Teledyne Oldham MX 16, User Manual

Page: 48 / 60

MX 16
ANALOG AND DIGITAL CONTROLLER
USER GUIDE
44 NP16EN
Revision: A.0
Transfer Table
Two types of information can be retrieved
via the RS485 output:
■
Information about sensor configuration;
■
Real-time sensor information (measurements, alarms, etc.).
1. Access to configuration information
It is possible to access the installation configuration (for example, to access the alarm thresholds
or the names of the sensors).
This configuration information is listed in the transfer table from address 0 to address 1999.
The address of the detectors is determined as follows:
■
For a digital sensor:
Sensor address = 1
■
For an analog sensor:
Sensor address = 257
Once the sensor address is known, the desired request can be executed by following the transfer
table below. For example, to find the instantaneous alarm threshold number 1 for a sensor, read
register number 52.
All of the information at addresses 1 to 52 will be accessed. The 52
nd
word corresponds to the
expected value.
Example
Access instantaneous alarm 1 for the sensor located on line 2 at address 2 of unit 2.
A. Determination of the sensor address: 1
B. Structure of the
Modbus request:
- Slave number for the unit (defined by
factory)
02 = 0x02
- Operating type (03 = read) 03 = 0x03
- Sensor address 1 = 0x0001
- Number of words to read (see Excel document) 52 = 0x3A
- CRC
Thread: 0x02 0x03 0x00 0x22 0x00 0x3A 0xCRC 0xCRC
2. Access to real-time information
Measurement and alarm information from the detectors is listed in the transfer table from address
2000 to 65535. The sensor measurements are available at addresses 2001 to 2264, the sensor
statuses are available at addresses 2301 to 2564 (alarm 1, alarm 2, etc.).