Metal Samples MS2700E, Руководство оператора

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i. Baud Rate and Default Communication Parameters
The default communication parameters for the MS2700E transmitter are provided in Table 4 below. If
necessary, the baud rate can be changed using Positions 1 and 2 of Switch 2, as illustrated in Table 3.
Parameter Value
Baud Rate 19200
Data Bits 8
Parity Even
Stop Bits 1
Table 4. Default Communication Parameters
ii. Device Address
Up to 32 MS2700E transmitters may be connected in a multi ‐ drop network (“daisy ‐ chained”) using a
single cable run. However, each transmitter must be set to a unique device address to avoid conflicts.
This is done using Positions 3 through 7 of Switch 2, as illustrated in Table 3.
CAUTION:
Be sure to observe the appropriate gas group rating listed on page 3 for stand ‐ alone or
multi ‐ drop operation.
iii. Communication Protocols
The MS2700E transmitter offers user ‐ selectable RTU or ASCII communication protocols, giving the unit
a broader range of compatibility. The communication protocol is set using Position 8 of Switch 2, as
illustrated in Table 3.
iv. Termination Resistor
To ensure proper operation, the RS ‐ 485 network must be terminated properly with a termination
resistor. To facilitate this, each MS2700E transmitter has a built ‐ in 120

termination resistor that can
be switched on or off using Position 10 of Switch 2. Once all units have been installed, be sure to
enable the termination resistor of the last unit in the network. The termination resistors of all other
transmitters should be turned off.
v. Data Registers
Table 5 lists the data registers of the MS2700E transmitter.
No Register Address Description
1 40001 Device Status
2 40002 Device Address
3 40003 Baud Rate
4 40024 DAC Value
5 40026 Probe Switch Setting
Table 5. Modbus Data Registers