CONTROL SOLUTIONS ValuPoint 4, Руководство пользователя

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another BACnet client subscribes to this object’s COV with a simple Subscribe COV.
This initial increment will remain in effect until some other BACnet client writes a new
COV increment to this object. If the BACnet client does a Subscribe COV Property,
then the COV increment specified in the subscription is used instead of this Initial COV
Increment. COV Increment applies only to Analog objects. COV will be reported on any
change in a Binary or Multi-state object.
Initial Relinquish Default – The Initial Relinquish Default will take effect when the
ValuPoint is first powered up. After that, any BACnet client can write a new Relinquish
Default value to the object. The Relinquish Default value applies to any Commandable
object, and the Present Value of the object will assume this value when all 16 priorities
have been relinquished.
Slope/Scale Factor – Scaling applies the formula y=mx+b. When reading from the
slave, the raw data as read is multiplied by the scale factor, then the offset is added to
produce the resulting Present Value. When writing to the slave, the offset is first
subtracted from Present Value, and that result is divided by the scale factor to produce
the raw data actually written to the slave device. NOTE: If no scale factor is given
(zero is entered), no scaling will be done, as if slope=1 and intercept=0.
Intercept/Offset – The offset portion of the scaling as noted above.
Delta for Send – Enter the threshold for writing when configured to Write on Delta. If a
value of 5.0 is entered, the value must change by more than 5.0 before the slave
device will be written to. Delta applies only to Analog objects. Binary and Multi-state
objects will send on any change when Write on Delta is enabled.
Default Timeout (Sec) – Timeout for Modbus slaves is specified on the Modbus page.
When the slave device is another BACnet device, the timeout given here specifies the
amount of time the ValuPoint will wait for a response before calling it an error.
Max. Quiet Time (Sec) – This is applicable to an object which is set to Write on Delta.
The result is that if there has been no change within this amount of time, the slave
device will be re-written anyway. In addition to entering a nonzero value here, you
must check the ‘Enable Max Quiet Time’ box.
Default Value – This is the value that should become the Present Value upon power-up
or upon communications failure, if either of these options are selected by the
appropriate check boxes above.
Read Fails before Fault – When ‘Set Default on Comm Fail’ is checked, this entry will
allow you to disregard a small number of spurious errors. At least this many errors
must occur consecutively before a fault will actually be flagged. Causing a fault as a
result of a single instance of spurious noise on a communication line can be a
nuisance. This setting allows quieting the nuisance fault notifications. (This parameter
does not apply to physical I/O.)
8. Object Map Page file:///C:/AAA_CSI/Literature/2016 User Guides/VP4-BACnet User Gui...
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