SIKA VVX25 DN 25 vortex flow meter with 4…20 mA output, G 1¼ (VVXB2SGBAL003526)

SIKA VVX25 is a vortex flow meter for measuring water and aqueous solutions in the range 7…150 l/min. It has a PPS GF40 plastic body, a fully enclosed piezoceramic sensing element, and no moving parts. This configuration (VVXB2SGBAL003526) provides a 4…20 mA current signal corresponding to a flow of 0…150 l/min, as well as an additional Push-Pull pulse output 200 imp/l. The process connection is an external thread G 1¼ (ISO 228) with O-rings.

Features, advantages and benefits

• Vortex measurement method (Kármán vortex street) → the frequency of the sensor being crossed by vortices is proportional to flow, and the flow meter has no moving parts and no mechanical wear. → stable water flow measurement without a rotor that can wear out or become clogged.
• Fully enclosed piezoceramic element (no direct contact with the medium) → the vortex-sensing sensor is insulated from the water, making it resistant to contamination. → greater measurement reliability in installations where small particles may appear in the circulation.
• Analog output 4…20 mA (0…150 l/min) → the current signal is a standard in automation, where 4 mA corresponds to 0 l/min and 20 mA corresponds to 150 l/min. → easy connection to PLC controllers, regulators and BMS systems without additional converters.
• Parallel Push-Pull frequency output 200 imp/l → one pulse corresponds to 5 ml of liquid, and at a flow rate of 150 l/min the frequency is 500 Hz. → the ability to count volume (e.g. with an impulse counter) alongside the current flow reading from the analog output.
• Measurement independent of medium conductivity → the vortex principle does not require a conductive liquid. → the sensor works with water and aqueous solutions of different conductivity without the need to match it to the water quality.
• Low flow obstruction → low pressure drop across the flow meter (pressure drop chart in the manufacturer's datasheet). → lower load on the circulating pump and lower energy consumption.
• High long-term stability, no zero drift → the readings do not shift over time. → repeatable measurement throughout the service life without frequent zero checks.
• PPS GF40 body, ETFE sensor, EPDM O-rings → the materials in contact with the medium are glass-fiber reinforced PPS (GF40), ETFE and EPDM. → durable construction for operation with water at temperatures from -20 to 90 °C (without freezing).
• 100% final robot test, 3-point calibration, serial number → each sensor is checked on water, and its parameters are recorded and assigned to the serial number. → documented, traceable measurement quality.
• M12 x 1 connector (5-pin), IP65 and IP67 protection rating → a standard industrial connector, and the stated protection rating applies to the sensor with the cable socket fitted. → quick installation and replacement and protection of the connection against moisture and dust.

Technical data

Accuracy stated for water at 20…30 °C and defined straight runs before and after the sensor (see the manufacturer's instructions). Greater deviations may occur with higher-viscosity media. FS = full-scale range.

Application

SIKA VVX25 flow meter is used to measure water flow at low to medium flow rates, including in heating technology. It is suitable for heating and cooling systems where the medium is water or an aqueous solution at a temperature of -20…90 °C (without freezing), as well as in heat pump systems. Thanks to the 4…20 mA output, it can be easily integrated into automation systems, and the pulse output allows additional counting of the volumetric flow.

Frequently asked questions (FAQ)

How is VVXB2SGBAL003526 different from VVXB2SGBVL003526?

Only in the type of analog output. Version VVXB2SGBAL003526 has a 4…20 mA current output, while VVXB2SGBVL003526 has a 0…10 V voltage output. The range 7…150 l/min, G 1¼ connection, Push-Pull 200 imp/l output and 12…24 V DC supply are the same.

What is the flow measurement range?

The measuring range is 7…150 l/min (420…9000 l/h). The analog output span covers 0…150 l/min, with accuracy specified for the 7…150 l/min range.

How do I convert the 4…20 mA output to flow?

Flow in l/min = (I − 4 mA) / 16 mA × 150. For example, 12 mA corresponds to a flow of 75 l/min, and 20 mA to 150 l/min.

What supply voltage is required?

For this version with a 4…20 mA output, the supply voltage is 12…24 V DC (±10 %).

Can I use both the 4…20 mA output and the pulse output at the same time?

Yes. In this configuration, the analog signal is on pin 2, and the pulse Push-Pull output (200 imp/l) is on pin 4. The pulse output allows the volume to be counted, where one pulse equals 5 ml.

For which media is the flow meter intended?

For water and aqueous solutions at temperatures from -20…90 °C (without freezing). With higher-viscosity media, measurement deviations may occur.

Does this version also measure temperature?

No. In the VVXB2SGBAL003526 configuration there is no temperature signal output, and pin 5 has no signal.

Which cable should be selected for the VVX25 flow meter?

The M12 x 1 (5-pin) connector is compatible with a cable fitted with a five-pin M12 x 1 socket. We recommend the XVVX482 cable with a length of 2 m. Lengths of 1 m, 1.5 m, 3 m, 5 m and 10 m are also available.