Surefire BMS-350, Инструкция по установке и эксплуатации

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MODBUS INFORMATION
Programming Information for
Surefire BMS-350 with Modbus Interface
(Firmware Name: Modbus 350)
6 May 2019
This document describes the programming interface for the BMS-350 burner controller using the Modbus
interface board. The Modbus registers, their contents, command sequencing and examples of command exe-
cution over Modbus are described.
This document applies to firmware revisions 1.9. In order to use Modbus 1.9, the BMS-350 must be upgraded
to firmware package 2.6.
1.0 Introduction
The Modbus interface to the BMS-350 is accomplished via an intermediary processor board, the BMS Mod-
bus board. The function of this board is to serve as a Modbus RTU slave , handling requests from the
Modbus master to read information and relay command data to the BMS-350 board.
The Modbus board behaves as a specialized “mailbox”; a set of Modbus holding registers is available in the
Modbus board, any of which can be read or written by either the BMS board or the Modbus master. This ar-
rangement relieves the BMS board of the job of hosting the Modbus and relaxes many of the timing con-
straints that would overtax the limited hardware resources on the BMS board MCU.
A number of the registers are constantly updated by the BMS board with information such as temperatures,
modes, output states, ignition attempts, and other important data. These should be treated as read-only by the
Modbus master. Other registers are defined as command and parameter registers to be written by the Modbus
master to cause the BMS board to perform an action or set an operational variable (such as high temperature
limit).
Both RS-485 and RS-232 interfaces are available for use by the Modbus master. Only one of these interfaces
can be selected for use at any given time via the configuration DIP switch. The configuration DIP switch also
sets the Modbus address and the baud rate.
LEDs are present on the Modbus board to indicate processing of Modbus packets (from the Modbus side) and
BMS-350 packets (from the BMS-350 side). The LEDs illuminate when intact packets are received and
are being processed . Under normal operation the LED on the BMS side should show regular activity as it
updates the holding registers on the Modbus board and queries for command data. The LED on the Modbus
side will only show activity if the Modbus master is reading from or writing to the Modbus board.
2.0 Amber LED Indication
There are two LEDs in the Modbus circuit board that indicates different operations
COM LED:
This LED indicates that the Modbus circuit board is communicating and sending data packages to the BMS-
350 circuit board. This LED is located between the MCU chip and the large terminal block and is ;labeled
COM.
BMS COM LED:
This LED indicates that the BMS-350 is communicating and sending data packages to the Modbus circuit
board. This LED is located between the MCU chip and the small terminal block and is labeled BMS COM.