LF42 series pressure switch is used in water supply pressure protection of water inlet. This series water pressure switch include two models LF42H(high-pressure protection) and LF42L(low pressure
protection).
LF42H is the high pressure protection switch model. If the pressure of the pressure vessel transferred reaches the setting value while the vessel is full flled with water, the switch will cut off the circuit to make the pump stop. So the pump will not be damaged.
LF42L is the low pressure protection switch. If the pressure of water inlet lower than set value, RO will not work and keep dewatering, then the switch will cut off the circuit to make the pump stop. It can prevent the booster pump still working without water which may lead to damage to the circuit. If the pressure of the water inlet returns to the lowest set volume, the pump will work again.
Transmitter
| Model | LF42H | LF42L |
| Medium | water | water |
| Pressure set range | cut off pressure:2.5bar+0.5bar | cut in pressure:≤0.1bar |
| cut in pressure: 1.5bar+0.5bar | cut off pressure: 20.2bar | |
| Proof pressure | 1 8bar | 1 8bar |
| Durability | > 40,000 times | > 40,000 times |
| Working temperature | 5-45C | 5-45°C |
| Switch type | Microswitch, nomal close | Microswitch, nomal open |
| Electrical rating | Voltage:250V AC Current:16A | Voltage:250V AC Current:16A |
| Terminal | 4.8*0.8 mm blade | 4.8*0.8mm blade |
| Connector | 6mm quick connector | 6mm quick connector |

Robust and compact structure.
BPA free food level plactic made.
Precise pressure control and durable working span.
LF40H water pressure switch for pumps is a device that can automatically control the electric connection of the pump, which can prevent dry-running damage to the pump.
Product Inquiry
15 Sep 2026
LFP1140T WASHDOWN PUMP: FULLY EMPOWERING FLOOR SCRUBBERS AND MEDICAL CLEANING APPLICATIONS08 Sep 2026
LEFOO Showcases Pumps and Sensors at the 139th Canton Fair24 Aug 2026
Demand Delivery Pump vs. Booster Pump: What Is the Difference?23 Aug 2026
How to Choose a High Flow Peristaltic Pump for Industrial Fluid Transfer
English
français
Deutsch
Español
italiano
русский
português
العربية
Türkçe
Zulu 