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Premier Control Technologies Fluid Solutions

Variable area

These Variable-area piston meters use a spring‑loaded, sharp‑edged orifice and magnetically coupled follower to display flow. With no electronics required and unrestricted mounting (horizontal, vertical, inverted), they’re ideal for panels, skids and plant utilities - across liquids and gases.

Product range

Our Products

B Series – Basic inline liquid VA meter

The core, all‑metal indicator for water and oils, available in aluminium, brass or stainless bodies with NPT/SAE/BSPP ports. Typical accuracy ±2.0% FS, repeatability ±1% FS, and pressure capability up to 6,000 psi (410 bar) on stainless builds. Commonly used for pump performance checks and hydraulic/cooling circuits.

M & N Series – Variable‑area flow alarm/switch

A VA meter with single or dual SPDT switches for on/off alarming (coolant/lube assurance, interlocks). Field‑adjustable set‑points; available for liquids or gases, with line sizes ¼″–2″ and working pressures up to 414 bar (model‑dependent).

T Series – Variable‑area flow transmitter

Adds proportional outputs (4–20 mA, 0–5 V, 1–5 V, or pulse) to the VA platform for PLC/SCADA integration while retaining a local scale—handy for batching, data logging or remote trending. Pressures to 414 bar, in aluminium/brass/SS with NPT/SAE/BSPP.

H Series – High‑temperature VA meter

Built for thermal fluids and hot oil service. H‑Series to 400°F (204°C) with the same rugged construction and unrestricted mounting.

P Series – Phosphate‑ester (Skydrol®) VA meter

Factory‑scaled for phosphate‑ester aviation fluids (very low SG), with materials/ seals selected for compatibility. Pressures to 6,000 psi (410 bar) and the usual VA convenience. Common on aircraft hydraulic power units and test rigs.

G Series – Pneumatic (air/gas) VA meter

Calibrated for air/compressed gases (e.g., SCFM scales) and used on compressor outputs, tool drops and general pneumatics. Accuracy is typically ±2.5% FS in the middle third of scale (±4% FS at the ends). Pressures up to 600–1,000 psi depending on body.

C Series – Case‑drain VA monitor

A cost‑effective indicator tailored to pump case‑drain oversight (predictive maintenance). Accuracy typically ±5% FS, repeatability ±1% FS, with max ~1,000 psi (69 bar) and compact aluminium body.

Bi‑Directional Series – Measures both flow directions

All the benefits of the Basic meter, engineered to indicate when flow reverses (e.g., pump testing, reversing circuits). Pressure capability up to 6,000 psi on stainless builds.

ClearView – Transparent‑body VA meter

An economical, compact indicator that also lets you visually inspect the fluid for aeration/contamination. Polycarbonate (water) or polysulfone (oil) bodies with brass/Ryton® ports; max ~325psi (22.4bar) and up to 200°F (93°C). Great for municipal water, pump output verification and case‑drain observation.

Key features & benefits (mapped to the series)

  • Unrestricted mounting: install horizontal, vertical or inverted—no straight run piping needed. (B, M&N, T, H, P, G, C, Bi, ClearView)
  • Rugged, weather tight construction for wash down or outdoor panels; all metal pressure vessels on core series. (B, M&N, T, H, P, G, C, Bi)
  • High pressure capability: up to 6,000 psi (410 bar) in stainless builds on core liquid series and 3500–6000 psi options across Bi Directional/Phosphate Ester. (B, Bi, P)
  • Hot service options to 400°F/204°C (H) and 600°F/315°C (J) for thermal oils. (H/J)
  • Switching and control:
    • M&N add single/dual SPDT alarm contacts for low flow protection.
    • T adds 4–20 mA/voltage/pulse outputs for PLCs—keep the local scale.
  • Media specific builds: P Series pre scaled for phosphate esters (Skydrol® class), with compatible seals; G Series scaled for air/gas (SCFM). (P, G)
  • Maintenance insight: C Series highlights rising case drain flow (wear), while ClearView shows clarity/entrainment at a glance. (C, ClearView)

How the mechanism works

A spring holds a tapered metering pin against a sharp edged orifice. Increasing flow pushes the internal magnet/piston against the spring to a new position, which the external follower magnet tracks on a graduated scale. It’s simple, robust and field readable.

Common FAQs on variable area flow meters

Basic liquid models are typically ±2.0% of full scale (±1% repeatability). Case drain versions are ±5% FS.
No. VA piston meters from this range support horizontal, vertical or inverted mounting, with no straight run requirement.
Stainless models on the core series are rated to 6,000psi (410bar), aluminium/brass typically 3,500psi (240bar); case drain up to 1,000psi; ClearView up to 325psi. Always check the specific build.
Yes — G Series pneumatic meters are calibrated in SCFM for air/compressed gases and carry the same rugged build.
Choose the Bi Directional series, which indicates both directions without re plumbing.
Yes — P Series is factory scaled for phosphate ester media and offered in compatible materials/seals.
Use M & N flow alarm models with single or dual SPDT contacts; set points are field adjustable.
Select the T Series transmitter with 4–20 mA / voltage / pulse output, retaining a local scale for walk by checks.
Yes — H Series (to 400°F) cover elevated temperatures; confirm seals and body materials for your fluid.
PCT actively procures and holds these families (e.g., B4S and CV C variants) with regular orders logged—ask us for current lead time/stock on the exact range/porting you need.

Help and advice

A member of our team will be happy to assist with any questions you may have.

Ask the team