GE Hydran 201i Instruction Manual page 74

• SupervisoryLink: Use this channel if the H201Ti must be set to Hydran protocol
and has to communicate with an H201Ci Controller.
• LocalUSB MODBUS: Use this channel if the H201Ti must be set to ModBus
protocol and has to be connected directly to a host computer running the
Perception software. For this connection, use the H201Ti's USB female connector
located on the side of the CPU module. The USB link is used only occasionally or
for brief periods of time during the initial verification or maintenance procedures.
• SupervLnk MODBUS: Use this channel if the H201Ti must be set to ModBus
protocol and has to be connected via an USB to RS-485 converter to a host
computer running the Perception software or to communicate with an H201Ci
Controller.
Note: The H201Ti's microprocessor only gives access to one channel at a time.
5.5.6.2 Comm Mode
This function is used to select the communication mode between the Hydran 201Ti and
the Hydran Host software. There are two possibilities:
• Call OnAlarm: In this mode, the H201Ti communicates with the Hydran Host
through a telephone line when a gas or fail alarm condition is detected. The
operation of this mode can be tested using the Communication; Force HostCall
command (see Section 5.5.6.5). The frequency and number of call attempts meet
the normal regulations of telephone companies.
• AnswerOnly: In this mode, the H201Ti remains inactive until being questioned by
the host computer running the Hydran Host or any other SCADA system.
5.5.6.3 MODBUS Parity
This function is used to select the ModBus Parity communication setting and it can be
set at None, Odd or Even.
This setting is relevant and shall be properly configured only when the Comm
Channel and Default Channel are set to LocalUSB ModBus or SupervLnk MODBUS. Else,
when 201Ti is set to Hydran protocol (Comm Channel and Default Channel are Local USB
or Supervisory Link), this setting is ignored.
5.5.6.4 Baud Rate
This function is used to set the serial communication rate of the Hydran 201Ti. The
communication can be set at 1,200, 2,400, 4,800 or 9,600 bps (bits per second). All
H201Ti's belonging to one network must be set to the same baud rate.
If the BaudRate parameter is changed and if the H201Ci Controller is equipped with a
modem, always execute the Communication; Force HostCall command (see Section
5.5.6.5 below) immediately after the modification.
Note: The communication rate of the H201Ti's must be the same as the one set in the
Hydran Host software (see the Hydran Host Software Manual).
Page 74
Hydran* 201i Instruction Manual
MA-033 Rev. 14.0, 12-Nov-18