Westermo RM-505U-K - Manual (Page 13)

man_505U-K_1.4.doc Dec 2008
    ELPRO Technologies Pty Ltd 2008 Page 13
transmit the analogue value.
The sensitivity value should be selected which is more than the normal analogue signal noise.
If the sensitivity is less than the signal noise, then the 505K will send a lot of un-necessary
transmissions, possibly resulting in jamming the radio channel.
An update transmission of the analogue value will be transmitted if the analogue value has not
been transmitted for during the user-configurable update period (10 seconds - 7 days). If an
update time of zero is selected, then no update messages will be sent.
If the update time expires since the last transmission, then the last measured value will be
transmitted - that is, a new measurement will not be taken. Normally the update time will be
much longer than the sample time. If the update time is less than the sample time, then update
messages may transmit the same value as the previous transmission, as a new measurement
has not yet been taken.
Overview:
• Measurements of the analogue signal are determined by the sample time and warm-up time
• Analogue value is transmitted if the measured value has increased by the configured
sensitivity amount since the last transmission
• Analogue value is transmitted if the input value has not been transmitted within the update
time (10 seconds – 7 days)
• There is no paralysis time for the analogue input.
2.4.6 Setpoint Status
The setpoint status is an internal status value, calculated by comparing the analogue input to
two configurable setpoint values. The setpoint status turns ON when the analogue input
moves below the low setpoint value, and turns OFF when it moves above the high setpoint
value. The high setpoint percentage must always be greater than, or equal to, the low set
point.
The internal setpoint status will be determined every time an analogue measurement is taken.
The setpoint status is treated as a digital signal and its value is transmitted according to the
rules for a digital input.
2.4.7 Supply Voltage
The 505K measures the supply voltage and stores it as an internal “analogue” value. The
range of the analogue value is 0 – 30 volts. The measurement is made every time the radio
transmits (the measured value is the “loaded” supply voltage) and the measurement is
transmitted based on the user-configurable update time - there are no change transmissions
for this value.
2.4.8 Low Supply Voltage Alarm (Supply LowVolts)
If the voltage of the power supply falls below the pre-configured alarm value, the internal low
voltage alarm will turn on. The 505K provides user-configurable high and low setpoints for
the supply voltage value. If the supply voltage falls below the low SP, then the Supply Low
Volts status will turn on. When the supply voltage increases above the high SP, the status
will turn off. The low SP should not be set less than 5.7V.