Introduction
The Grundfos LiqTec is designed to protect pumps from dry run conditions and excessive liquid temperatures. It offers robust construction and reliable operation.
Table of Contents
- 1. Description
- 2. LiqTec Sensor Mounting
- 3. Electrical Connection
- 4. Sensor and LiqTec Calibration
- 5. Functions
- 6. Sensor and LiqTec Calibration Process
- 7. Additional Information
- 8. Waste Disposal
1. Description
The LiqTec unit provides protection for pumps by:
- Protecting the pump from dry run conditions.
- Protecting the pump from excessive liquid temperatures (up to 130 °C ± 5 °C).
- Monitoring motor temperature when a PTC sensor is connected to the motor.
- Featuring a fault-tolerant design. In case of a fault in the sensor, sensor cable, electronic module, or power supply, the pump is immediately shut down.
2. LiqTec Sensor Mounting
The LiqTec can be mounted on a DIN rail and installed in a control cabinet. Refer to page 4 for mounting illustrations.
3. Electrical Connection
Examples of electrical wiring are shown on page 5.
4. Sensor and LiqTec Calibration
Refer to the procedure described on the following page.
5. Functions
Diagram of LiqTec Unit and Connections:
Illustration shows the LiqTec unit with numbered connection terminals and indicator lights.
- 1. Dry Run Sensor Connection: Dry run sensor product number: 96556427.
- 2. External Start Connection: For external start signal.
- 3. Motor PTC Indicator: A green light indicates normal operation or that PTC protection is not used (contacts are short-circuited). A red light indicates excessive motor temperature, triggering the signaling relay.
- 4. PTC Sensor Connection: For connecting a PTC sensor compliant with DIN 44082 standard. If the PTC sensor is not used, the contacts must be short-circuited.
- 5. Sensor Indicator Light: A red light indicates a damaged sensor or cable. Triggers the signaling relay.
- 6. Dry Run Monitoring Function Disable: Pressing this button disables the dry run monitoring function. The red light will flash. PTC monitoring continues to function. Press the Restart button to re-enable the dry run monitoring function.
- 7. High Liquid Temperature Indicator Light: A red light indicates that the liquid temperature is too high (130 °C ± 5 °C). Triggers the signaling relay.
- 8. Power Supply: 200-240 V, 50/60 Hz.
- 9. Dry Run Indicator Light: A green light indicates normal operation (liquid is present in the pump). A red light signals dry run (no liquid in the pump). Triggers the signaling relay.
- 10. Alarm/Operation Relay Output: Zero-potential changeover contact. Maximum contact load: 250 V, 1 A, AC (inductive load).
- 11. Auto/Man: Switch between automatic and manual restart. The default setting is Man (manual). Can be switched with a small screwdriver. When set to Auto, the alarm is automatically interrupted after 10-20 seconds of detecting liquid.
- 12. Restart: Press this button to restart the pump if necessary. This button does not affect PTC monitoring.
6. Sensor and LiqTec Calibration Process
| Step | Action | Result |
|---|---|---|
| 1 | Verify that the sensor is properly connected to the LiqTec (see page 5). | |
| 2 | Before inserting the sensor into the pump, immerse it in standing water. Any container with water can be used. Note: It is important that the water is standing, as flowing water cooling the sensor will lead to inaccurate calibration. | |
| 3 | Press and hold buttons 6 and 12 for approximately 20 seconds. | All red indicator lights (except 7) will start flashing. |
| 4 | When green indicator lights 3 and 9 start to light up continuously, release buttons 6 and 12. | Calibration is complete. |
7. Additional Information
Information related to IEC 60730-1:
- Software class A.
- Degree of pollution 2.
- Type 1.
LiqTec has been cURus approved according to UL 508.
| Maximum pressure: | 40 bar |
| Maximum liquid temperature: | +130 °C ± 5 °C |
| Maximum ambient temperature: | +55 °C |
| Power consumption: | 5 Watt |
| Enclosure class: | IPX0 |
| Maximum cable length: | 20 meters |
| Standard cable: | 5 meters |
| Extension cable: | 15 meters |
| Product number: | 96443676 |
Wiring Diagram
Illustration shows a schematic wiring diagram connecting the LiqTec unit to power supply (L1, L2, L3, N), a sensor, an external restart input, a PTC sensor, and a motor (M) via a contactor (K1).
Key Connections:
- Power input: L1, L2, L3, N (200-240 V).
- Sensor input: Connects to the dry run sensor.
- External restart: Input for an external restart signal.
- PTC input: For connecting a motor PTC sensor.
- Output: Controls a contactor (K1) which in turn controls the motor (M).
8. Waste Disposal
This product and its components must be disposed of in accordance with environmental regulations:
- Utilize the services of a public or private waste collection company.
- If this is not possible, contact Grundfos or an authorized Grundfos service workshop.
Subject to change.
Declaration of Conformity
The Grundfos LiqTec unit complies with relevant EC/EU directives. Declarations of conformity are available in multiple languages, including English and Lithuanian, and can be found in the product documentation. For the latest online version and full documentation, visit the Grundfos Product Center at: http://net.grundfos.com/qr/i/96562445
