The FZ30 3-valve manifold is installed between the impulse lines and a differential pressure or pressure transmitter to isolate the process, equalise pressure between the two chambers and vent pressure for checking, calibrating or replacing the transmitter without shutting down the system. The body is SUS304 or SUS316 stainless steel with 1/2-14NPT, M20×1.5 or weld-tube connections and instrument-side centres of 54 – 57.6 mm to fit most popular DP transmitters.
Equipment Industrial Solution Co., Ltd (ISE) supplies the FZ30 together with DP transmitters and helps you choose the right connection and centre distance for your existing instruments.
Functions of a 3-valve manifold
- High-pressure (HP) and low-pressure (LP) block valves isolate the transmitter from the process.
- Centre equalising valve connects HP and LP chambers for zero DP – used to check and adjust transmitter zero.
- Protects the sensor diaphragm from one-sided overpressure during start-up and shutdown.
- Allows transmitter removal and maintenance without shutting down the boiler or pipeline.
FZ30 manifold specifications
| Parameter | Value |
|---|---|
| Type | 3-valve manifold |
| Material | SUS304, SUS316 stainless steel |
| Process-side connection | 1/2-14NPT (female); M20×1.5 (male); M20×1.5 (male) with weld impulse tube; on request |
| Instrument-side centre distance | 54 mm; 55.2 mm; 55.6 mm; 57.2 mm; 57.6 mm; on request |
| Process-side centre distance | 33 mm (standard); on request |
How to operate a 3-valve manifold
Putting the transmitter into service:
- Check that all valves are closed.
- Open the equalising (centre) valve.
- Slowly open the HP block valve – pressure enters both chambers evenly, avoiding one-sided overpressure.
- Close the equalising valve.
- Open the LP block valve. The transmitter starts measuring.
Zero check: close the LP valve, open the equalising valve – DP is zero, check for 4 mA. Then close the equalising valve and reopen the LP valve.
Removing the transmitter: close HP and LP valves, open the equalising valve and vent pressure at the transmitter before removal.
For steam or hazardous media always follow plant safety procedures and never leave the equalising valve open while both block valves are open.
Applications
- With the CST305X-DPT differential pressure transmitter for orifice/venturi flow and DP level measurement.
- CST-DPLM boiler drum level system: balance container + manifold + transmitter.
- Pressure drop across filters, pumps and heat exchangers in power, chemical, water and oil & gas plants.
FAQ
3-valve vs 5-valve manifold?
A 3-valve manifold has two block valves and one equalising valve. A 5-valve manifold adds two vent/test valves for in-situ calibration and venting gas or draining condensate – common for gas and steam flow. Contact ISE if you need a 5-valve version.
How do I choose the centre distance?
The instrument-side centre distance must match the DP transmitter flange (54 mm is most common). Send us your transmitter model and we will select the right manifold.
Related products
Where to buy the FZ30 3-valve manifold?
EQUIPMENT INDUSTRIAL SOLUTION CO., LTD (ISE) – Ho Chi Minh City, Vietnam – supplies genuine the FZ30 3-valve manifold with technical consulting, fast quotation and on-site commissioning support across Vietnam and Southeast Asia.
Contact us: Sales +84 909 617 185 – Technical +84 979 117 185 – Email: [email protected]
