET button once,it will reset the KNX Bus last for 20 seconds automatically
- LED INDICATORS
- Please refer to the “Explanation of LED Status”
- CHOKE
- One integrated choke
ENVIRONMENT
- WORKING TEMP.
- -30 ~ +70°C (Refer to "Derating Curve")
- WORKING HUMIDITY
- 20 ~ 95% RH non-condensing
- STORAGE TEMP., HUMIDITY
- -40 ~ +85°C, 10 ~ 95% RH non-condensing
- VIBRATION
- 10 ~ 500Hz, 2G 10min./1cycle, 60min. each along X, Y, Z axes
- TYPE OF PROTECTION
- IP20 design
- OVER VOLTAGE CATEGORY
- Ⅲ ,According to BS EN/EN61558, BS EN/EN50178,altitude up to 2000 meters
SAFETY & EMC (Note 4)
- SAFETY STANDARDS
- BS EN/EN61558-1,BS EN/EN61558-2-16;BS EN/EN50491-3 approved
- WITHSTAND VOLTAGE
- I/P-O/P:4.2KVAC I/P-FG:2KVAC
- ISOLATION RESISTANCE
- I/P-O/P, I/P-FG:100M Ohms / 500VDC / 25°C/ 70% RH
- EMC EMISSION
- Compliance to BS EN/EN50491-5-2,-5-3;BS EN/EN61000-3-2,-3-3
- EMC IMMUNITY
- Compliance to BS EN/EN50491-5-2,-5-3;BS EN/EN61000-4-2,3,4,5,6,8,11, heavy industry level
OTHERS
- MTBF
- 1414.2K hrs min. Telcordia SR-332 (Bellcore) 217.1Khrs min. MIL-HDBK-217F (25°C)
- DIMENSION
- 72*90*57mm (W*H*D)
- MOUNTING
- 35mm mounting rail according to DIN BS EN/EN60715
- PACKING
- 0.328Kg ; 48pcs/16.4Kg/1.02CUFT
Test conditions and notes5
- 1. All parameters NOT specially mentioned are measured at 230VAC input, rated load and 25°C of ambient temperature.
- 2. Ripple & noise are measured at 20MHz of bandwidth by using a 12" twisted pair-wire terminated with a 0.1uf & 47uf parallel capacitor. Measure before Choke.
- 3. Efficiency before choke.
- 4. The power supply is considered a component which will be installed into a final equipment. The final equipment must be re-confirmed that it still meets EMC directives. For guidance on how to perform these EMC tests, please refer to “EMI testing of component power supplies.” (as available on https://www.meanwell.com//Upload/PDF/EMI_statement_en.pdf)
- 5. The ambient temperature derating of 3.5°C/1000m with fanless models and of 5°C/1000m with fan models for operating altitude higher than 2000m(6500ft).
Technical drawings
Typical applications
- Intelligent home control
- Modern building automation
- Lighting control
- HVAC system
- Security system
- Blinds and shutters
- Monitoring systems
- Energy management
- Alarm monitoring
Downloads
Certificates6
Test reports1
FAQ
Can the KNX-40E-1280D be used for a higher-capacity KNX control cabinet in building management?
Yes. This model is rated at 30V, 38.4W, and 1280mA, so it suits KNX building management cabinets that need a 1280mA bus supply. It is also designed as a DIN rail power supply for panel use.
Is the KNX-40E-1280D suitable for centralized KNX automation panels in commercial control enclosures?
It is well suited to centralized KNX control enclosures that use a 30V KNX supply and need the 38.4W, 1280mA rating. The integrated choke lets it feed the KNX bus directly. Its 72 × 90 × 57 mm (W × H × D) size mounts on a standard 35mm DIN rail in cabinet layouts.
Can I use the KNX-40E-1280D in a PLC cabinet that also includes KNX-based building control functions?
Yes, when the KNX portion of the cabinet needs a dedicated 30V KNX power supply within a 38.4W and 1280mA rating. The DIN rail format makes it practical for mixed-control cabinets where panel organization matters. It should still be selected as a KNX power component, not as a general-purpose cabinet supply.
Should the KNX-40E-1280D be installed only inside an enclosure or cabinet?
It is best used inside a control cabinet or enclosure. The operating temperature range is -30°C to +70°C (refer to the derating curve), and the unit has an IP20 design. That makes protected indoor cabinet use the appropriate environment.
How does the KNX-40E-1280D compare with the other models in the KNX series?
The KNX-40E-1280D is a 38.4W, 30V, 1280mA model. The KNX-40E-1280 in the same series has the same 38.4W, 30V, 1280mA rating. The D version adds a fuller diagnostic LED set and a KNX communication object table, and its RESET button resets the bus with a single press instead of a 20-second hold.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Other KNX-40E Models
1 other model| Model | Power | Voltage | Current | IP Rating | Price | |
|---|---|---|---|---|---|---|
| Mean Well KNX-40E-1280 KNX Power Supply 1280mA 1280A | 38.4W | 30V | 1.28A | IP20 | $128.67 | View |
Please log in to write a review.
Write a review
Reviews are checked before publishing. By submitting you confirm this is your genuine experience with this product.
Submitting your review…
It's published and now helps other buyers.
We're checking it and it'll appear shortly.
Please try again.





