Main properties for a Honeywell Universal Modbus channel
The Main tab defines the basic properties for a Honeywell Universal Modbus channel The communications port used by the server to connect to a controller. Channels are one slot, point, or screw terminal of an I/O device for a single I/O value, and are defined using the Quick Builder tool..
For information about how to create a channel, see "Building controllers and channels" in the Quick Builder User’s Guide.
| Property | Description |
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Name |
The unique name of the channel. A maximum of 10 alphanumeric characters (no spaces or double quotes). Note: In Station Experion's main operator interface. Station presents information using a series of displays. See also: display. displays, underscore characters ( _ ) appear as spaces. |
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Description |
(Optional) A description of the channel. A maximum of 132 alphanumeric characters, including spaces. |
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The Tag Name A unique identifier given to a point or an asset. Compare: item name. See also: asset, point. of the Asset to be associated with the controller Also known as remote terminal unit, RTU. A generic term for a device that is used to control and monitor one or more processes in field equipment. The most common control and monitoring device in an access control and security system is an access control panel. Other devices include security monitoring panels, elevator controllers, and fire monitoring devices. Controllers include programmable logic controllers (PLCs), loop controllers, bar code readers, and scientific analyzers. See also: C200 controller, control processor, CPM, hybrid controller, network node controller, PLC.. |
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The communications alarm marginal limit at which the channel is declared to be marginal. When this limit is reached, a high priority alarm is generated. To change the priority of the alarm system wide, see the topic titled "Configuring system alarm priorities" in the A channel barometer monitors the total number of requests and the number of times the controller did not respond or response was incorrect. The barometer increments by two or more, depending on the error, and decrements for each good call. To calculate an acceptable marginal alarm limit, use the formula In ISA-S88.01 terms, a category of recipe information that includes process inputs, process parameters, and process outputs. In Honeywell terms, the recommended implementation of a formula is through using Phase block formula and report parameters.: Square root of the number of controllers on the channel × Marginal Alarm Limit defined on those controllers (Normally, you specify the same value for all controllers on a channel). For example, if there are 9 controllers on the channel and their Marginal Alarm Limit is set to 25, the value would be 3 (which is the square root of 9) × 25 = 75. |
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Fail Alarm Limit |
The communications alarm fail limit at which the channel is declared to have failed. When this barometer limit is reached, an urgent alarm is generated. To change the priority of the alarm system wide, see the topic titled "Configuring system alarm priorities" in the Set this to double the value specified for the channel Marginal Alarm Limit. |
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Write Delay |
If the channel is on a serial port, the length of time (in milliseconds) that the server The computer on which the Experion database software and server utilities run. See also: Experion server TPS. waits before writing to For redundant HC900 Hybrid controller. networks, the suggested Write Delay is 0. |
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Connect Timeout |
The time (in seconds) the server waits to connect to Use the default value For redundant HC900 networks, the suggested Connect Timeout is 1. |
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Read Timeout |
The time (in seconds) that the server waits for a reply from Use the default value For redundant HC900 networks, the suggested Read Timeout is 1. |
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Item Type |
The type of channel specified when this item was created. |
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Last Modified |
The date and time the channel properties were modified. |
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Last Downloaded |
The date and time the channel was last downloaded to the server. |
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Item Number |
The unique item number currently assigned to this channel, in the format CHN You can change the Item Number if you need to match your current server database configuration. The number must be between |
Channel write delay settings
Serial devices using the RS-485 protocol require a minimum period during which no communications occur. Different devices have different requirements. You should configure the write delay to be the largest value required by any device on your RS-485 network. See the following table for requirements of individual devices.
Where a delay is specified in number of characters, convert the value to milliseconds using this formula:
Time(ms) = (1,000 × characters)/baud
Write delay should be rounded up to the nearest whole number.
For example, 3.5 chars at 9600 baud = (1,000 × 3.5)/9600 = 3.6 ms (round to 4 ms)
| UMC800 | DPR100, DPR180, DPR250 | DR4300 | DR4500 | UDC3300, UDC2300 |
|---|---|---|---|---|
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3.5 Chars |
3.5 Chars |
V 4: 20 ms V 5 or later: 3.5 Chars + 2 ms |
V 57 and 58: 20 ms V 59 or later: 3.5 Chars + 2 ms |
20 ms |