Ask The Trainer: Mainline Limits and Testing Meters

Video originally published December 2020.

Troubleshooting a Mainline Break That Didn't Shut Down

When a broken mainline doesn't trigger an automatic shutdown, several factors could be preventing the system from responding correctly. The following sections walk through each potential issue and how to verify it's configured properly.

Checking Controller Communication Status

The first thing to verify is whether your controller is online and communicating with BaseManager.

1. Log into BaseManager with your username and password.

2. Navigate to the Maps page.

3. Look at the lower left corner where your controller is listed (for example, "Controller Clock 71" and "Clock 72").

4. Check the color indicator:

• Green means the controller is idle and ready to go—communication is working properly
• Gray means the controller is offline, which could indicate the cell modem is down, WiFi is disconnected, another networking connection has failed, or the controller is not powered up

If the controller shows gray, resolve the communication or power issue before proceeding with other troubleshooting steps.

Verifying Flow Limits and Shutdown Settings

If communication is working properly, the next step is to verify that your flow limits are configured correctly in BaseManager. Before checking limits, confirm that your devices are assigned and set up correctly—specifically that you've assigned your flow meter, assigned your master valve, and entered the correct K value for your flow meter.

1. Navigate to Flow Setup in BaseManager.

2. Open Control Points.

3. Select the control point you want to review and click Edit.

4. Review the following settings:

• Design Flow: Verify this is set to the correct GPM for your system (for example, 120 GPM)
• High Flow Limit: Confirm this is set appropriately above your design flow (for example, 130 GPM)
• Shutdown checkbox: This must be selected for the system to shut down when the high flow limit is exceeded. If this box is not checked, the system will only send an alert but will not shut down. Shutdown is always recommended for high flow limits because they typically indicate catastrophic mainline failure
• Pressure Limits: If applicable, set these and decide whether you want shutdown or just alerts

Confirming Flow Meter K Value and Master Valve Settings

Having the correct K value configured is critical because it translates the pulses from your flow meter into actual GPM readings. An incorrect K value will cause inaccurate flow measurements.

For example, if the system receives a certain number of pulses from a one-inch flow sensor, it might calculate 20 gallons per minute. But those same pulses through a two-inch flow sensor would calculate as 107 gallons per minute. The K value ensures the system interprets the pulses correctly for your specific flow meter size.

Additionally, verify that your master valve is correctly configured as either normally open or normally closed to match your actual valve type.

Configuring User Alert Settings

Even with proper flow limits configured, you won't receive alerts if your user settings aren't set up correctly.

1. Click the menu and navigate to Administration.

2. Click Administration again to open a new tab with a different menu focused on users and user interface settings.

3. Go to User Info to view your user profile.

4. Verify the following settings are configured correctly:

• Enable Text Alert and/or Email Alerts as desired
• Enter your phone number
• Select your cell provider information
• Confirm your email address is correct
• Ensure Disable All Alerts is NOT checked—this is a critical setting that will prevent all alerts from being sent if enabled
• Review the time-of-day settings to confirm when you want to allow alerts (this determines when alerts can be sent to you)

Setting Up Alert Subscriptions

Alert subscriptions determine which alerts you receive for each specific controller.

1. Navigate to Alerts and Report Subscriptions.

2. Open Alert Subscriptions.

3. Review whether alerts are turned on or off for the controller in question.

4. Turn on all alerts initially. It's recommended to start with all alerts enabled because you don't want to miss alerts that may be high priority to you but were categorized as low priority by the engineers who set up the system.

5. If you later find you're receiving too many alerts, you can turn off low-level or low-priority alerts selectively.

Summary Checklist for Mainline Shutdown Issues

If your master valve isn't reacting when it should or you're not receiving alerts about system issues, verify the following:

• Communication is solid between your controller and BaseManager (controller shows green, not gray)
• Flow limits are set correctly in BaseManager and the Shutdown checkbox is selected
• Devices are set up correctly with the proper K value for your flow meter and correct master valve type
• User settings under Administration have correct contact methods (email and/or text), proper timing settings, and Disable All Alerts is unchecked
• Alert subscriptions are enabled for the controller

Understanding the Difference Between a Multimeter and a Milliamp Clamp

Milliamp Clamp Features and Functions

A milliamp clamp is a specialized testing tool that includes a clamp portion and a dial with multiple settings. The dial typically includes:

• Resistance
• Voltage for DC and AC
• AC amps
• Milliamps
• Off

The key distinguishing feature of a milliamp clamp is its ability to measure amperage, which a standard multimeter cannot do.

Multimeter (Volt-Ohm Meter) Features and Functions

A multimeter, also called a volt-ohm meter, typically includes settings for:

• Voltage for AC and DC
• Resistance
• Diode check
• Additional functions if you add extra sensors

The critical limitation of a standard multimeter is that it will not work for amperage checking, which is the primary difference between the two tools.

Using a Milliamp Clamp on Two-Wire Systems

Milliamp clamps are primarily used on two-wire irrigation systems as a non-invasive way to check for overcurrent conditions.

1. Set the meter to AC.

2. Set the meter to AC amps (indicated by an "A" with a wave symbol).

3. Clamp the tool around one side of the two-wire path.

4. Read the amperage draw that is downstream of that point.

This method helps pinpoint overcurrent issues without having to cut into or disconnect wires.

Using a Multimeter to Test Solenoids

Multimeters are commonly used on conventional wire systems to test solenoid resistance.

1. Set the multimeter to resistance (indicated by the omega symbol).

2. Touch the meter leads to the two leads of the solenoid.

3. Read the resistance value. For example, a known good Hunter solenoid typically reads around 24-25 ohms of resistance without the wire path included.

Different manufacturers have different typical resistance values—Rain Bird solenoids read differently than Hunter, and Toro solenoids have their own typical range.

Testing Fuses with a Multimeter

A multimeter can verify whether a fuse is functional, even if it looks intact visually.

1. Set the meter to resistance.

2. Place the leads on either end of the fuse.

3. Check for continuity. A good fuse will show very low resistance, while a burned-out fuse will show infinite resistance or no continuity.

Checking Voltage with a Multimeter

Multimeters can measure both AC and DC voltage, making them useful for various diagnostic tasks.

1. Set the meter to the appropriate voltage type (DC for batteries, AC for line voltage).

2. Place the positive lead on the positive terminal and the negative lead on the negative terminal.

3. Read the voltage. For example, a 9-volt battery reading 8.3 volts is still in good condition.

This function is useful for checking power supplies coming into controllers, verifying battery conditions, or testing voltage in your service vehicle.

Using a Milliamp Clamp for Voltage and Resistance

While milliamp clamps are primarily valued for their amperage-measuring capability, they can also measure voltage and resistance when equipped with an additional set of leads.

1. Plug the additional leads into the milliamp clamp (these typically come with the device).

2. Set the dial to the appropriate function (voltage or resistance).

3. Use the leads just as you would with a standard multimeter to measure voltage or resistance.

This makes the milliamp clamp a three-in-one tool capable of measuring resistance, voltage, and amperage.

Choosing the Right Tool for Your System

The choice between a multimeter and a milliamp clamp depends on your irrigation system type and budget.

For conventional wire systems: A standard multimeter (volt-ohm meter) is sufficient and more affordable. These devices can be purchased at relatively low prices and will handle all the testing needs for conventional systems, including resistance and voltage checks.

For two-wire systems: A milliamp clamp is the best tool to have. While these devices cost significantly more (typically $200-$300), they provide the amperage-checking capability that is essential for troubleshooting two-wire systems. The added benefit is that they can also perform all the functions of a standard multimeter when equipped with the additional leads.

For technicians working with both system types: A milliamp clamp provides the most versatility, covering all testing scenarios across both conventional and two-wire irrigation systems.

Ask The Trainer: Flow Variance & Limit

Video originally published December 2020.

Understanding the Flow Variance Configuration

Flow variance limits allow you to receive notifications when a program runs and there is no flow, such as when someone has shut off the water supply. The configuration involves setting up both control points and main lines with appropriate flow limits and variance percentages. The system monitors expected flow versus actual flow and can alert you or shut down irrigation when the variance exceeds your configured thresholds.

Verifying Control Point Settings

1. Navigate to the Flow Setup tab in BaseManager.

2. Select Control Points from the available options (Water Sources, Control Points, and Main Lines). If you have multiple control points, verify each one or select the specific control point you want to configure.

3. Click Edit on your selected control point to open the configuration settings.

4. Verify the design flow setting matches your control point specifications. The design flow should be accurate for the size of the master valve and flow sensor installed at the control point. For example, a three-inch control point might have a design flow of 120 GPM based on manufacturer charts.

5. Configure the high flow limit by setting it approximately 10-20 percent above your design flow. For a 120 GPM design flow, you might set the high flow limit to 140 GPM. This protects against main line breaks or other issues at the control point level.

6. Enable the Shutdown option for the high flow limit. When this is toggled on, the system will shut down irrigation if flow exceeds 140 GPM. When unchecked, you will receive an alert but the system will continue running. Always start with shutdown enabled, and only toggle to no shutdown if you experience problems.

7. Click Save to preserve your control point settings.

Configuring Basic Flow Variance Limits on Main Lines

1. Return to the Flow Setup tab and select Main Lines.

2. Click Edit on the main line you want to configure. If you have multiple main lines, configure each one individually.

3. Verify that the main line is enabled and that the design flow is set correctly based on your pipe size. This value should come from a pressure loss chart for your specific pipe diameter. For example, a main line might be rated for 120 GPM.

4. Confirm that Manage by Flow is checked if you want the controller to automatically select zone combinations up to your maximum capacity. This feature allows the controller to run a single 40 GPM zone or combine two 60 GPM zones to maximize system capacity up to 120 GPM, optimizing water time and pump efficiency.

5. Enter a percentage in the Flow Variance Limit field. For example, entering 20 means the system will alert if actual flow is 20% more or less than expected flow. If running a single 40 GPM zone, the system would alert if flow exceeds 48 GPM (20% more) or drops below 32 GPM (20% less).

6. Enable Shutdown for the flow variance limit. With this enabled, the system will both alert and shut down when flow variance exceeds your threshold in either direction (high or low).

7. Click Save to apply your basic flow variance settings.

Understanding Basic Flow Variance Limitations

The basic flow variance limit applies the same percentage across all flow rates. This can create challenges when your system runs different combinations of zones with widely varying flow rates. For example, if your system might run a single 20 GPM drip zone at one time and three 40 GPM zones (120 GPM total) at another time, a single percentage doesn't work well for both scenarios. Twenty percent of 120 GPM represents a much larger volume of water than 20% of 20 GPM, which could mean significant damage or waste at higher flow rates while being too restrictive at lower flow rates.

Configuring Advanced Flow Variance

1. In the main line edit screen, clear any value from the basic Flow Variance Limit field and uncheck that option.

2. Locate and check the Advanced Flow Variance checkbox on the right side of the screen. This opens additional configuration fields.

3. Enter flow ranges with corresponding variance percentages. A recommended starting configuration uses progressively tighter tolerances as flow increases:

• 30% variance for low flow ranges (such as 0-40 GPM)
• 20% variance for medium-low flow ranges
• 10% variance for medium-high flow ranges
• 5% variance for high flow ranges (such as 100+ GPM)

4. Configure the same variance percentages for both high flow and low flow sides. Enter 30, 20, 10, and 5 in the corresponding fields on both the high and low flow variance columns.

5. Decide on your shutdown behavior based on your specific needs:

• Alert only on low flow: Check shutdown for high flow but leave low flow set to no shutdown. This configuration alerts you to low flow conditions but continues running zones, ensuring some water reaches your landscape rather than none.
• Shutdown on both high and low flow: Check shutdown for both high and low flow if you have issues with water supply being shut off or want complete protection. This is appropriate when you need to prevent the system from running zones when no water is available.
• Most common configuration: Alert and shut down on high flow (to prevent damage from breaks), but only alert on low flow without shutdown.

6. Click Save to apply your advanced flow variance configuration.

How Advanced Flow Variance Works

Advanced flow variance adjusts tolerance based on the expected flow from the combination of zones currently running. When the controller expects 20 GPM (such as two 10 GPM zones), it applies the 30% variance, giving a wider tolerance window because the absolute volume difference is small. When the controller expects 300 GPM from multiple large zones, it applies only a 5% variance because 30% of 300 GPM would represent a very large leak or break that could cause significant damage.

The system compares actual measured flow against expected flow based on the zones scheduled to run. If a single 40 GPM zone is running and actual flow is 20% outside the expected range, you receive an alert. If three 40 GPM zones are running (120 GPM expected) and flow varies by more than the configured percentage for that flow range, the system responds according to your shutdown settings.

Configuring Alert Settings

After configuring your flow variance limits, verify that your alert settings are properly configured to ensure you receive notifications when flow variance events occur. Alert configuration is accessed through the Admin Menu in BaseManager. Detailed instructions for alert setup are available in a separate video and guide.