4-Master Channel

Enter the Master Channel name.

This is the name which appears in the user diagnostics menu, and is also see in an HCP diagnostic window if used with Elecsys HCP. 

In some configurations this may be listed as "Direct Master", which includes a few operational differences noted below. The main differences between the Channel Types are listed below:

Direct Master

• Global Scan Period
• One failed poll changes RTU comms status.

Direct Master Flex Scan

• Scan Period configured for each scan.
• All "effective" polls must fail before RTU comms status fails. 

Select the automatic polling method for the channel.

Automatic polling types supported are:

• Yes – polling started automatically upon power-up
• No – polling started manually through the MMI
• Link Based Poll – polling is started only after a P/R connection has been made from an HCP. 

Enter the response timeout in milliseconds.

Time in milliseconds to wait for a poll response before declaring the message failed.

For Network Circuits, if a scan fails because the socket is broken or interface is unavailable, then the Master Channel protocol will wait a period of time (Response Timeout * 2) to try the next IP address in the Circuit. 

Unused.

Enter the interpoll delay in milliseconds. Use this to add a delay between each poll sent by the channel to any field unit.

Time in milliseconds to wait between each poll. 

The Scan Effective Limit is the time (in seconds) defining which scans in the Scan Table are considered "effective" – meaning, polls which affect the status of the Field Unit if there are poll failures. Scan Table entries which have a Scan Period greater than the Scan Effective Limit do not mark the Field Unit offline when the scan fails.

For instance, if the Scan Effective Limit is configured for 30 seconds, then any scans defined with Scan Period <= 30 will be used to mark the Field unit online or offline. Scans with Scan Period greater than 30 will not mark the Field Unit offline even if they fail. The Scan Effective Limit only applies to the "Direct Master Flex Scan Table" version of the channel object.

A Scan Effective Limit of 0 disables this feature, thus all polls will affect the Field Unit status. 

Enter the network recovery period in seconds.

Time period to wait after an RTU fails, before attempting to re-establish communications with that RTU. This will take the device off scan, allowing other devices on the channel to be polled more frequently and not waste as much time retrying a failed device. 

Click the Edit Table button to define the order and selection of polls to be sent to all field units on this channel, independent of protocol. Field Unit configurations (Modbus, etc.) define the protocol-specific nature of the individual polls that are sent.

Only one Unit Address/Poll Record combination can be entered in the Scan Table. Any subsequent table entries with duplicate Unit Address/Poll Record will be ignored.

Scan Table details:

Unit Address - This is the Field Unit Address as configured in each field unit on this Channel. (To force the Scan Table to ignore the Scan Period, enter a Scan Table row with the Unit Address of -1.) 

Poll Record - This is the row number in the Poll Record in the Field Unit definition. The first row in a Poll Table is referenced as record 1. Only those polls which are to be polled continuously need to be listed in this Scan Table. 

Scan Period - Enter the scan period in seconds. The Scan Period is the amount of time to use for scheduling each scan (global for all scans in the Direct Master, or configured per scan row in the Direct Master Flex Scan Table). 

For the Direct Master, the channel will restart the scan table sequence after the Scan Period has expired. If the total time for a given channel exceeds the scan period, the next scan shall be scheduled immediately.

For the Direct Master Flex Scan Table, each poll is scheduled based on its own Scan Period. If the total time required for scans at any point is greater than allowed by the Scan Periods, the scans will operate as fast as possible. 

Setting a Scan Period to a negative number will disable a scan. However, the first entry in the Scan Table for each Unit Address should not be disabled, or it may not correctly set the Alive/Dead status of the unit. 

Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration.

Select the primary physical communication port for this circuit. 

The selected port must be defined as an object under Networks, where its Async port properties (baud rate, etc.) are also defined (see the section 4-Master Channel#Async Port).

The same port (e.g. COM1) may also be shared with certain other tasks, such as Terminal Server, and may be used with Virtual Ports.

Click the Edit Table button to edit the IP address or list of IP addresses to connect for the Field Unit(s) on this circuit. Entering multiple IP addresses will allow failover connections when one connection fails (all connections made to the same Master Network Port on different IP addresses). 

Destination Address Enter the IP address to connect.

The IP address must be in the same IP network or reachable via the Default Gateway or Route Table configuration.

Interface Enter the network interface over which to connect to this Destination Address. The network interface must match the Interface name in the ACE object (such as "Ether1") rather than the Linux interface name (such as "eth0").

Enter the field unit name.

Unit name is displayed in diagnostic menus and in an HCP diagnostic screen.  

Enter the actual field unit address which is configured in the device being polled.

Valid Modbus addresses 1 to 255.

Click the Edit Table button to edit the details of the RTDB definition.

Point Count – Enter the number of data points of this type to be allocated space in the database.

Field Format – Select the point data format:

Boolean – Boolean
UINT8 – Unsigned 8-bit integer (0 to 255)
SINT16 – Signed 16-bit integer (-32,768 to 32,767)
UINT16 – Unsigned 16-bit integer (0 to 65,535)
SINT32 – Signed 32-bit long integer
UINT32 – Unsigned 32-bit long integer
REAL32 – IEEE floating point (32-bit)
STRING32 – Each field contains up to 32 ASCII characters
STRING256 – Each field contains up to 256 ASCII characters
EVENT – Timestamped event data obtained from field device.

The following field formats are the same as the above but do not generate an RBE flag when the data changes, even if the Field Unit is set to Produce RBEs=Yes.

No-Rbe Boolean – Boolean
No-Rbe UINT8 – Unsigned 8-bit integer (0 to 255)
No-Rbe SINT16 – Signed 16-bit integer (-32,768 to 32,767)
No-Rbe UINT16 – Unsigned 16-bit integer (0 to 65,535)
No-Rbe SINT32 – Signed 32-bit long integer
No-Rbe UINT32 – Unsigned 32-bit long integer
No-Rbe REAL32 – IEEE floating point (32-bit)
No-Rbe STRING32 – Each field contains up to 32 ASCII characters
No-Rbe STRING256 – Each field contains up to 256 ASCII characters

Data Address – Enter the address of the starting register within the RTDB for the Field Format and Count defined on this row.
The RTDB fields must be defined so they are non-overlapping, and there need to be enough data points defined to hold all of the data returned in the Poll Table entries defined for this FieldUnit.
All RTDB database fields (except String types) may hold 32-bit data items, regardless of the data type or address. The RTDB typically uses registers defined in the range of Modbus addresses, although this is not a strict requirement. However, if the RTDB is connected to a Modbus Slave Channel, it does require Modbus addressing to work properly as a slave (see the Modbus Slave Channel documentation).

Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration.

Click the Edit Table button and add as many rows as necessary to define the desired deadband values for the points in the RTDB.

• Field(Row) – Enter the row number of the field in the RTDB, containing the data point. RTDB row numbers start at 1.
• Offset – Enter the offset into data point address referenced in the field. Offset of 0 refers to the first point number in the RTDB field.
• Count – Enter the number of data points that the deadband limit will be applied to.
• Deadband – Enter the deadband value, which is the amount a value in the RTDB can change before it will be flagged as an RBE. Deadband value is entered as an integer or floating point value, which is handled as an 11-character (max) string. If IEEE floating point format is used, its entry must include a decimal point (such as 11.0).
• Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration. 

Point Count

Type

Data address

Field 1:

100

Boolean

1

Field 2:

100

Boolean

10001

Field 3:

100

UINT16

30001

Field 4:

100

UINT32

40001

Field

Offset

Count

Deadband

Explanation

3

0

4

205

Deadband for 30,001-30,004, 5% of its range

4

2

1

100

Deadband for 40,003

4

3

1

500

Deadband for 40,004

• Data Address – Enter the starting register number to define default values. This should be a register number that is defined as part of the RTDB. 
• Count – Enter a count of registers, beginning with Data Address, that should be initialized to the same value. 
• Init Value – Enter the value to which the register(s) will be initialized on startup. For Boolean registers, enter a '0' or '1' initial value. For floating point registers, enter the initial value in floating point format. 
• Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration.

Click the Edit Table button to define any RTDB tags. 

• Register Address – Enter the RTDB register address in the parent RTDB object. 
• Tag Name – Enter an ASCII tag (up to 32 characters). Do not use the following characters: "|" (pipe), "\" (backslash), and "," (comma). Space characters in the tag are converted to underscores.
• Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration.

Click the Edit Table button to add as many rows as necessary to define the Data Block capability.

• Data Address – Enter the register number of the beginning of each block. This should be a register number that is defined as part of the RTDB.
• Point Count – Enter the number of data points to group together in each block. Ensure the Point Count is not defined larger than the available points in the RTDB field. Data blocking currently supports a contiguous block of data registers using a range of different data types (Boolean, UINT16, UINT32, REAL32), but cannot be used on larger data types (Strings, 64-bit data).
• Comment - Optional column, allowing a descriptive comment to be entered for each row in the table. The Comment field is unused in the configuration.