Dressler 13150 400 V, User Manual

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HPG 13150 400 V (A) Communication Interfaces 4-31
HPG™ 13150 400 V RF Power Generator
Prerelease version
PROFIBUS Master Reset Command
Send the master reset command, Command 119 , when the HPG generator
supply has experienced a non-recoverable (“explicit clear”) fault (that is, a
configuration fault or a PROFIBUS error fault). Dressler recommends sending
this command upon the startup of PROFIBUS communications so that any
existing fault indications will be cleared.
PROFIBUS-Specific Errors
In the event of a PROFIBUS error, the HPG generator turns off output power
and sets the PROFIBUS fault status bit. All PROFIBUS errors are treated as
“explicit clear” type faults; thus, you must send
Command 119 (the “master
reset” command) in the next download packet to clear them. Once all faults
have been cleared, the HPG generator is ready to continue operation.
PROFIBUS Data Consistency
Some Programmable Logic Controllers (PLCs) using PROFIBUS interfaces
have a problem with
data consistency . (Dressler defines data consistency as
the ability to complete the message packet construction before sending the
packet to the HPG generator.) This problem most often manifests as
mysteriously changed values. That is, values at the HPG generator seem to
have changed automatically even though no command has executed, or the
values appear changed because one data bye contained the data that another
data byte should have contained.
The root of the problem is a shared memory block. Most PLCs share a
memory block with the
PROFIBUS interface. The PLC places data/packet
information in the memory block, and the PROFIBUS interface reads the
memory block for the next data/packet to transmit. The problem occurs when
the PLC updates the data from High to Low memory locations and does not
signal the
PROFIBUS interface when the update is complete. (If the PLC were
to notify the PROFIBUS interface, then there would be “data consistency.”) As
a result, the PROFIBUS interface sends the memory block regardless of
where the PLC is in its update of that memory block.
Red (steady) Off The PROFIBUS system is off
or unavailable.
Red (flashing) Error The PROFIBUS system is
currently in a stop or clear
condition, exchanging data,
or in an error recovery
sequence. See
“PROFIBUS-
Specific Errors” on page 4-31
Table 4-5. PROFIBUS status LEDs (Continued)
LED Indication Unit Status