QF-35 M8 IP66 Diffuse Photoelectric Switch
A stainless M8 sensor sealed one class beyond the usual: IP66 against water jets, 3 ms response, and a calibrated 35 mm range you can hold it to.
- IP66 per IEC 60529 — survives hose-down and coolant splash
- Stainless-steel M8 x 1.0 barrel, 45 mm overall
- 3 ms or less operate/reset — fast counting
- 35 mm rated range, white-paper calibrated (+/-20%)
- -25 to +55 C; sunlight-tolerant 940 nm IR
Close-Range Sensing Where It Stays Wet
Most micro photoelectric sensors stop at IP65 — fine for dust and drizzle, marginal beside a machining centre's coolant fan-out or under a nightly hose-down. The QF-35 is specified one class up: IP66 per IEC 60529, powerful-water-jet proof, in a corrosion-resistant stainless barrel with a sealed pigtail instead of a connector joint. That is the difference between a sensor you shield and a sensor you simply mount.
Optically it is deliberately honest: a fixed 35 mm rated distance, calibrated on a defined 30 x 30 mm white-paper target with deviation held within 20% — a number you can engineer against rather than a best-case headline. Response is 3 ms or less in both directions, quick enough for high-cycle part counting, and the 940 nm infrared emitter is rated to ignore 3,000 lx incandescent light and 10,000 lx sunlight. Reverse-polarity, short-circuit and mutual-interference protection are built in.
Note: general-purpose presence detection only. The QF-35 is not an IEC 61496-certified safety component and must not be used on its own for personnel protection. IP66 is a general industrial rating, not a food-hygienic certification.
The Calibrated 35 mm Window
Original schematic: the QF-35's fixed sensing window and the conditions it is specified under.
Dimensions and Wiring
M8 x 1.0 thread, 33 mm threaded / 45 mm overall, 13-15 mm sensing face, 2 m PVC cable; NPN and PNP output circuits with built-in overload protection.
Technical Specifications
| Model | QF-35N1 (NPN NO, voltage output) / QF-35P1 (PNP NO) |
|---|---|
| Sensing mode | Diffuse-reflective |
| Rated sensing distance | 35 mm — 30 x 30 mm white-paper target, deviation within 20% |
| Light source | Infrared 940 nm |
| Ambient light tolerance | Incandescent 3,000 lx; sunlight 10,000 lx |
| Supply voltage | DC12-24V +/-10% (ripple p-p within 10%) |
| Current consumption | Under 30 mA |
| Output load | DC24V or below, 80 mA or below, residual voltage under 1 V |
| Response time | Operate / reset: 3 ms or less |
| Protection rating | IP66 (IEC 60529) |
| Protection circuits | Reverse-polarity, output short-circuit, mutual interference |
| Housing / thread | Stainless steel, M8 x 1.0, lock-nut mounting |
| Dimensions | 45 mm overall; 33 mm thread; sensing face 13-15 mm dia. |
| Cable | 2 m PVC 3-core, approx. 3.1 mm OD (brown = V+, blue = 0V, black = output) |
| Temperature | Operating -25 to +55 C; storage -30 to +70 C (no icing/condensation) |
| Humidity | Operating 35-85% RH; storage 35-95% RH |
| Vibration / shock | 10-55 Hz, 1.5 mm amplitude, X/Y/Z 2 h each; 500 m/s2, X/Y/Z 3 times each |
| Certifications | Contact factory (documents on request) |
Selection Table
| Model | Output | Logic | Rated distance | Housing |
|---|---|---|---|---|
| QF-35N1 | NPN (voltage output) | Normally open | 35 mm | M8 stainless, IP66 |
| QF-35P1 | PNP | Normally open | 35 mm | M8 stainless, IP66 |
Normally-closed variants are not in the documented line-up — contact the factory to check current availability. Need a longer range in M8? See the H08 series (up to 200 mm); need a smaller thread, see the H03-H06 micro series.
Typical Applications
Beside Machine-Tool Coolant Spray
IP66 sealing and a stainless barrel let the QF-35 live in the splash zone of CNC and machining stations where IP65 plastic-bodied sensors take on fluid.
Hose-Down Cleaning Points
Wash-down stations on packaging and general industrial lines: the housing withstands powerful water jets per IEC 60529 (general industrial duty, not a hygienic-design certification).
High-Cycle Small-Parts Counting
3 ms operate and reset — noticeably quicker than typical 5 ms micro sensors — keeps counts honest on fast feeders and indexing tables.
Cold Stores and Outdoor-Adjacent Mounts
Rated operation from -25 C up to +55 C (no icing/condensation), plus tolerance of 10,000 lx sunlight, suits chilled plants and bright doorway stations.
Frequently Asked Questions
What makes the QF-35 suitable next to coolant spray or wash-down water?
Three things: an IP66 rating per IEC 60529 (withstands powerful water jets — one class above the IP65 typical of micro photoelectric sensors), a corrosion-resistant stainless-steel M8 barrel, and a sealed 2 m PVC pigtail with no connector joint at the sensor. It is a general industrial rating, not a hygienic-design (IP69K) certification.
How is the 35 mm sensing distance specified?
It is a fixed rated distance calibrated against a 30 x 30 mm white-paper standard target, with deviation within 20% of the rated figure. Darker, smaller or less reflective targets trigger at a shorter working distance, so verify against your actual part.
How fast is the response, and what does that allow?
Operate and reset are each 3 ms or less. At typical feeder speeds that resolves parts passing in quick succession — faster than the 5 ms class of comparable micro diffuse sensors — which is why the QF-35 is often picked for high-cycle counting stations.
Will bright shop lighting or sunlight false-trigger it?
The 940 nm infrared emitter is rated to keep working under incandescent lighting up to 3,000 lx and sunlight up to 10,000 lx, so windows and work lights are normally not a problem.
Can the QF-35 detect transparent objects?
The manufacturer's product literature labels the diffuse sensing mode as capable of detecting transparent objects such as clear film or glass parts. As with all optical detection of transparent targets, validate with your real material before committing the design.
What protection circuits are built in, and how is it wired?
Reverse power-connection protection, output short-circuit protection and mutual-interference protection are built in. Wiring is a 3-core cable: brown = 12-24 VDC supply, blue = 0 V, black = output (NPN for QF-35N1, PNP for QF-35P1); load rating DC24V / 80 mA or below.
Is there an NC version, is this a safety part, and what about samples?
The documented line-up is normally-open only (QF-35N1/QF-35P1) — contact the factory to check current availability of other configurations. It is not an IEC 61496-certified safety component and must not be used alone for personnel protection. Samples for splash-zone trials and current MOQ/lead times: contact the factory.
Specs reviewed by Engineer Cai, Senior Application Engineer. See certificates.
Safety Light Curtain — Customer Cases
Real installations from DAIDISIKE clients. Click any case to view in full. Filter by scenario to quickly find a similar setup.