Perceived complexity |
Engineering Cost & Efforts |
Operation efficiency & transparency |
2nd channel access ( Monitoring + Optimization ) |
MRO Functionality / Performance |
|
Ethernet-APL |
One single network technology |
Reduced engineering time per device
Flexible topology and redundancy
|
Seamless data access
Fully digital data transfer
|
Easy and fast access
Multiple communication channels
|
Remote diagnostic and configuration access
Fast device exchange
|
Fieldbus |
Requires gateways and protocol conversion |
Limited total cable length and participants of each bus segment |
Data access with protocol conversion
Fully digital data transfer
|
Additional hardware
Low bandwidth
One message at a time ( half duplex )
|
Remote diagnostic and configuration access
Challenging fieldbus troubleshooting
|
4-20mA , optional HART |
Current signal easy to understand |
Extensive hazardous area calculation |
AD / DA conversion leads to loss of accuracy
Limited data access
|
Additional hardware
Very low bandwidth
One message at a time ( half duplex )
|
Low diagnostic information
Troubleshooting at device
HART : Slow
|