Neptune Technology TRICON SmartTrol, Руководство по установке и обслуживанию

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Baud Rate
The Baud Rate is the communication rate in bits / seconds. It must be selected to match
the host computer Baud Rate. You can set the rate to any of the following values: 300, 600,
1200, 2400, 4800, or 9600 baud.
Parity
Parity is a form of error checking in the data transmission. The parity (even, odd, mark,
space) should match the host computer.
Analog Output
For SmartTrols with the analog output option, this function allows setting of the output
scale. The SmartTrol produces the 4-20 mA output based upon the display Rate and uses
low and high limits to set the range of the output. For a Trident Turbine, the low limit could
be “0” (corresponding to the zero flow) and the high limit could be set to “1000”
(corresponding to 1000 GPM flow rate at maximum continuous flow). These values would
set the output to 4 mA when zero flow occurred and 20 mA when the flow rate went to
1000 GPM.
The low and high limits may be customized to the application to provide higher resolution
of the flow rate if the full range of flow rates is not used. If the flow rate was never less than
20 GPM and never more than 600 GPM, these values could be set to correspond to the 4
and 20 mA output levels respectively. For flow values in between the low and high
setpoints, the output current is offset and proportionately scaled.
Relay Operation
This function sets all parameters associated with relay operations with the exception of the
actual preset values which will trigger the relays. Relay durations may be set in seconds or
minutes. Relay A may be set to use the displayed value of Rate, Total, or Grand Total in
comparison to the Preset A value. Relay B is independently set to use the display value of
Rate, Total, or Grand Total in comparison to the Preset B value.
For each relay, if the comparison is selected as Total or Grand Total, then set a duration
value ranging from 0 to 99. If 0 is selected as the duration value, then the relay is latched
on after reaching the endpoint. For each relay, if the comparison is selected as Rate, then
the relay closes whenever the Rate exceeds the preset value and open when the Rate falls
below the preset value. Since the normally-closed and the normally-open contacts of the
relay are available, use this feature for both over and under Rate alarming.
30 TRICON
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SmartTrol™ Installation and Maintenance Guide
Chapter 9: Using the Worksheet