Property
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Notes
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RefName
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Use the default reference name unless you want a more descriptive name for this microblock for graphics, source tree rules, or network links. All reference names in a control program must be unique.
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Network Visible?
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When you set Network Visible? to Yes, the microblock's output is visible to third-party equipment.
Any BACnet device on the network can read or change the value of this output as long as the device uses a priority higher than 16 (or, if the lock parameter is set to Y, a priority higher than 8).
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(Display) Name
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The microblock label used in the interface. You can use any characters (including spaces) in this field, except for the " character.
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Description
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BACnet-visible description of the microblock.
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Expander
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Indicates the number of the expander module (normally 0-5 or 0-6). The Technical Instructions document for your hardware device or the Technical Handbook can provide you with guidelines for determining the Expander. These settings can be adjusted on the Properties page; however, these settings should not need to be adjusted after the initial installation unless the input point on the device is changed.
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Output Type
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Set Output Type to match the equipment output type the microblock will read.
Binary
- Relay/Triac Output
- Pneumatic 064 PSI
Analog
- Electrical 010 Volt
- Pneumatic 064 PSI
Electrical 020 mA
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Output Number
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Set the Output Number to match the equipment input number the microblock will read.
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Units
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The Units field has two parts, a scrolling list and a number field. If the unit of measure that you need is not available in the scrolling list, enter a BACnet number in the number field. Units can be read directly from the BACnet object but setting this property in the microblock reduces network traffic.
Units, abbreviations, and BACnet numbers
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Minimum Value Maximum Value
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You can use Minimum Value and Maximum Value to set the actuator limits for the equipment.
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Resolution
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The smallest recognizable change, in engineering units, for the equipment.
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COV Increment
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The COV (Change of Value) Increment is the minimum change in the present value that will cause a microblock to send data to its COV Subscribers.
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Full Travel time
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The Full travel time is the time it takes for the actuator to travel from fully open to fully closed. This setting can be adjusted on the Properties page using the Full Span property. The example below shows how the Full travel time affects the microblock's operation.
Example
The Full travel time of an actuator is 100 seconds, and the value of the Floating Motor microblock is 10%. The motor is activated for 10 seconds to achieve a 10% open status. The value of the Floating Motor is later increased to 30% as the zone temperature increases. The motor is then activated for an additional 20 seconds to achieve a 30% open status (30% - 10% = 20% = 20 seconds).
NOTE The Floating Motor microblock will not send a signal shorter than one second. If you need to control the accuracy of the actuator's position to within 1%, you must use an actuator with a travel time of at least 100 seconds. For example, if your actuator has a 20 second travel time, it can only be adjusted in increments of 5% (1 second/20 seconds = 5 seconds/100 seconds or 5%).
If the Full travel time is inaccurate, the calculated position of the actuator will also be inaccurate. Over time, multiple adjustments can cause the error to be quite large and affect the ability of the equipment to efficiently achieve the desired setpoint. For this reason it is recommended that you program the control program to allow the Floating Motor microblock to recalibrate itself by using a value of 0% or 100%. When the microblock's value is either 0% or 100%, the microblock recalibrates by sending an additional signal for the full duration of the travel time to ensure that a fully open or fully closed position is obtained.
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Min Pulse Width
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The Min pulse width setting (Min Pulse on the Properties page) indicates the minimum amount of time the motor should be activated anytime it moves. When the Floating Motor microblock receives a new position, if the time required to move that amount is less than the Min pulse width, the microblock will not activate the motor.
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Maintain Contact Closure
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The Maintain contact closure setting allows you to determine whether the motor should remain activated after it has recalibrated itself at 0% or 100%. This setting can be adjusted using the Maintain OPEN at 100% and CLOSE at 0% parameter on the Properties Page. If this is set to yes, the motor remains activated after it has reached its limit of 0% or 100%. If this is set to no, the motor will stop after recalibrating to its fully open or closed position. If this is set to no when the device is restarted or when the Floating Motor microblock has a value of 0% or 100%, then the Properties Page Text Proceeding with power up initialization appears.
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Editing Privilege
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Preset (the default Editing Privilege) indicates that each property in a microblock has an appropriate privilege assigned to it.
If you change the Editing Privilege, all the properties in that microblock are assigned to that one editing privilege, which is not always desirable.
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