Serial Interfaces With Peer-To-Peer Protocol - Siemens SIMOTRAS 6SG7050 Operating Instructions Manual

Function descriptions
Connection example for a USS bus
Master
(Bus terminating
resistors activated)
SIMATIC S5
CP524 with RS485
module ...0AA43
(Bridge X3: 20-18 -->
2-wire cable)
Rx
14 12 10
X3
-
4
SUB-D connector
15-pole
1)The interface cable shields should be connected at low impedance directly to the converters on the converter or
cabinet ground (e.g. using a clamp).
2) Twisted-pair cable, e.g. LIYCY 2x0.5 qmm; in the case of longer cable runs, an equipotential bonding conductor should
be used to ensure that the difference of the frame potentials between the connected units remains below 7V.
9.9.2

Serial interfaces with peer-to-peer protocol

The term "Peer-to-peer link" refers to a "Link between partners of equal status". In contrast to the
classic master/slave bus system (e.g. USS and PROFIBUS), the same converter can function as both
the master (setpoint source) and the slave (setpoint receiver) in a peer-to-peer link.
Signals can be transferred in fully digital form from one converter to another via the peer-to-peer link,
for example:
− Velocity setpoints
− Torque setpoints
− Acceleration setpoints (dv/dt)
− Control commands
Useful data which can be transferred via the peer-to-peer link
Sheets G172 and G174 show how useful data can be interconnected and list the parameters relevant
for configuring peer-to-peer links. Any connectors can be parameterized as transmit data (numeric
representation: 100% equals 4000h = 16384d).
Parameters cannot be transferred via the peer-to-peer link.
Transfer of double-word connectors:
In the receive direction, the values of any two adjacent connectors (K) are combined to form a double-
word connector (KK) (e.g. K6001 and K6002 to KK6081). These double-word connectors can be
connected in the usual way to other function blocks. For details of how to connect with double-word
connectors, see Section 9.1, subsection "The following rules apply to the selection of double-word
connectors".
In the transmission direction, a double-word connector is applied by entering the same double-word
connector at two contiguous indices of the selection parameter.
9-24
Slave 1
(Bus terminating
resistors deactivated)
6SG70
Rx
Tx
8 6 4
X3
-
+
59
11
150 Ω
2)
1)
Slave 2
(Bus terminating
resistors deactivated)
6SG70
Tx Rx
+
+ -
58 59
resistors activated)
Tx
+
+
58
SIEMENS AG
SIMOTRAS HD Operating Instructions
01.04
Slave n (n<=31))
(Bus terminating
6SG70
Rx Tx
+
- +
59 58
6SG7000-0BA76