The FTC470XDP protocol converter
17
FTC470XDP_D00111_00_M_XXEN/02.2015
4.4.3
FTC470XDP communicates with the PROFIBUS DP Master as ’BMS Slave’
If a BMS address between 2 and 30 has been assigned to the FTC470XDP, it acts as a BMS Slave. In
this case, the PROFIBUS DP Master can use the following functions:
* For detailed information about the PROFIBUS instruction code refer to the tables "Function lists" on
page 27.
Temporary taking over of the Master function
Setting or requesting parameters of BMS cannot be carried out unless the FTC470XDP has taken over
the Master function on the BMS bus. After the setting respectively the requesting of parameters, the
Master function must be returned to the initial BMS Master. The associated commands can be found
on page 36.
If no parameters are transmitted to the BMS bus by the PROFIBUS DP for 200 seconds, the
FTC470XDP "assumes" that the Master function has not been returned. In this case, the FTC470XDP
automatically returns the Master function to the initial BMS Master in order to avoid that the BMS bus
is operated without a Master and hence would not be able to function reliably.
The response time for taking over or returning the Master function depends on the extension of the
BMS system. A typical response time is approximately 6 seconds, but may be up to 60 seconds in ex-
tended systems.
The time needed to execute the instruction codes 1, 2, 3, 4, 105, 102 and 104 is about 20 ms.
If FTC470XDP is operating to the internal interface of TM operator panel or PRC1470, a Master take
over cannot take place. In this cause only the functions described on page 17 can be used.
Function in the BMS network
PROFIBUS
DP
instruction
code*
Request for the number of alarm messages of a device
1
Request for the alarm message of a channel
2
Request for the number of operating messages of a device
3
Request for the operating message of a channel
4
Request for the current measuring value of a channel
105
Transmission of an alarm message from the PROFIBUS to a chan-
nel of the FTC470XDP
102
Transmission of an operating message from the PROFIBUS to a
channel of the FTC470XDP
104
Starting, stopping or setting the position mode at EDS470/473
systems
115
Taking over respectively returning the Master function
112
Please note that some BMS Masters cannot return their Master function
