The KL4021 is a high-precision, 1-channel analog output terminal designed for the Beckhoff Bus Terminal system. It generates standard industry signals ranging from 0 to 20 mA, utilizing single-ended output technology. With a 12-bit resolution and a fast conversion time of approximately 1.5 ms, this terminal is ideal for controlling analog actuators or process instrumentation in industrial automation environments. The module provides robust electrical isolation between the K-bus and field signals, ensuring reliable data transmission.
Features
1-channel analog output (0…20 mA)
Single-ended technology
12-bit resolution for precise signal control
Fast conversion time (~ 1.5 ms)
Robust electrical isolation (500 V)
Certified for hazardous areas (ATEX/IECEx)
Technical Specifications
Feature
Specification
Manufacturer
Beckhoff
Number of Outputs
1
Output Signal
0…20 mA
Load
< 500 Ω
Resolution
12 bit
Conversion Time
~ 1.5 ms
Electrical Isolation
500 V (K-bus/signal)
Protection Rating
IP20
Weight
Approx. 80 g
Approvals
CE, UL, ATEX, IECEx, DNV GL
Installation Guidelines
Mounting: Secure the KL4021 onto a standard 35 mm DIN rail (EN 60715). Ensure the locking mechanism is engaged for proper power contact with the terminal bus.
Power Supply: Operates on 24 V DC via power contacts. If 15 V DC operation is required for specific application needs, a KL9515 power supply terminal must be used.
Wiring: Use shielded twisted-pair cables for analog signal connections to minimize electromagnetic interference (EMI). Ground the shield correctly at the signal source or load to maintain signal integrity.
Safety: In hazardous environments (ATEX/IECEx Zone 2), ensure the terminal is housed in an enclosure that meets the requirements for the specific area classification.
Environment: Maintain operating temperatures between 0 degC and +55 degC and keep relative humidity below 95% (non-condensing).
FAQ
What is the output signal range for the KL4021?
The terminal outputs a standard 0 to 20 mA signal.
What is the resolution of the analog output?
The KL4021 provides a resolution of 12 bits.
Is this terminal suitable for hazardous locations?
Yes, it carries ATEX and IECEx certifications for use in specific hazardous environments.
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