User manual

User Manual
man_905K_1.10.doc Page 9
Examples: electricity metering, fluid flow, raingauge, level from a shaft encoder
Analog continuously variable signals (0-20mA, 4-20mA, 0-10mA, 0-10V)
Examples: measured tank level, measured process temperature
Some internal signals may also be transmitted to outputs in the network:
• Setpoint Status (digital signal set or reset depending upon the value of the analog signal
compared to a high and a low setpoint value configured in the 905K)
• Supply Low Voltage (digital signal set when supply voltage is low).
• Supply Voltage (analog value)
• Pulse Rate (analog value proportional to rate of pulse input - available for both pulse inputs)
1.2 Power Supply
The power consumption of the 905K is very small as it conserves power by reverting to “sleep”
mode between transmissions. The 905K can be powered from a 6 - 30 VDC supply. An optional
9VDC battery pack, the BU-5 is available to power the 905K. The battery supply uses six AA
alkaline batteries. More than one BU-5 battery pack can be connected together to supply a 905K.
Other battery supplies can also be used to power the 905K, including a solar panel supply.
The 905K unit provides an internal alarm on low supply voltage - this alarm may be transmitted
by radio for warning purposes. The user can configure the voltage at which the low voltage
alarm activates.
The 905K generates a 24VDC, 50mA supply for powering the analog loop. This supply is
designed to power an analog loop only and should not be used for any other purpose.
1.3 Radio Transmitter
The 905K has an internal frequency hopping radio transmitter that operates on a unlicensed radio
channel at 900 MHz. A radio licence is not required for the 905K in USA, Canada, Australia,
New Zealand and some other countries.
It is suitable for use in utility industries such as electricity, water and gas, as well as a cost
effective solution for short range applications in factories and industrial plants.
To extend radio range, 905U modules can be used as repeaters. Up to five repeaters can be
configured for each input-to-output link. The configuration is done at the 905K module where
the input signal is - no additional configuration is required at the 905U modules. The transmitted
radio message will include the address of repeater modules - modules with these addresses will
re-transmit the messages.
1.4 Configuration
Each module must be configured before it can be used. Configuration is performed using a PC
(or a laptop computer) connected to the module via the internal RS232 port on the 905K. 905K