Connecting And Setting Up The Micromaster Series 4 Drive - Siemens SIMATIC S7-200 System Manual

Connecting and Setting Up the MicroMaster Series 4 Drive

Connecting the MicroMaster 4 Drive
To make the connection to the MicroMaster Series 4 (MM4) drive, insert the ends of the RS-485
cable into the two caged clamp, screwless terminals provided for USS operation. The standard
PROFIBUS cable and connectors can be used to connect the S7-200.
Caution
Interconnecting equipment with different reference potentials can cause unwanted currents to
flow through the interconnecting cable.
These unwanted currents can cause communications errors or damage equipment.
Be sure all equipment that you are about to connect with a communications cable either shares
a common circuit reference or is isolated to prevent unwanted current flows.
The shield must be tied to chassis ground or pin 1 on the 9-pin connector. It is recommended
that you tie wiring terminal 2--0V on the MicroMaster drive to chassis ground.
As shown in Figure 11-6, the two wires at
the opposite end of the RS-485 cable
must be inserted into the MM4 drive
terminal blocks. To make the cable
connection on a MM4 drive, remove the
drive cover(s) to access the terminal
blocks. See the MM4 user manual for
details about how to remove the
covers(s) of your specific drive.
The terminal block connections are
labeled numerically. Using a PROFIBUS
connector on the S7-200 side, connect
the A terminal of the cable to the drive
terminal 15 (for an MM420) or terminal
30 (MM440). Connect the B terminal of 30 (MM440). Connect the B terminal of
the cable connector to terminal 14
(MM420) or terminal 29 (MM440).
If the S7-200 is a terminating node in the network, or if the connection is point-to-point, it is
necessary to use terminals A1 and B1 (not A2 and B2) of the connector since they allow the
termination settings to be set (for example, with DP connector type 6ES7 972--0BA40--0X40).
Caution
Make sure the drive covers are replaced properly before supplying power to the unit.
If the drive is configured as the terminating node in
the network, then termination and bias resistors
must also be wired to the appropriate terminal
connections. For example, Figure 11-7 shows an
example of the connections necessary for
termination and bias for the MM4 drive.
Using the USS Protocol Library to Control a MicroMaster Drive
Figure 11-6 Connecting to the MM420 Terminal Block
B (P)
MM420
P
14
120 ohm
N 15
470 ohm
0V 2
+10 V
1
MM440
P
29
120 ohm
N 30
470 ohm
2
0V
+10 V
1
Figure 11-7 Sample Termination and Bias
Chapter 11
A (N)
1.5K ohm
1.5K ohm
345