Online Electronics 4003 MAGSIG, Руководство по эксплуатации

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4003_5001_D02 Page 17 of 35
4.5.25. EXIT MENU
Selecting this item will EXIT the menu interface and the unit will resume LISTENING.
4.6. MODBUS RTU RS485 INTERFACE
Communication to the 4003, via the RS485 interface, makes use of MODBUS protocol as defined
in MODBUS OVER SERIAL LINE V1.02 published by the MODBUS organisation. The
communication parameters adhere to this standard using the default RTU transmission mode.
Communication parameters can be set up via the Menu System, Bluetooth application or
MODBUS itself. All the parameters in the 4003 can be accessed via the MODBUS interface.
MODBUS is also used over Bluetooth via a VCP connection which requires additional software.
The 4003 implements an exclusive block structure where each type of block has its own unique
addresses. The base address for each type will remain constant although the content and number
of each type of registers maybe updated but a table will exist in the manual detailing the register
map applicable to the version of software for the 4003.
TYPE START
ADDRESS
FUNCTION CODES
COILS 10000 1,5
HOLDING REGISTERS 40000 3,6,16
INPUT REGISTERS 30000 4
The 4003 contains two processing units. The Main Processor performs the majority of the
operational functions of the unit. The Communications Processor handles current loop signalling
and MODBUS communications. The two units are electrically isolated from each other so that
the communication interface can be isolated from the housing earth connection. The electrical
ground connection for the Main Processor is connected to the housing earth due to the use of
Zener Barrier type circuits inside the 4003 as required by hazardous area certification.
When MODBUS registers are updated the new values need to be transferred from the
Communications Processor to the Main Processor so there is a slight delay to enable this to be
performed. The Communications Processor keeps a copy of all registers which are updated by
the Main Processor. Again, there may be a slight delay in this update.
4.6.1. MODBUS REGISTER MAP
Care should be taken when remotely controlling/configuring the 4003 via the MODBUS interface
as values set intentionally, or unintentionally, will immediately affect the operation of the 4003.
E.g. enabling relay inversion although a useful test will cause the relays to changeover and signal
an indicate an event when no event is active.
In general:
Setting a coil activates the function detailed.
Reading a coil, whose contents are set, indicates STATUS active.
COILS
REGISTER
STATUS/FUNCTION DESCRIPTION
10000 Pig Detected Indication Reference section 4.4
10001 Delete All Events Reference section 4.5.3
10002 Enable Low Power Mode Low power enabled when set
10003 Invert Relay Polarity Refer to Section 4.5.13