Order now the 20-COMM-H, a specialized HART communication adapter designed for integrating PowerFlex 700S drives into process instrumentation networks.
What Is the 20-COMM-H?
The 20-COMM-H is a unique communication adapter that enables the Highway Addressable Remote Transducer (HART) protocol on Allen-Bradley PowerFlex 7-Class drives, particularly the PowerFlex 700S with Phase II control. This module allows the drive to act as a bridge between the industrial control system and HART-compatible field devices. It is widely used in the process industries (oil, gas, and chemical) where HART is the standard for transmitting digital diagnostics over 4-20mA analog loops. The 20-COMM-H enables the drive to pass through HART commands, allowing maintenance software like FactoryTalk AssetCentre to calibrate and monitor instruments directly through the drive’s communication infrastructure, streamlining asset management and predictive maintenance.
Key Technical Specifications
- Network Protocol: HART (Highway Addressable Remote Transducer)
- Interface: Internal DPI (Drive Peripheral Interface)
- Compatibility: PowerFlex 700S Phase II Control
- HART Channels: Supports multiple virtual channels for instrument data
- Configuration: Via HIM or DriveExplorer software
- Diagnostics: Real-time device health and status pass-through
Process Control and Asset Management
The 20-COMM-H architecture is specifically designed for complex process control environments. It leverages the digital-over-analog capabilities of HART to provide a wealth of diagnostic information that traditional 4-20mA signals cannot. For instance, a drive equipped with a 20-COMM-H can report sensor calibration dates, device serial numbers, and specific error codes from the field instrument directly to the control room. This capability is vital for complying with safety and regulatory standards in process plants, as it ensures that the «health» of the entire control loop—from the drive output to the final sensor—is constantly verified.
Expert Tips
When using the 20-COMM-H, ensure that the analog wiring is of high quality and that the loop impedance is within the HART specification (typically 230 to 600 ohms) to ensure reliable FSK (Frequency Shift Keying) signal transmission. If communication is intermittent, check for high-frequency noise on the analog lines; the use of dedicated HART filters may be necessary if the drive’s PWM output is interfering with the low-level HART digital signal. Always verify that the field device’s HART revision is compatible with the 20-COMM-H firmware to ensure full parameter access.
Frequently Asked Questions
Q: Is the 20-COMM-H compatible with the PowerFlex 750 series?
A: No, the 750 series uses the 20-750-HART module. The 20-COMM-H is specific to the older 7-Class DPI architecture, primarily the 700S.
Q: Can I use a HART handheld terminal while the 20-COMM-H is active?
A: Yes, HART is a master/slave protocol that supports up to two masters (a primary and a secondary), so a handheld terminal can be connected to the loop simultaneously.
Do you need more references from this brand? Explore our full catalog of Allen-Bradley here: https://atlantechdrives.com/manufacturers/allen-bradley/
