BacnetNumericInput Function Block

The BacnetNumericInput exposes a raw object over BACnet as ‘Analog Input’ BACnet object.

Figure 1: BacnetNumericInput Function Block

Figure 2: BacnetNumericInput Property Sheet

Inputs

Input Name

Description

In

It is a 32-Bit floating input point.

Table 1: Inputs of BacnetNumericInput Function

Outputs

Output Name

Description

Out

When Out of Service is "false"- Out is In value.

When Out of Service is "true"- Out is the Present Value written over BACnet.

Status Flags

Displays the status of this function block. It can be any one or a ‘ OR’ combination of the following values:

1 - In Alarm

2 - Fault

4 - Overwritten

8 - Out of Service

Example:

A value of 1 means the function block is in In Alarm state.

A value of 9 means the function block is in Out of Service as well as in In Alarm state.

Event State

Displays the present event state of this function block. It can be any one of the following values:

0 - Normal

1 - Fault

3 - High Limit

4 - Low Limit

Out of Service

Shows whether the function block is in out of service state or not.

Out of Service is modifiable over BACnet. Setting Out of Service to "true", decouples In from Out, i.e. In values no longer shows up on Out.

When Out of Service is "true", Out can be overwritten over BACnet (via Present Value property).

Table 2: Outputs of BacnetNumericInput Function

Parameters

Parameter Name

Description

Units

Defines the Out-values engineering unit.

Cov Increment

Defines the delta value change in Out, that will trigger COV update notifications to other recipients on the BACnet bus.

Time Delay

Defines the Time delay (in seconds) with which a High Limit/Low Limit/Normal transition will be set off, once conditions are met.

Notification Class

There are four notification classes:

  • Urgent

  • High

  • Low

  • User Defined

High Limit

Defines the High Limit.

When Limit Enable High Limit is defined "true", if Out value exceeds this limit and the condition exists for at least the defined Time Delay period, then -

  • Event State is changed to High Limit.

  • Status Flags is set to In Alarm.

  • An event notification is sent to all recipients listed by the Notification Class (if Event Enable to Off Normal is defined true).

Low Limit

Defines the Low Limit.

When Limit Enable Low Limit is defined "true", if Out value falls below this limit and the condition exists for at least the defined Time Delay period, then -

  • Event State is changed to low Limit.

  • Status Flags is set to In Alarm.

  • An event notification is sent to all recipients listed by the Notification Class (if Event Enable to Off Normal is defined true).

Deadband

Defines the value of the Deadband.

While transitioning from an off normal state (‘High limit’/‘Low Limit’) to ‘Normal’ state ‘Out’ value must remain between the range - (‘Low Limit’ + Deadband) and (High Limit - Deadband) for at least the defined Time Delay period, then only -

  • Event State is changed to Normal.

  • Status Flag is cleared-off of In Alarm.

  • An event notification is sent to all recipients listed by the Notification Class (if Event Enable To Normal is defined true).

Limit Enable Low Limit

Setting it to "true" enables detection of low limit alarm based on configured Low Limit value.

Limit Enable High Limit

Setting it to "true" enables detection of high limit alarm based on configured Hight Limit value.

Event Enable to Off Normal

Setting it to "true" enables sending of event notification of Off-Normal event transitions to recipients listed by the Notification Class over BACnet.

Event Enable to Fault

Setting it to "true" enables sending of event notification of Fault event transitions to recipients listed by the Notification Class over BACnet.

Event Enable to Normal

Setting it to "true" enables sending of event notification of Normal event transitions to recipients listed by the Notification Class over BACnet.

Notify Type

Define one of the two notify types-

  • Alarm - Makes all the BACnet event notifications originating out of this instance of function block, of type ‘Alarm’.

  • Event - Makes all the BACnet event notifications originating out of this instance of function block, of type ‘Event’.

Event Detection Enable

Setting it to "true" enables;

  • Detection of High Limit/ Low Limit/ Fault/ Normal events in ‘Event State’.

  • Setting/Resetting of In Alarm /Fault/ Overwritten/ Out of Service flags in Status Flags.

Setting it to "false" enables:

  • Event State will always remain Normal.

  • Status Flags will always remain 0.

Bacnet Object Instance

It shows the instance number of this BACnet object function block.

Enable Reliability

Setting it "true", enables detection of Open Loop / Short Loop states.

These states show up in Reliability property of this instance of the function block. Reliability property is only exposed over BACnet.

Out Save

Master Sync Enabled: If you set it to "true" the last output will be set as output for one cycle after the controller restarts. The application can use it to return to the same state before the controller restart.

Out: To enable or disable the Out feature.

Table 3: Parameters of BacnetNumericInput Function

Example

Figure 3: Example - BacnetNumericInput Function Block

Figure 4: Example - BacnetNumericInput Property Sheet

Refer to General Description for general information about IRMN4 Function Blocks.