Westermo RM-505U-2-E - Manual (Page 6)

505U Radio Telemetry Module
Page 6 © September 2002
1 OVERVIEW
The 505U radio telemetry module is an economical solution for the remote monitoring of process
signals. The 505U can connect to digital, pulse or analogue signals from process transducers, and
transmit these signal values by radio.
Although the 505U is intended to be simple in its application, it also provides many sophisticated
features. This manual should be read carefully to ensure that the modules are configured and
installed to give reliable performance. The 505U uses the 105U module as a receiver, or repeater.
If you have not used 105U modules before, please read the 105U User Manual prior to reading
this manual.
The 505U module is a monitoring only unit - that is, it will only accept input signals and does
not provide output signals. The 505U has an internal radio transmitter; it does not have a receiver to
receive messages from another module.
The 505U transmits the value of an input signal whenever the signal changes, and also after a pre-
configured time. Each transmission message includes error-checking to confirm the validity of the
message. At each transmission, the 505U may be configured to repeat the transmission several
times to ensure that the transmission is received correctly. This is important if the radio path is
marginal (that is, the radio signal is not strong) or if there is a lot of radio traffic on the radio channel
which may corrupt the 505U message. The 505U transmits the input message to a 105U module,
which sets an output signal to be the same value as the 505U input, or the 105U passes the input
message to another device (PC or PLC) via its serial port.
For more information on the 105U module, please refer to the 105U User Manual.
1.1 Available Models
The 505U has a heavy duty painted aluminium enclosure, weather-proof to IP66. Signal and power
connections to the unit are made via a weatherproof connector at the bottom of the module.
Antenna connection is made using a BNC coaxial connector at the top of the module.
External 12VDC supply
505U-2-E two digital/pulse inputs plus one analogue input
3.5 – 5VDC battery supply (batteries not included)
505U-2-B two digital/pulse inputs plus one analogue input
1.2 Input Signals
The 505U-2 model provides two digital/pulse inputs and one analogue input for connecting to
process transducers.
Digital Signals