Valve Has No Precipitation Rate or Too High Precipitation Rate (When Running a Valve Schedule)
Issue
A valve in your drawing has either no precipitation rate or too high of a precipitation rate.
Causes
A valve's precipitation rate may be incorrect for several possible reasons:
- One or more of the heads connected to the valve may have a Z elevation.
- The layer name in Preferences for the coverage layer, LI-COVR-SPRY, may have been changed, or someone may have gone into the Block Editor and moved the coverage symbol to a different layer.
- The coverage radius block within the head may be too big or small.
If you're thinking the precipitation rate for an Area for Drip Emitters zone is incorrect, keep in mind that the total area used in the calculation comes from the shrub size. Although we generally calculate precipitation rates using the area method, the area used in the calculation for Areas for Drip Emitters comes from the area of the shrub rather than the total area of the hatch.
Solution
Step 1: Check for a Z Elevation
Select a head in the problematic station.
Then right-click and select the Select Similar option from the menu.
All heads connected to the problematic valve will be selected.
Open the Properties panel by typing Prop in the Command line and pressing Enter.
Important: Size the lateral pipe connected to the valve again. Then size the mainline again.
Now run a Valve Schedule and check the entry for the problematic valve in the PRECIP column.
The valve should now have the correct precipitation rate.
You can now test the valve's precip rate by running a Valve Schedule. Still getting an incorrect precip rate? Move on to Step 2.
Step 2: Confirm That the Coverage Radius Layer Name is the Same in the General Preferences and the Head Blocks
Open the General Preferences.
In the Layers area, scroll down and confirm that you see a layer named LI-COVR-SPRY. This is the default name for the layer that contains the coverage radius for each spray head.
Don't see the correct layer name in the list? Someone in your office may have changed it. You'll need to do some investigation into what that new layer is now named. If necessary (and if you can locate the layer in the list), follow our steps to change the layer name back to the correct name.
As a safeguard, we include a description in the Edit Layer dialog box for each layer that includes the default name of that layer. To open this dialog box, select the layer in the General Preferences and click Edit.
In the example to the left, the name of the layer has been changed to LI-COVR-spray, but its description includes the default layer name and color. You can use this information as a guide in locating the correct layer, as well as changing its name back to the correct one.
If the layer name is correct, or you've changed the layer name back to the correct one, verify that the name of the coverage radius layer in the block matches the layer name in the Preferences.
Select a head within the problematic station. Type BE in the Command line and press Enter to open the Block Editor.
You'll be checking the layer name of the coverage radius, which is a layer within the head block. Hence, the need to open the Block Editor for a head.
The Edit Block Definition dialog box will open. Confirm that you've selected the correct head block. In this example, we've selected a bubbler.
Click OK.
The Block Editor for the selected head will open.
Select the coverage radius.
Type Prop in the Command line to open the Properties panel.
Check the Layer entry for the coverage radius, and confirm that it's on the layer LI-COVR-SPRY.
If it's on a different layer, use the menu to move it to the correct layer: LI-COVR-SPRY. Each head's coverage radius should now move automatically to the correct layer.
Close the Block Editor and save your changes.
Important: Size the lateral pipe connected to the valve again. Then size the mainline again.
You can now test the valve's precip rate by running a Valve Schedule. Still getting an incorrect precip rate for the valve? Your coverage radius may be the wrong size within your emitter blocks. Move on to Step 3.
Step 3: Change the Size of the Coverage Radius
If the coverage block is too big or small, you can edit the coverage radius layer in the block editor and make that circle a bit bigger or smaller.
Select a head within the problematic station. At this point, you can also look at the size of the coverage radius of each head in that station.
In the example to the right, both bubblers have an excessively small coverage radius, which just appears as a dot.
Type BE in the Command line and press Enter to open the Block Editor.
The Edit Block Definition dialog box will open. Confirm that you've selected the correct head block. In this example, we've selected a bubbler.
Click OK.
The block editor for the selected head will open.
In this example, the coverage radius is excessively small. When selected, it's not even visible outside the blue selection box. As a result, we'll need to make it bigger.
With the coverage radius selected within the head block, type Prop and press Enter to open the Properties panel.
Check the Scale X and Scale Y entries. If the coverage radius is excessively small, you'll need to increase these entries. If it's excessively large, you'll need to decrease them.
In our example, we'll increase the Scale entry to 1500.
You'll likely need to play around with the Scale X and Scale Y values, trying different numbers until the coverage radius is the size you need. Just make sure that the Scale X and Scale Y values match.
In our example, a scale of 1500 did the trick; the coverage radius is now the necessary size.
You can test the size of the coverage circle by typing Distance in the Command line and pressing Enter. You can then measure the diameter of the circle.
Once the coverage radius is the size you want, close the Block Editor and save your changes.
You may need to repeat these steps for other heads whose coverage radius is excessively small. Or you can simply:
1. Delete all heads with the wrong size coverage.
2. Type PRG in the Command line and press Enter.
3. Place the heads again.
The coverage radius for the head(s) you edited in the Block Editor should now have the correct size in your drawing.
Important: Size the laterals again. Then size the mainline again.
You can now test the valve's precip rate by running a Valve Schedule.
Contact
- Land F/X
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