已安装 modbus 和 modbus-cli，但收到以下错误：
modbus read 192.168.0.1 %MW100 5
modbus /var/lib/gems/1.9.1/gems/rmodbus-1.3.3/lib/rmodbus/tcp.rb:29:in `rescue in open_tcp_connection': Timed out attempting to create connection (ModBus::Errors::ModBusTimeout)
from /var/lib/gems/1.9.1/gems/rmodbus-1.3.3/lib/rmodbus/tcp.rb:24:in `open_tcp_connection'
from /var/lib/gems/1.9.1/gems/rmodbus-1.3.3/lib/rmodbus/tcp_client.rb:18:in `open_connection'
from /var/lib/gems/1.9.1/gems/rmodbus-1.3.3/lib/rmodbus/client.rb:23:in `initialize'
from /var/lib/gems/1.9.1/gems/modbus-cli-0.0.14/lib/modbus-cli/read_command.rb:83:in `new'
from /var/lib/gems/1.9.1/gems/modbus-cli-0.0.14/lib/modbus-cli/read_command.rb:83:in `execute'
from /var/lib/gems/1.9.1/gems/clamp-1.3.2/lib/clamp/command.rb:66:in `run'
from /var/lib/gems/1.9.1/gems/clamp-1.3.2/lib/clamp/subcommand/execution.rb:18:in `execute'
from /var/lib/gems/1.9.1/gems/clamp-1.3.2/lib/clamp/command.rb:66:in `run'
from /var/lib/gems/1.9.1/gems/clamp-1.3.2/lib/clamp/command.rb:140:in `run'
from /var/lib/gems/1.9.1/gems/modbus-cli-0.0.14/bin/modbus:6:in `<top (required)>'
from /usr/local/bin/modbus:23:in `load'
from /usr/local/bin/modbus:23:in `<main>'
有人可以帮我吗？