VMRK

Functional description

The measuring unit is fitted with an effective pressure sensor for measuring the volume flow rate.

The effective pressure is either measured and evaluated manually, or transformed into an electric signal by a pressure transducer.

Plastic (PPs) circular volume flow rate measuring unit for the measurement of volume flow rates in air conditioning systems, available in 6 nominal sizes.

For the manual volume flow rate measuring or for the permanent monitoring of the actual value signal.

Ready-to-commission unit which consists of the casing with an averaging differential pressure sensor.

Spigot, suitable for ducts according to DIN 8077.

Casing air leakage to EN 15727, class C.

Special features

• Measurement accuracy ± 5 % even with unfavourable upstream conditions
• Effective pressure range: approx. 5 – 250 Pa
• Low differential pressure of only about  15 – 24 % of the measured effective pressure

Materials and surfaces

• Casing made of flame-resistant polypropylene (PPs)
• Differential pressure sensor made of polypropylene (PP)

Technical data

• Nominal sizes: 125 – 400 mm
• Volume flow rate range: 25 to 1680 l/s or 90 to 6048 m³/h
• Effective pressure range: approx. 5 – 250 Pa
• Measuring unit differential pressure (pressure loss): 15 – 24 % of the measured effective pressure
• Operating temperature: 10 to 50 °C

Attachments

Volume flow rate measurement with static differential pressure transducer emitting an actual value signal for integration into the central BMS.

• Supply voltage 24 V AC/DC
• Signal voltages 0 – 10 V DC or 2 – 10 V DC
• EASYLAB: Integration using either 0 – 10 V DC signals or expansion modules (LonWorks, BACnet MS/TP, Modbus RTU)

Sizing data

• V _______________________ [m³/h]

This specification text describes the general properties of the product. Texts for variants can be generated with our Easy Product Finder design programme.

VMRK, VARYCONTROL differential pressure transducers

VMRK, LABCONTROL differential pressure transducers

Anbauteile: VARYCONTROL Regelkomponenten

① TROX, ② TROX/Belimo, ③ TROX/Gruner, ④ Sauter, ⑤ Siemens

☒ Bestellschlüsseldetail, V Volumenstrom, Δp Differenzdruck

Principal dimensions

ØD [mm]

VAV terminal units made of stainless steel: Outer diameter of the spigot

VAV terminal units made of plastic: Inside diameter of the connecting spigot

ØD₁ [mm]

Pitch circle diameter of flanges

ØD₂ [mm]

Outer diameter of flanges

ØD₄ [mm]

Inside diameter of the screw holes of flanges

L [mm]

Length of unit including connecting spigot

L₁ [mm]

Length of casing or acoustic cladding

B [mm]

Duct width

B₁ [mm]

Screw hole pitch of flange (horizontal)

B₂ [mm]

Outside dimension of flange (width)

B₃ [mm]

Width of device

H [mm]

Duct height

H₁ [mm]

Screw hole pitch of flange (vertical)

H₂ [mm]

Outside dimension of flange (height)

H₃ [mm]

Unit height

n [ ]

Number of flange screw holes

T [mm]

Flange thickness

m [kg]

Weight including attachments for the automatic differential pressure measurement

Nomenclature

V_nom [m³/h] and [l/s]

Nominal volume flow rate (100 %)

V_min [m³/h] and [l/s]

Volume flow rate

ΔV [± %]

Volume flow rate accuracy

K value  [m³/h] and [l/s]

Unit-related constant for air density 1.2 kg/m³

Δp_w [Pa]

Effective pressure

Δp_st [%]

Static differential pressure in relation to the measured effective pressure