sample high/
sample low
(analog I/O)
For analog inputs, the sample high parameter defines the number of consecutive samples the input
signal must be above the threshold before a signal is considered active. Sample low defines the number
of consecutive samples the input signal must be below the threshold minus hysteresis before a signal is
considered deactivated. The sample high and sample low parameters are used to avoid unwanted input
transitions.
sample high/
sample low
(discrete I/O)
For discrete inputs, the sample high parameter defines the number of consecutive samples the input
signal must be high before a signal is considered active. Sample low defines the number of consecutive
samples the input signal must be low before a signal is considered low. The sample high and sample
low parameters are used to create a filter to avoid unwanted input transitions. The default value is 0,
which disables this feature. The value range is 1 through 255.
sample interval/
rate
The sample interval, or rate, defines how often the Sure Cross device samples the input. For battery-
powered applications, setting a slower rate extends the battery life.
sample on
demand
Sample on demand allows a host system to send a Modbus command to a register and require the
inputs to immediately sample the sensor and report readings back to the host system and/or Gateway.
Sampling on demand can be used between the normal periodic reporting.
The sample on demand feature requires using a host-controlled system capable of sending Modbus
commands to the master radio.
signal-to-noise
ratio (SNR)
The signal-to-noise ratio is the ratio of the signal to any background noise or noise generated by the
medium. In radio terms, it a ratio of the transmitted radio signal to the noise generated by any
electromagnetic equipment, in particular the radio receiver. The weaker the radio signal, the more of an
influence noise has on radio performance. Like gain, the signal-to-noise ratio is measured in decibels.
The equations for calculating SNR are:
SNR = 20 × log (Vs/Vn) where Vs is the signal voltage and Vn is the noise voltage;
SNR = 20 × log (As/An) where As is the signal amplitude and An is the noise amplitude; or
SNR = 10 × log (Ps/Pn) where Ps is the signal power and Pn is the noise power.
single-point
ground
All grounds within a system are made to a single ground to avoid creating ground loops.
site survey
Conducting a site survey, also known as a radio signal strength indication (RSSI), analyzes the radio
communications link between the Gateway (or master radio) and any Node (or slave radio) within the
network by analyzing the radio signal strength of received data packets and reporting the number of
missed packets that required a retry.
slave ID
The slave ID is an identifying number used for devices within a Modbus system. When using more than
one Modbus slave, assign each slave a unique ID number.
By default, Gateways are set to Modbus Slave ID 1.
sleep mode
During normal operation, the Sure Cross radio devices enter
sleep mode
after 15 minutes of operation.
The radio continues to function, but the LCD goes blank. To wake the device, press any button.
slow scan mode
(All internal battery models)In slow scan mode, the device enters a deeper sleep mode to conserve
battery power after the device loses its communication link with its parent or master radio. The device
wakes up periodically to search for its parent radio. If a parent or master radio is not found, the device
goes back to sleep for another sleep cycle. If the parent or master radio is detected, the device exits
slow scan mode. To manually exit slow scan mode, press the binding button.
Sure Cross
®
DXM100-Sx Wireless Modbus Slave
www.bannerengineering.com - Tel: + 1 888 373 6767
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