Basic Documentation

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Siemens RWD Primary Controls Modbus Interface CB1P3099en_01

Building Technologies RWD Parameters & Addresses 27.10.2009

• The SEZ50MB only support Modbus commands for either READ or WRITE of one

parameter each time. If access to consecutive parameters is required, users should

issue multiple commands manually or via any Modbus SW tool;

• Each command string may vary depending on function code used, some function

codes may take longer time to be processed by SEZ50MB. The longest process time

of SEZ50MB would be around 6 seconds;

• Some values may be rounded by SEZ50MB before passing to RWD in order to fulfill

the current STEP SIZE and RESOLUTION. For example, if a setpoint is entered as

16.7, it will be presented as 16.7 or rounded to 16.5 – depends on its resolution

settings;

• The parameter with

is not recommended to be used during the normal operation of

RWD, but can be used during maintenance.

E.g. Write specific value to parameter address “40179” with function code “0x10” and

it will cause reset.

Therefore, special attention is required:

Write 12 (0x0C) to device address “40179” to reset RWD32/62/68/82

Write 167 (0xA7) to device address “40179” to reset RWD34/44/45

5 RWD Parameters & Addresses

The following parameter table contains all available RWD parameters including all input

and output signal status. These parameters are mainly for monitoring functions via

Modbus network and some of them can be modified during operation.

Besides function codes (READ or WRITE) provided in section 4, you also can refer to

the following parameter table for the interpretation of the correct responds or returned

values. For more details about RWD parameters, please check individual RWD

datasheet.

• Please refer to SEZ50MB Parameter Tool for valid parameters of different RWD

models;

• Avoid frequent daily WRITE actions to RWD via Modbus because there are limited

write cycles allowed for the memory and storage devices where all RWD SW

parameters stored;

• The * next to the parameter addresses indicate that this parameter can execute both

READ and WRITE function codes;

• The

means this parameter should not be used for normal operation;

• If error occurs during the operation or error message received, please refer to the

section "Trouble Shooting" for more information.

Notes: