DSEGenset DSE8610, Operator'S Manual

Page: 68 / 118

Description Of Controls
68
5.3.7 RS485 SERIAL PORT
This section is included to give information about the currently selected serial port and external
modem (if connected).
The items displayed on this page will change depending upon configuration of the module. You are
referred to your system supplier for further details.
NOTE: Factory Default settings are for the RS485 port to operating at 19200 baud, modbus
slave address 10.
Module RS485 port configured for connection to a modbus master.
DSE86xx series modules operate as a modbus RTU slave
device.
In a modbus system, there can be only one Master, typically a
PLC, HMI system or PC SCADA system.
This master requests for information from the modbus slave
(DSE86xx series module) and may (in control systems) also
send request to change operating modes etc. Unless the Master makes a request, the slave is ‘quiet’
on the data link.
The factory settings are for the module to communicate at 19200 baud, modbus slave address 10.
‘Master inactivity timeout’ should be set to at least twice the value of the system scan time. For
example if a modbus master PLC requests data from the DSE86xx modbus slave once per second,
the timeout should be set to at least 2 seconds.
The DSE Modbus Gencomm document containing register mappings inside the DSE module is
available upon request from support@deepseaplc.com. Email your request along with the serial
number of your DSE module to ensure the correct information is sent to you.
Typical requests (using Pseudo code)
BatteryVoltage=ReadRegister(10,0405,1)
: reads register (hex) 0405 as a single register (battery volts)
from slave address 10.
WriteRegister(10,1008,2,35701, 65535-35701)
: Puts the module into AUTO mode by writing to (hex)
register 1008, the values 35701 (auto mode) and register 1009 the value 65535-35701 (the bitwise
opposite of auto mode)
Shutdown=(ReadRegister(10,0306,1) >> 12) & 1)
: reads (hex) 0306 and looks at bit 13 (shutdown alarm
present)
Warning=(ReadRegister(10,0306,1) >> 11) & 1)
: reads (hex) 0306 and looks at bit 12 (Warning alarm
present)
ElectricalTrip=(ReadRegister(10,0306,1) >> 10) & 1)
: reads (hex) 0306 and looks at bit 11 (Electrical
Trip alarm present)
ControlMode=ReadRegister(10,0304,2);
reads (hex) register 0304 (control mode).