CoriolisMaster FCB400, FCH400
CORIOLIS MASS FLOWMETER | OI/FCB400/FCH400-EN REV. E
63
Limits and rules when using ABB fieldbus accessories
Figure 53: Bus cable length depends on the transmission rate
Pro PROFIBUS Line
(Line = Starts at DP Master and goes to last DP/PA Slave)
• Approximately 4 to 8 DP segments through the repeater (see
repeater data sheets)
• Recommended DP transfer rate 500 to 1500 kBit/s
• The slowest DP node determines the transfer rate of the DP
line
• Number of PROFIBUS DP and PA nodes
≤
126 (addresses
0 to 125)
Per PROFIBUS DP segment
• Number of DP nodes
≤
32
(Node = Devices with / without PROFIBUS address)
• Bus termination required at the beginning and end of each
DP segment!
• Trunk cable length (L
T
) see diagram (length dependent on
transfer rate)
• Cable length of at least 1 m between two DP nodes at
≥
1500 kBit/s!
• Spur cable length (L
S
), at
≤
1500 kBit/s: LS
≤
0.25 m,
at > 1500 kBit/s: LS = 0.00 m!
• At 1500 kBit/s and ABB DP cable type A:
– Sum of all spur cable lengths (L
S
)
≤
6.60 m, trunk cable
length (L
T
) > 6.60 m, total length = L
T
+ (
Σ
L
S
)
≤
200 m,
maximum 22 DP nodes (= 6.60 m / (0.25 m + 0.05 m
spare))
