The typical modular terminal block has two "wired" connection points, one for each side of the terminal block. These types of terminal blocks are usually represented in a project with one schematic symbol, one panel layout symbol, and one wiring diagram or graphical plan symbol each.
A terminal strip is a group of terminal blocks with the same device ID. Terminal blocks in the strip can have unique or duplicate terminal numbers.
Wire lists, wiring diagrams, and graphical plans are all alternate ways of showing connection information found in the schematics. Users can use varying combinations of these outputs or none at all.
With multi-tier terminal blocks, also known as multi-level or double- or triple-deck terminal blocks, each tier of a terminal block is often best represented by separate schematic symbol. This presents some challenges:
Other devices, such as relays, are also represented by multiple schematic symbols. The separate symbols are grouped as a single device by means of a family. Attributes and part numbers can then be assigned to the group as a whole. And with a family, the bill of materials will list the correct quantities despite the multiple symbols. With a part number assigned, a symbol can be placed for the device in other modes such as Panel Layout Mode or Wiring Diagram Mode. These same principles can be applied to multi-tier terminal blocks.
This document will set up the supporting data for a three-tier feed-through terminal block as an example. Each tier of this example terminal block carries a separate potential and has two wiring points. The techniques described here can be adapted to other styles of multi-tier terminal blocks and to fit different company standards.
This document assumes the user has familiarity with basic functions of the drawing platform and functions such as symbol creation.
Create a new family using the Catalog Manager or by selecting Create Family.
Enter 3-TIER_TB for the Family Name.
Set the Family Type to terminal/pin-plug.
Add three roles, each with the TB symbol specified for the Symbol Name. Each role will represent a tier of the terminal block. The TB symbol can be found in the JIC-3 or ANSI-IEEE catalog.
Modify the connection point texts so that the default I and E connection points are instead TOP_I and TOP_E for the first role (top tier), MID_I and MID_E for the second role (middle tier), and BOT_I and BOT_E for the third role (bottom tier). Note: Do not add any Hidden Text values. Do not modify the J connection point texts.
Do not enter a value for Number. This will allow a terminal number to be specified when the symbols are placed.
The wiring diagram symbol created in this example will be used for both wiring diagrams and graphical plans. Typically users generate either wiring diagrams or graphical plans, but since the symbol type for both is Wiring Diagram, one symbol will serve both purposes for the example.
Select Create Symbol.
In the Select Existing Symbol step, select New Symbol (From Scratch), click Next.
In the Specify Symbol Type step, select Wiring Diagram for the Symbol Type.
In the Import Connection Points step, select Import Connection Points From a Family.
Click Select Family and select the 3-TIER_TB family created in the previous section.
Draw a box 1.25" x 1.5" as shown. Divide the box into thirds to represent the tiers.
In the Specify Device ID step, set the Suppress Display of ID check box.
Click the Place button under Tag Mnemonic then click near the box on the drawing. Exact location does not matter since the device ID will be hidden when the symbol is used.
Click the Place button under the Terminal Number area and place a terminal number attribute in each "tier" of the box drawn. In this example the top segment of the box will represent the top tier. Since the top tier is the first role defined in the family, the attribute for "Seq No." 1 should be placed in the top segment. Similarly, the attribute for sequence number 2 should be placed in the middle segment and the attribute for sequence number 3 in the bottom segment.
For clarity, use Place Text to place TOP, MID, and BOT text elements on the symbol in the appropriate segment. This is not required by the software.
In the Place Connection Points step, remove the values from the Visible Text column, at least for the I and E connection points. Note that all five connection points from each of the three TB symbols for a total of 15 have been imported. Only the wired points (connection points with I or E in the CP text) will be placed on this symbol.
Set Text Align to Middle Right and place the connection point with hidden text of TOP_I on the left side of the top segment, and the connection point text to the left of the connection point.
Set Text Align to Middle Left and place the TOP_E connection point on the right side of the top segment and the connection point text to the right.
Repeat steps 12 and 13 for the MID and BOT connection points in the middle and bottom segments respectively.
In the Specify Position step, place the insertion point in the middle of the top line of the box.
In the Save Symbol step, enter W-3TIERTB for the symbol name and select the desired catalog.
Select No on the "Yes to continue placing, No to renumber all placed connection points" prompt. This will delete the unplaced null and J connection points.
In order to insert a wiring diagram or generate a graphical terminal plan, a part number must be assigned to a terminal block device. The part number record specifies the family and the symbols to use for the device in the different modes and for graphical plans.
Add a part number to the parts database to use for this example:
Select Parts Database Manager.
Click the Add Record [+] button.
Enter 3TIER for the Part_Number field.
Enter 3-TIER_TB for Device_Family, or browse to avoid typing errors.
Enter TB for Schematic_Symbol.
Enter W-3TIERTB for Wire_Diagram_Symbol.
Enter W-3TIERTB for Graphical_Plan_Symbol.
The wiring diagram, wire list, and graphical plan shown in later sections of this document are based on the schematic shown below. In the schematic, wires 100, 101, and 102 are wired to the top, middle, and bottom tiers respectively of terminal block 1 on strip TB1. Wires 103, 104, and 105 are wired to the top, middle, and bottom tiers respectively of terminal block 2 on strip TB1.
This circuit is not necessarily a realistic application, for multi-tier terminal blocks or otherwise.
To create similar circuits:
Create a new project and schematic page.
Place a TB symbol and the Device Properties dialog will appear.
Assign TB1 for the Device Tag.
Leave Installation and Location blank in this example for simplicity.
Assign the 3TIER part number. This should also assign the 3-TIER_TB family to the device, and the Device Usage Chart dialog will then appear. Select the first role in the family (the top tier in this example) and click OK. Note that the CP Text changes to include "TOP_I" and "TOP_E".
Enter 1 for the Terminal No. and click OK.
Place another TB symbol, and again specify TB1 for the device tag.
The Device Usage Chart should appear. Select the second role of the family.
Select Yes at the "Do you want to duplicate the terminal number?" prompt.
Repeat steps 7 - 10 for the third role of the family.
Place another set of three TB symbols representing a second 3-tier terminal block in strip TB1 using the methods in the previous steps. Since all the roles in the family assigned in a previous step are used, an Engineering Design Consideration will appear when the next symbol is placed. Click the Append button, assign the 3TIER part number, and enter "2" for the terminal number.
Draw wires from other devices to the terminal symbols so that the wiring diagram, wire list, and graphical plan will be populated with more data.
Although there are six terminal block symbols on the schematic, they represent only two terminal blocks. If a quantified bill of materials report was run at this time, it would show a quantity of "2" for part number 3TIER.
With the schematic page created in the previous section open, select Run Reports. Preview a Wire List report. For the schematic shown in this document, the resulting report is shown below.
The first line in the report shows that a wire with wire number 100 runs from connection point 4 on LS101 to the top tier of terminal 1 in strip TB1.
Switch to Wiring Diagram Mode.
Select Insert Symbol By Device ID and choose Terminals/Plugs in the Filter Devices area, then click Search.
Highlight the row for TB1 terminal 1 and click the Place Symbol(s) button. Click on the drawing to place they symbol.
Select Update Wiring Diagram and select the page where the wiring diagram symbol was placed.
For the schematic shown in this document, the resulting wiring diagram symbol is shown below.
The default display settings of [Device Tag]:[Connection Point][Wire Number] for wiring diagram symbols as seen above can be customized in Options > Project Options > Wiring Diagram Settings.
Select Run Graphical Plan. Choose the ANSI-IEEE Standard Graphical Plan 2 (V) template for the Graphical Plan Template for strip TB1, and click the Place Strip(s) button. Below is the graphical plan generated for the schematic shown in this document.
It is possible to assign different terminal numbers to different tiers of the same terminal block when placing the schematic symbols.
If potential is shared between tiers of a terminal block due to internal connections in the terminal block, the connection points that share potential would be given the same value for Group Name on the Edit Potential Group dialog. This enables potential to be carried across different symbols. Access the Edit Potential Group dialog by clicking the Edit Group button on the New/Modify Family dialog.
This document describes a modular terminal strip consisting of individual terminal blocks. For a non-modular terminal strip that is purchased as a unit, the terminal family could represent all the connection points in the strip and terminal numbers could be assigned in the family.