NEW ARRIVAL: Siemens QVE1901 Mechanical Flow Switch Now Available
Model Description
We are pleased to announce the immediate availability of the Siemens QVE1901 mechanical flow switch, a robust paddle-type sensor engineered to monitor the operation of hydraulic circuits using liquids or non-aggressive gases. Designed for pipe diameters DN 20 … DN 200 (¾" … 8"), the switch is mounted directly in-line through a G ½" female thread and requires no external power supply. A field-adjustable stainless-steel paddle (40 … 111 mm selectable length) detects flow velocities from 0.8 m³/h up to 30 m³/h and actuates a potential-free change-over contact. The compact brass body (120 × 38 × 92 mm, 0.31 kg) fits easily inside HVAC risers, heat-pump skids, chiller headers and industrial coolant lines, providing a simple, maintenance-free “flow proven” signal to BMS or safety interlocks .
Key Features
QVE1901 delivers reliable switching up to 1 A @ 230 V AC (26 VA) or 1 A @ 48 V DC (20 W), covering most relay and PLC input loads. PN 25 pressure rating (25 bar) and –20 … +110 °C fluid temperature range suit chilled-water, glycol, hot-water and low-pressure steam circuits. IP65 protection and a –20 … +80 °C ambient rating allow rooftop or plant-room installation without additional enclosures. A manual NO/NC selector on the micro-switch gives engineers flexibility for “flow present” or “flow failure” signalling, while the snap-action mechanism responds within 2 … 15 s depending on paddle length. CE, cULus and RoHS approvals validate global projects, and the device is completely maintenance-free—no batteries, electronics or calibration required .
Related Models in the QVE Family
Siemens offers complementary variants for different duties. QVE1902 provides the same hydraulic spec but with a gold-flashed micro-switch for low-current (< 100 mA) circuits; QVE1900 covers smaller pipes DN 15 … 50 with a shortened paddle. For electronic flow sensing, QVE2100.010 (4 … 20 mA) and QVE3100.010 (pulse output) retrofit into the same G ½" boss when analogue data is required. All models share identical mounting threads, IP65 housings and brass wetted parts, enabling one-size drillings and unified wiring diagrams across HVAC and process plants .
Our Competitive Advantages
As a dedicated Industrial Automation trader, we provide exceptional procurement flexibility and customer-centric service solutions. Our adaptable payment structures accommodate wire transfer arrangements and customized credit facilities for approved partners, removing financial barriers to urgent maintenance requirements. We maintain significant strategic inventory in regional distribution hubs, enabling delivery within 5-7 business days to most industrial centers worldwide. Our extensive sourcing network spans premium European and Asian sensor distribution channels, ensuring authentic Telemecanique component traceability without geographic restrictions. This multi-channel approach guarantees availability during global supply chain disruptions. Our application engineers provide sensor selection consultation, detection distance calculation, and integration support, assisting with control logic configuration and wiring optimization. Through direct manufacturer partnerships and streamlined logistics, we deliver genuine Telemecanique inductive sensors with accelerated fulfillment cycles and competitive pricing structures.
For immediate quotations or technical consultation, please contact our dedicated sales team.
About Us
We are a focused industrial-automation components trader committed to delivering authentic Siemens flow-control solutions with speed, flexibility and technical expertise.