How to install and commission the LC level controller

Learn how to install and commission an LC level controller and find out how to test the product when it is set up

Thanks to its intuitive display and ability to connect to the Grundfos GO smartphone app, installing and commissioning an LC level controller is a relatively simple process. In this module, we’re going to show you how it is done as well as introduce you to how you can test the product.

First of all, if you need to communicate with external systems, you should install a communication interface module (CIM)."

Simply loosen the screws, remove the front cover and push the module onto the three guide pins into the socket. Once the module is in place,

you can make the electrical connections to the module as they’re described in the instructions supplied with the module. An LC level controller is a compact unit, and as soon the CIM is installed, everything you need will be installed in this box.

This even includes motor protection, which is otherwise typically added externally.

Let’s take a closer look at the electrical installation. We’re going to use a three-phased installation in our example, but you can also use a single-phased installation. First of all, you connect the three phases. They are connected to L1, L2 and L3 as seen here. The pump is connected directly to the relay. Next, you connect your pump – or pumps, if you have two – to the PTC terminals. PTC stands for positive temperature coefficient. These little resistors measure the temperature of the windings in the pump.

When they exceed a certain temperature, the PTC switches signal to the controller to stop the pump. While the pump is stopped, it cools down.

Once it is at a suitable temperature, it starts running again. While PTC measures temperature, it cannot measure the level of moisture inside the pump.

Fortunately, a moisture sensor can do that. The moisture sensor is in the same wire as the PTC switches, so if the pump doesn’t restart after the temperature has been cooled down, it is because moist has entered the pump, in which case, it will need to be fixed.

A new input has been designed in the LC level controllers to help detect both overheat and moisture in one signal. Once you turn on your pump, the display will start to blink. This is where you need to decide which sensors will measure the level.

There are two different ways of doing this. One way is by placing a pressure sensor in the water inside the pit or well. The higher the pressure, the higher the level of water. Another more traditional way is by using floaters. Once you’ve selected your preferred sensor, you enter the nominal current and select either a single- or three-phase installation.

Next, you’ll go through several level settings. First up, you have to set the dry-running level. Next, you have to select at which level the pumps should stop. Then, you select how high the level should be before pump 1 and pump 2 start, respectively. Finally, you select a level that you deem as being “critically high”. Once you’ve set all this up, the pump is running. But that was just a quick setup by means of the user display on the LC controller. Let’s take a look at the broad range of possibilities that Grundfos GO brings. First of all, you need to download the app. It’s available on both AppStore and GooglePlay.

Once you’ve downloaded the app and connected it to your pump via Bluetooth,

you will be given an overview of how they’re performing. You can also get status reports on how much electricity they have used, how many hours they’ve run and much more.

But it is in the ‘Settings’ menu that Grundfos GO truly stands out. This is where you can get the most out of your LC controller. For instance, you can adjust the various start/stop levels directly from the app.

But you can even adjust the configuration of certain inputs and outputs. Simply select whether the configurable input/output is set to digital input, temperature, digital output and so on.

Grundfos GO is the only place from which you can decide what you would like the sensor to measure, providing you a much more intuitive and easy-to-understand overview than the display unit on the controller. Earlier, we mentioned the temperature and moisture sensors. In Grundfos GO, you can select how long the expected cool down time is for the pump. That way, you get a clear understanding of whether it is the temperature sensor or moisture sensor that has an issue. Once you have installed and commissioned your LC controller, it is time for a test run. In the final part of the module, we’re going to briefly show you how to do this in emptying applications. First of all, you need to fill the pit with water and ensure that the pump starts automatically at the defined level. To test the dry-running function, simply start the pump manually and wait while the pit is emptied.

If the control unit indicates an alarm and stops the pump when the set level is reached, the dry-running function is working fine.

The high-level function can be tested by stopping the pump manually and continuing to fill the pit with water. And when the control unit indicates an alarm, the defined level is reached. That covers the installation and commissioning process of the LC level controllers. We hope that this will help you next time you’re working with an LC level controller.

Course overview

Modules: 3
Completion time
Completion time: 20 minutes
Difficulty level
Difficulty level: Intermediate