Understanding Follow, Latch and Pulse modes
Follow is the default operating mode for all Davicom relays. When configured in the Follow mode, a relay will mirror the state of the input it is controlled by.
Latch is an operating mode that will maintain the relay in its new state for an indefinite period of time, until a Release command (manual or automatic) is received.
Pulse is an operating mode that will pulse the relay for a period of time (default duration is 1 second). Pulse duration can be set from 0.1 second to 999 seconds.
Physical relays (xRyy)
This section will guide you in setting physical relay parameters, in order to match the control requirements of the equipment they are connected to. Each relay output is set individually according to its use and function.
To configure relay outputs, click the Unit Configuration icon (
) then on the Outputs tab and select Physical Relays.
Example from image above: Physical relay 1R08 is connected to a generator, and is controlled only by Virtual Logic Gate 1V06. Since 1V06 is controlling 1R08 in the follow mode, the relay was set for the Follow/Latch mode (Any would also have worked).
The upper portion of the Physical Relays Configuration dialog box allows you to set the following parameters:
Relay Number: Select from the dropdown list the number of the specific relay output you wish to configure. Physical relays are all identified by the R letter, followed by one or two digits (up to 32 depending on your Davicom model).
Note: Relay Numbers will begin by a digit (1 to 4) to identify a specific Davicom unit when several DV-208/216 units are networked together (SuperMAC). Otherwise it must begin with the digit 1.
Enable: Check this box to enable the physical relay. When disabled, the relay will not operate. Default setting is enabled.
Default Description when Energized: Long Unicode description used to describe the relay when it’s energized. To facilitate identification of the relay, the description should include the external equipment to which the relay is connected. (Maximum 30 alphanumerical Unicode characters). Refer to this article for more details.
Note: For very short pulse duration relays, this description may not have time to be displayed on DavLink I/O Indicators nor I/O State LEDs. Refer to Sections 11.3.2.7 and 11.3.2.8 of the Reference Manual for more details on indicators and LEDs.
Alternate Description when Energized: Short ASCII description used to describe the relay when it’s energized. To facilitate identification of the relay, the description should include the external equipment to which the relay is connected. (Maximum 18 alphanumerical ASCII characters).
Note: For very short pulse duration relays, this description may not have time to be displayed on DavLink I/O Indicators nor I/O State LEDs.
Default Description when Released: Long Unicode description used to describe the relay when it’s released. To facilitate identification of the relay, the description should include the external equipment to which the relay is connected. (Maximum 30 alphanumerical Unicode characters).
Alternate Description when Released: Short ASCII description used to describe the relay when it’s released. To facilitate identification of the relay, the description should include the external equipment to which the relay is connected. (Maximum 18 alphanumerical ASCII characters).
The lower portion of the Physical Relays Outputs configuration dialog box screen is divided into four tabs. To configure Vocal Descriptions, refer to this article. For Modbus information, please refer to the Davicom Expansion Module (MEXM) manual and other Support documentation on the Davicom website. To configure automatic Actions, set the following parameters:
Operating Mode: Select one of three possibilities. If all inputs controlling the selected physical relay are to use Follow mode, you can select Follow/Latch. If all inputs controlling the selected physical relay are in Pulse mode (letter P after the relay identifier), you can select Pulse Only. For these two operating modes, you can also prevent users from manually controlling the relay by selecting Automatic Only. Note that you will be unable to configure a relay under one of these two modes if the relay is already controlled by an input using a different mode. Also, by selecting one of these two modes, you will not be able to later configure inputs with the selected relay in a different mode. Choosing Any (default setting), allows inputs to control the relay in any mode. The Result field may show relay operation codes used in previous DavLink versions, and is given for reference purposes only.
Controlled By: Up to 8 inputs controlling the selected relay will be automatically displayed. The xZyyy entry format is used. This field is read only. Note: If more than 8 inputs control the relay, all will be taken into account, but only the first 8 inputs to have been configured will be displayed.
Pulse Width: Enter the pulse duration in seconds. Minimum 0.1 second, maximum 999 seconds. Default value is 1 second.
System Log: This check box enables logging all the relay activities in the system log.
Custom Log: Davicom units can provide one custom log in addition to the extensive system log. This allows Davicom users to focus-in on desired information. Check this box if you want to record events related to the selected physical relay in the custom log. By default this box is not checked. This setting also enables periodic data logging (refer to Section 4.7.3.1 on page 138 of the Reference Manual for more details).
Virtual relays (xOyyy)
This section will guide you in setting virtual relay parameters, in order to qualify conditional actions without using physical relays. Each virtual relay is set individually according to its use and function.
To configure virtual relays, click the Unit Configuration icon () then on the Outputs tab and select Virtual Relays.
Virtual Relays are configured exactly the same way as Physical Relays (refer to Section 2 Physical relays (xRyy)). The only differences are: the identifier uses a different letter and the number of relays is greater. These are described below:
Virtual Relay Number: Select from the dropdown list the number of the specific Virtual Relay you wish to configure. Virtual Relays are all identified by the O letter, followed by one, two or three digits (up to 128 depending on your Davicom model).
Note: Virtual Relay Numbers will begin by a digit (1 to 4) to identify a specific Davicom when several DV-208/216 units are networked together (SuperMAC). Otherwise it must begin with the digit 1.
For an example of a virtual relay being used as a remote switch to manually trigger a generator test normally activated by a timer, refer to Figure 38 on page 76 of the Reference Manual. This setting allows you to manually Force-On/Off the virtual relay in order to start/end the test without affecting the periodic automatic test settings.
