Lenze MCH Series Drives Siemens P1 - Manual (Page 6)

3 RG-MHSP1F
Introduction
2 Introduction
This document will explain how to connect a Lenze-AC Tech MCH Variable Frequency Drive to a Siemens
P1 Floor Level Network (FLN). It is intended as a serial communications supplement only and will not
discuss normal drive operations. For more information regarding normal drive setup and functionality, refer
to the MCH Installation and Operation Manual (MH01).
2.1 Floor Level Network Communications
The Floor Level Network LAN is used to establish Direct Digital Control (DDC). A Field Cabinet directs all
activity on the FLN. The name Field Cabinet is a generic name for several products, including the Modular
Building Controller (MBC), Stand-alone Control Unit (SCU), LAN controller and the Apogee MBC.
The Field Cabinet maintains a Master & Slave relationship with the individual FLN devices. This means that
all communication on the FLN is initiated by the Field Cabinet (the Master) and a FLN device (a Slave) only
responds when it is issued a command.
The FLN utilizes the P1 Protocol, which is an asynchronous communication protocol. Communication is half
duplex, 8 data bits, no parity, 1 stop bit -- All data is transmitted LSB first. Handshaking is not implemented
for P1. The bit sequence is as follows:
DATA
START 1 2 3 4 5 6 7 8 STOP
CRC-16 Error Detection (transmitted MSB first) is used to ensure that messages are received correctly.
In the United States, Siemens currently uses two controller operating systems for Building Automation
Systems that use P1 for communication. One is Apogee. The other is System 600, also referred to as Pre-
Apogee. Lenze-AC Tech MCH Series P1 Drives have been tested and are compatible with both systems.
2.2 Hardware Description
The FLN Local Area Network port utilizes RS-485 compliant hardware. The FLN device is one of up to 32
nodes on the LAN. The communications rate is typically 4800 bps. However, on certain FLN devices, it may
also be 9600 bps.
2.3 Serial Communications Wiring
Figure 1 illustrates the MCH Series Terminal Strip and connections for a Siemens P1 FLN.
2 1 5A 5B 6 10A 10B 2 13A 12A 13B 13C 13D 14 15 2 TXB RXA 16 17 18
FLN -
FLN +
Earth
Ground
Figure 1: MCH Terminal Strip
Connect the FLN+ terminal to MCH terminal TXB. Connect the FLN- terminal to MCH terminal RXA.
Connect MCH terminal 2 to Earth Ground. Do NOT connect the FLN S (Shield) wire to the drive.