Varec 8315 Series manual Out

8300		8315 L&J Tankway Software Description
	Dynamic Parameters	Function
	NumTimeouts	Number of unresponded requests issued before the scanner timed
		out.
	NumScanList	Number of points in the Scan List
	PntStatus	Byte value indicating status of point. Values are:
		0: No Error
	PntCheckSum	CRC-16 Checksum for point’s static Configuration Parameters

4.20.2Application

The LJSCAN point monitors the status of the Model 8315 Tank Gauge Interface. The LJSCAN point is created automatically by the Model 8315. The point number will correspond to the Module such that LJSCAN.1 is created for module 1 (the 8315’s unit address DIP switch = 1). Use the Upload command to retrieve the data from the LJSCAN point or any other points created automatically by the RTU.

The NumRequests parameter gives the total number of requests attempted, while the NumTimeouts and NumComErrors are the number of time-outs and communications errors. The ID is the current gauge ID being scanned. The Pnt parameter is the Tag of the LJ1000, LJ1500 or LJ2000 point associated with the point being scanned.

This point can set the type of engineering units for the level and temperature data (English or Metric). By setting the LevelConvert and TempConvert the Level and Temp can be changed from English to Metric or vice-versa. If the LevelConvert and TempConvert are not set, no conversion will be performed.

The user can also set the delay between each poll as well as how long to wait for a transmitter to respond. If a transmitter is not responding, it will no be polled as often as transmitters that are on-line. The HoldOff parameter determines how often the off- line transmitter will be polled. For example, if the HoldOff is 10, then a transmitter that is off-line will be polled only one tenth as often as a transmitter that is on-line.

The ScanTimeout parameter is used by LJ1000, LJ1500 and LJ2000 points to determine if there have been no good readings for a specified period of time.

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