Ametek DMS-3K, Installation & Operation Manual

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Once your communications parameters are set, you can choose the type of output desired.
They are as follows:
Modbus RTU
The DMS-3K Modbus port supports both Master and Slave Modes. For either mode, the
Modbus implementation will transmit the status (On/Off) and timestamp of each event. The
transmitted alarms can be used to drive an AMETEK Annunciator, RTU, SCADA, PLC or other
device. Refer to Appendix A for details on Modbus Functions supported and the mapping of I/O.
The Modbus port supports device addresses of 1-255, a maximum Baud Rate of 19,200 and no
parity.
The DMS-3K can transmit ‘Events’ or ‘Alarms’
Events Mode: Select this to provide alarm status with a time and date stamp. The Modbus
data will include the following data (decoded).
Date Time Input # Time Sync Status Event Type
10/26/12 15:32:43.163 124 Sync On or Off Alarm or Normal
The Modbus interface requires six 16-bit registers for each event to provide the above event
information (year, month, day, hour, min, sec, msec, alarm #, time sync, etc..) 10 events are
returned per poll for a total of 60 registers per poll. The Modbus Start address can be
configured based on the application. The ending address will automatically be calculated for the
60 registers required. Refer to Appendix A for complete details.
Alarm Mode: Select this to provide Alarm Status (On/Off status per input). Alarm Status
is provided by reading 16-bit holding registers with a single bit designated per input or group of
inputs. The configuration screen shows every bit (0-15) of the 16 bit register and you can enter
a single alarm in any order you want or a group of alarms. In the figure below, the first bit (bit 0)
of the Modbus register 40001 will present the status of input 1 and the second bit will present
the status of a group of inputs (2,3,5,6,7,etc). When entering a group of inputs, any input in that
group that goes in alarm will activate that Modbus bit.
The last Modbus register is used to accept remote control pushbutton inputs from another
Modbus Device or transmit the DMS-3K control pushbutton to another Modbus Device.