GF Signet 2537 Paddlewheel Flowmeter

Next-generation Rotor-X style paddlewheel flowmeter for DN15…DN200 (½…8 in.) with low-flow capability to 0.1 m/s and configurable S3L, 4–20 mA, or multi-function outputs.

Key advantages

Low-flow down to 0.1 m/s — operating range 0.1…6 m/s (0.3…20 ft/s).
Multiple outputs — digital S3L, 4–20 mA, or multi-function pulse / flow-switch styles by code.
Same fittings as 515 / 2536 — installs into DN15…DN200 with GF Signet fittings.
On-site configuration — built-in user interface; low power and high-resolution options.

Typical applications

Process flow monitoring, pump protection, filtration, RO, demineralization, fume scrubbers, and cooling towers.
Chemical and water lines using PP or PVDF sensor bodies.
Multi-sensor setups with GF type 9950-XX hosts (up to six sensors per published feature).

Selection guide

Pipe size / velocity — DN15…DN200 (½…8 in.); 0.1…6 m/s.
Accuracy — Linearity ±1% of max. range @ 25 °C; repeatability ±0.5% of max. range @ 25 °C.
Output — Digital S3L; 4–20 mA; multi-function with dry-contact or solid-state relay options.
Supply — By output: multi-function ~6–24 VDC / 24 VDC nominal; S3L 5.0–6.5 VDC; 4–20 mA 12–32 VDC (per datasheet).
Wetted materials — Glass-filled PP or PVDF body; rotor PVDF/ETFE options; shaft Ti / Hastelloy-C / PVDF / ceramic / Ta / SS; O-rings FKM (std), EPDM/FFKM optional.
Process connection — GF Signet 515/2536-compatible fittings.
Update rate — System response ~100 ms nominal.

Common mistakes

Expecting magmeter-style zero-moving-part performance in dirty slurry — paddlewheels need relatively clean liquid and proper velocity.
Ordering 4–20 mA without checking loop supply (12–32 VDC class) vs S3L host power.
Mismatching rotor/shaft materials to chemistry.
Assuming DN > 200 coverage — published pipe range stops at DN200 (8 in.).
Flow instruments · Flow buying guide

When to RFQ / what to tell us

Pipe size (DN15…DN200), fluid, and working velocity / flow.
Output: S3L / 4–20 mA / multi-function; relay type if needed.
Body (PP/PVDF), rotor/shaft, O-ring.
Temperature/pressure, host instrument, quantity, ship-to country.

Request a Quote · Get selection help

Specs

Spec	Value
SKU	20202
Brand	Georg Fischer / GF Signet
Model	2537
Product type	paddlewheel flowmeter
Measuring range	Operating velocity 0.1 to 6 m/s (0.3 to 20 ft/s); pipe sizes DN15 to DN200 (½ to 8 in.)
Accuracy	Linearity ±1% of max. range @ 25 °C; repeatability ±0.5% of max. range @ 25 °C
Output signal	Digital S3L; 4–20 mA; multi-function pulse / flow switch (by code)
Supply voltage	Per output code: S3L 5.0–6.5 VDC; 4–20 mA 12–32 VDC; multi-function 6–24 / 24 VDC class
Process connection	GF Signet fittings (same family as types 515 / 2536)
Wetted materials	Glass-filled PP or PVDF body; PVDF/ETFE rotor options; Ti/Hastelloy-C/PVDF/ceramic/Ta/SS shaft; FKM/EPDM/FFKM O-rings
Notes	Values aligned with GF datasheet 3-2537.099 Rev N 06/2026-A.

Documents

GF Signet 2537 datasheet (PDF)

FAQ

Q: How low can the 2537 measure? A: Published operating range starts at 0.1 m/s (0.3 ft/s). Confirm your minimum velocity before RFQ.

Q: Can it replace a 515 mechanically? A: It uses the same Signet fitting family as types 515 and 2536 for DN15…DN200. Confirm output/electronics code for electrical drop-in.

Q: What should I send for a quote? A: Pipe size, fluid, velocity/flow, output, materials, T/P, host, quantity. Compatible with systems using GF Signet 2537 if you need a drop-in check — we do not claim authorized-dealer status.