Accumulator (Counter Input) Attributes - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 15.0

Controller Tool Help

Product name
Controller Configuration Tool
Document type
User Guide
Document number
LIT-12011147
Version
15.0
Revision date
2022-11-18

Table 1 describes the Accumulator object attributes. These attributes are displayed in alphabetical order. See Object Attributes in the Input and Output Objects section for descriptions of the data provided in this table. Unless otherwise stated, the attributes listed in this table appear in the Details dialog box (for example, the Present Value appears in the Control View below the module name in Simulation and Commissioning modes).

Table 1. Accumulator Attributes

Name

Type

Mode

Description

Debounce

Input

All Modes

Indicates the length of time that the hardware input must remain in a state for the connected object to detect that a change has occurred. The hardware contact may bounce, producing extra input pulses. You can use the Debounce attribute to eliminate these nuisance input pulses. Contact fluctuations are ignored and, thus, filtered during this time period.
Note: Debounce is an attribute of only an MS/TP Accumulator (Counter Input).

Description

Input

All Modes

Indicates the description provided for the object.

Device Type

Input

All Modes

Describes the physical network device to which the object is connected.

Limit Monitoring Interval

Input

Configuration

Specifies the monitoring period in seconds for determining the Pulse Rate. The Pulse Rate is the number of pulses received during the previous Limit Monitoring Interval period.

Max Value

Input

All Modes

Specifies the maximum amount for Present Value (appears as O1).

Name

Input

All Modes

Indicates the name of the object.

Object Identifier

Input

All Modes

Indicates the instance number of the Object Type as exposed to the network. The Object Identifier must be unique within the host device.

The Object Identifier consists of the BACnet Class ID and the object’s Instance Number separated by a colon. For example, an Object Identifier of AV:10026 has a BACnet Class ID of AV and an Instance Number of 10026.

Offline

Input

Commissioning

Indicates if the object is currently communicating with the network device.

This attribute is visible in an SAB device.

Out of Service

Input

Simulation

Commissioning

Indicates whether the object is currently connected to the hardware or offline (out of service).

This attribute is visible in an SAB device.

Periodic Update

Input

All Modes

Specifies the amount of time between evaluation of updates to Present Value (appears as O1), Reliability, and Status.

Default Value: 60 seconds

Range: 1 - 10,000 seconds

Prescale

Input

Configuration

Indicates the coefficients used to convert the accumulated pulses into the Present Value. This attribute uses moduloDivide integer division (where 5/2 is 2 with a remainder of 1; the integer division is carefully implemented to avoid round-off errors by carrying the remainders forward in the calculation). The algorithm used is

Present Value = (prescale.multiplier x accumulated-pulses*)/prescale.moduloDivide.

* The accumulated-pulses value in this calculation includes the remainder from the moduloDivide integer division calculation.

Present Value (Appears as O1)

Input

Simulation

Commissioning

Indicates the prescaled pulse count. The raw pulse count is adjusted by the Prescale calculation to arrive at the Present Value. Changes in Present Value generate a COV when the Periodic Update expires.

Present Value is saved once per day, and returns to the last saved value during a restart. For controllers with fast persistence, present value may be saved up to once per second.

Note: The Present Value is saved and does not return to the default value after a transfer to the computer and a transfer to the device with the tool.

This attribute is a calculated value (Output).

Reliability

Input

Simulation

Commissioning

Provides the following values to indicate whether or not the Present Value (appears as O1) is reliable:
  • Offline: The input hardware is offline.
  • Connection Fail: The object fails to connect to the hardware.
  • Reliable: The object is neither of the above.
If an Out of Service command is received, this attribute is Reliable. Only when the object is out of service can you write values to this attribute.

Set Name: Reliability

This attribute is a calculated value (Output).

Status

Input

Simulation

Commissioning

Reflects the status of the object based on the Reliabilityattribute and the status of any commands.

Possible values for Accumulator objects are:
  • Out of Service: Out of Serviceis True.
  • Unreliable: Reliability is not reliable.
  • Normal: Neither of the above is correct.
Set Name: Status

This attribute is a calculated value (Output).

Units

Input

All Modes

Specifies the units of measure for Present Value (appears as O1).

Use Default if Not Reliable

Input

All Modes

Specifies the behavior when the Source is not reliable. If True, the Output is set to its Default Value whenever its Source is not reliable and its Reliability is marked as Reliable. If False, the Output maintains its last reliable value and its Reliability reflects the reason that the source is not reliable.

Value Set Input Commissioning

Use to reset the Present Value. The Present Value attribute gains its value from the value written to the Value Set attribute.