The GEMU C30 Hydra-Gauge is equipped with a PFA transmitter and a pressure gauge. The body is made from PFA and can be directly integrated into the pipe system by commom flare unions. A PFA double diaphragm prevents contamination of the working medium. Only the PFA body and the PFA diaphragm are wetted parts. The pressure is transmitted by a monitor liquid (50 % Dl water and 50% IPA (isopropyl alcohol)). The pressure gauge complies with EN 837-1.

  • C30 is especially suitable for pressure measurement of ultra high purity chemicals
  • All wetted parts are made from High Purity PFA
  • Pressure transmission by double diaphragm technology
  • Pressure gauge can be rotated through 360°
  • Not suitable for applications with strong vibrations, pulsing process pressure or pressure peaks; provide for suitable pulsation dampers and throttling sections, if necessary
  • Minimal deadleg
  • The proven GEMU CleanStar® technology is the basis of the transmitter
  • Working medium hermetically isolated from the gauge by a double diaphragm
  • Proven long term reliability
  • Pressure gauge can be positioned through 360° enabling individual user options


Type C30
Nominal Size 1" DN 20 1/2" DN 10 1/4" DN 4 1/4" NPT DN 4 3/4" DN 15 3/8" DN 6
Mounting Variant Dead-End In-Line
Connection Flare connection with PFA union nut Flare connection with PVDF union nut NPT female thread NPT male thread
Body Material PFA
Diaphragm Material PFA
Units Double scale bar / psi Double scale kPa / bar Double scale psi / bar
Measuring Range 0...100 psi, 0...600 kPa, 0...6.0 bar 0...30 psi, 0...250 kPa, 0...2.5 bar 0...60 psi, 0...400 kPa, 0...4.0 bar -30 inHg...15 psi, -100...150 kPa, -1...1.5 bar -30 inHg...30 psi, -100...300 kPa, -1...3.0 bar -30 inHg...60 psi, -100...500 kPa, -1...5.0 bar
Connection Form Back, center mount Bottom
Sight Glass Acrylic glass Instrument flat glass
Switching Contacts Electronic contact PNP, 1. Break / 2. Make contact Electronic contact PNP, 1. Make / 2. Break contact Inductive contact, 1. Break / 2. Make contact Inductive contact, 1. Make / 2. Break contact Magnetic spring contact, 1. Break / 2. Make contact Magnetic spring contact, 1. Make / 2. Break contact Without
Fill Fluid of Transmitter DI water Isopropyl alcohol (IPA) / DI water 50:50
Transmitter Version High Purity White


Version of Transmitter Diaphragm Double diaphragm system for overpressure ranges Single diaphragm for ± pressure ranges
Material of Wetted Parts PFA
Flow Medium Suitable for any inert or corrosive gases or liquids, especially high purity media which do not corrode the respective body and diaphragm materials.
Flow Direction Optional
Working Range Constant: 3/4 of full scale range Momentary: full scale range Variable: 2/3 of full scale range
Influence of Temperature 0.5 % of measuring range (scale end value) per 10°C temperature change (reference temperature 20°C).

Pressure Gauge

Accuracy ±1.6 % of measuring range or scale end value
Nominal Size 063 mm
Material of Measuring System CrNi steel 1.4571
Gauge Material CrNi steel with Teflon coating

Switching Contacts

Switching Functions1 Break Contact: Opens as pressure decreases Make Contact: Closes as pressure increases
Inductive Contact Non-touching switch, no wear, high reliability, Ex approval, additional switching unit required
Magnetic Spring Contact Open contacts, can switch power directly
Electronic Contact Inductive contact with integrated switching amplifier, non-touching switch, high reliability, for direct connection to a PLC or piloting relays
  • 1 The switching function is irrelevant when piloting a PLC.