Setup of Digital Device – Valve – in Accord Builder
Following insertion in a unit, a Valve is configured with settings that will determine its operation and its description in documentation. During insertion, the Valve is given a name and short description. These may be changed at any time.
There are three tabs in the Valve properties configuration section. The general setup is given in the Current Item section. Cross reference, Save and Close buttons are also provided.
Following insertion in a unit each Valve must be configured with settings that will determine its operation and its description in documentation. During insertion the device is given a name and short description. These may be changed at any time.
Each Valve is assigned 1 Output and a number of Feedbacks may be configured. The type required is selectable in the setup area.
Type: This sets the type and number of feedbacks for the valve.
Output: This is the PLC Output address for the valve. This may be Electrical or Bus address
There are following types of Digital Valve Feedbacks:
- No Feedback
- 1 Feedback (Feedback True when Activated)
- 1 Feedback (Feedback True when Deactivated)
- 2 Feedbacks (Feedback 1 True when Activated & Feedback 2 True when Deactivated)
Feedback True when Activated may be thought of as a Normally Open feedback
Feedback True when Deactivated may be thought of as a Normally Closed feedback
Note: Valves are understood to be “Air/Motor to open & Spring to close”. In the case of a valve which is “Air/Motor to open & Air/Motor to close”, this may be catered for as two valves.
Fail to Open: This is the time, in seconds, that the valve is allowed to be Activated without Open feedback status. If this time elapses then the valve is placed in error.
Fail to Close: This is the time, in seconds, that the valve is allowed to have an Activated feedback status while deactivated and at rest. This indicates a feedback signal when not expected e.g. a valve lifting against pressure.
Delay On SP: This is the time, in seconds, that the valve automatic activation will be delayed by the device routine e,g. to avoid pressure issues.
Delay Off SP: This is the time, in seconds, that the valve deactivation will be delayed by the device routine. This feature is used to allow closing of the valve in a controlled manner e.g to avoid line hammer and other pressure issues.
Pulse Cycle Time: This is the overall time of the valve pulsing cycle in seconds.
Pulse Time SP: This is the time, in seconds, that the valve will be pulsed for, during the pulse cycle.
State Text: This text is used to describe the On and Off states of the item in documents and controls. This is a free text field.
Remain Active during Program Hold: This enables the valve to stay Activated if the Program ( sequence) that has activated the valve goes into Hold or Error state. The default without this setting is that the Valve would deactivate.
Conditionally Activate with Pulse: This enables the valve to be pulsed according to a condition in the Program.
Enable Reserved for Automatic: This is to have the valve reserved for automatic only. when this is selected then Manual mode can only be selected with a specific additional override.
Place Unit/Program in Error: This is to enable a valve Error to cause a Program to go into Error state. Some valves are not required to cause programs to go into Error, but in general this box will be ticked.
Manual Only: This option is used if the valve will not be controlled automatically, only controlled from HMI.
Short Description: A short one-line description for the valve.
Interlocks are conditions of devices and instruments that prevent a device from activating. This is to prevent damage to equipment or to material. For example, a pump may not run if a low level in a pipe exists to prevent the pump running dry, or two particular valves may not open together to prevent product mixing.
Interlocks are applicable to HMI manual activation as well as automatic activations.
Clicking on the Edit Interlocks button brings up the Interlocks Tab. There are two types of interlocks allowed. In the first section – the device will be Interlocked unless One item is True, and in the second section – the device will be Interlocked if Any item is True.
Both sections are considered always, – the Device will be interlocked on either section.
In the example the Valve V02 CIP Tank Outlet is interlocked if:
- If V04 is Deactivated and V05 is Deactivated.
2. If LSL01 is Present
To Edit Interlocks click on the Edit Button and the following configuration panel will appear
All of the appropriate items are made available by means of drop down menus.
Types of Interlocking Items:
- A Valve is activated – open
- A Valve is deactivated – closed
- A Valve is in Alarm -error
- A Motor is activated – running
- A Motor is deactivated – stopped
- A Motor is in Alarm -error
- A Digital Output is activated
- A Digital Output is deactivated
- The result of a digital input is High (true)
- The result of a digital input is Low (false)
- An analog input has a High-High Alarm
- An analog input has a High Alarm
- An analog input has a Low Alarm
- An analog input has a Low-Low Alarm
- An analog input does not have a High-High Alarm
- An analog input does not have a High Alarm
- An analog input does not have a Low Alarm
- An analog input does not have a Low-Low Alarm
Once the type of condition is chosen the relevant items which are already configured in the same Unit(s) become available for the choice of interlocking item in the drop-down menu. The required particular interlocking item is chosen from the drop down menu and the Interlock added by clicking “Add Interlock”.
There is a system Option in the Tools menu to make Interlocks Unit based or Plant-wide based. In the case of Interlocks Unit based then the items which are available are those that are in the same unit(s) as the device.
Interlocks may be removed at any time by clicking “Remove Interlock”.
To save the interlocks click the Save button
The configured Activations for the Valve can be seen here, listed with the type of Activation and the program Step in which the Activation occurs. Activations can be removed from this panel by right-clicking on an Activation, to either remove an individual Activation or All Activations.
Card Setup Tab:
A PLC is composed of a CPU and I/O cards on racks, and in some cases communications processors, special function modules and bus based I/O.
Panel, Central Rack, Slot and Channel: These are all text input fields. Once a text is entered for a device or instrument, it then becomes available for other objects in the project. There is no validation on this information; the same combination of information could be entered for more than one device. This would be erroneous as each device must be unique, so care must be exercised in inputting the information. This can be filled in the IO Table in the Menu.
Type: The type of signal associated with the Valve Output is also described in this tab. In this case a 24V DC signal is identified. The information stored in this area is used for documentation and does not comprise object data for PLC control.
The following aspects of the device may be filled in if required:
Symbol: This may be an asset number or any unique identifier which describes the object within the entire company. This could contain references to the plant, the area within the plant, the unit and the digital input name itself.
Part Number: This is the supplier reference for the item.
Type Description: This is a general description of the type of item. If a type is entered, then it becomes available to all other objects of the same type.
Long Description: This describes the object in more detail, if required.
Supplied By: Name of the supplier.
Notes: General Notes on the object. This may contain reference to maintenance manuals, maintenance history or location and type of spare parts.