User manual

915U-2 Wireless I/O Page 13
Page 13 User Manual
The 915U-2 modules transmit the input/output data using radio or Ethernet. The data
frame includes the "address" of the transmitting module and the receiving module, so
that each transmitted message is acted on only by the correct receiving unit. Each
message includes error checking to ensure that no corruption of the data frame has
occurred due to noise or interference. The module with the correct receiving "address"
will acknowledge the message with a return transmission (acknowledgement). If the
original module does not receive a correct acknowledgement, it will retry 1 to 5 times
(default is 3) before setting the communications fail status of that message. For critical
messages, this status can be reflected on an output on the module for alert purposes.
The module will continue to try to establish communications and retry, each time an
update or change-of-state occurs.
A system can be a complex network or a simple pair of modules. An easy-to-use
configuration procedure allows the user to specify any output destination for each input.
The 915U-2 comes from the factory with ELPRO WibMesh protocol as standard, this
protocol provides enhanced features, including IP addressing, allowing thousands of
modules to exist in a system, and allowing automatic routing of messages through
repeater stations.
The module can also be configured with the Legacy WibNet protocol which provides
operation with existing ELPRO wireless I/O devices (905 series and 105 series
modules). Please see separate WibNet configuration Supplement for details.
The module can easily be switched between the two versions by selecting the
appropriate protocol from an inbuilt web page.
Each 915U-2 radio can have up to 24 expansion I/O modules (ELPRO 115S) connected
by RS485 twisted pair provided there is sufficient power to power all modules with I/O.
Any input signal at any module may be configured to appear at any output on any
module in the entire system.
Modules can be used as repeaters to re-transmit messages on to the destination
module. Repeaters can repeat messages on the radio channel or from the radio
channel to the serial channel (and serial to radio). The meshing protocol will
automatically select other stations to act as repeaters if required (up to ten hops). Using
Legacy protocol, up to five repeater addresses may be configured for each input-to-
output link.
The units may be configured via Ethernet using a web browser or via USB port and
system configuration software. The software configuration is defined in Chapter 4 -
Configuration.
For web based configuration consult separate Web Page configuration Supplement.