Back To Top
Fisher™ SS-263 Volume Booster
The SS-263 volume booster is used exclusively in Fisher Optimized Digital Valve (ODV) packages.
It amplifies the output signal from the FIELDVUE™ digital valve controller to increase the stroking speed of pneumatic actuators. It can deliver high-volume output for fast stroking speeds when responding to large input signal changes or smooth, stable, low-volume output when responding to small input signal changes. This allows stable, accurate throttling control which is often necessary during the startup or commissioning of process control equipment.

Components of a Fisher Compressor Anti-Surge Control Valve

Play Video
Fisher™ SS-263 Volume Booster


Port Diameters
Supply port: 19 mm (0.75 inch)
Exhaust Port: 19 mm (0.75 inch)
Input Signal
Positioner output
Maximum Input Signal Pressure
10.3 bar (150 psig)
Input to Output Pressure Ratio
Fixed at 1 to 1
Supply Pressure Ranges
Maximum pressure must not exceed 10.3 bar (150 psig)
Operating Temperature
-40 to 71 C (-40 to 160 F)
Maximum Flow Coefficients
Supply: 9.5 Cv
Exhaust 9.5 Cv
C1: 35
Xt: 0.77
Input signal: 1/4 NPT
Supply: 1 NPT
Output: 1 or 1-1/4 NPT
Hazardous Area Classification
Complies with the requirements of ATEX Group II Category 2 Gas and Dust
Declaration of SEP
Fisher Controls International LLC declares this product to be in compliance with Article 3 paragraph 3 of the Pressure Equipment Directive (PED) 97 / 23 /EC. It was designed and manufactured in accordance with Sound Engineering Practice (SEP) and cannot
Approximate Weight
Aluminum: 3.6 kg (8 lbs)
Stainless Steel: 10.8 kg (24 lbs)
Other Configurations
Contact your local Emerson business partner or sales office to learn about additional specifications or options for this product.


  • Fast Response: The SS-263 delivers high-volume output for fast stroking speeds when responding to large input signal changes and low-volume output when responding to small input changes.
  • High capacity: Flow capacities of roughly three times higher than the 2625 booster result in the need for fewer fittings, tubing, and units.
  • Noise Attenuation: Exhaust is passed through specially-designed passages to reduce the amountof ambient noise that is generated.
  • Adjustable Response: The integral bypass restriction allows the booster to be easily and readily tuned to operate under small or large input signal changes.
  • Auxiliary Supply Connections: Supply air is readily available through two 1/4 NPT connections that are built into both sides of the unit for use with a Fisher 377 trip valve or other accessory.
  • 3 in 1 Connection: This special connection can provide any of the following connections, if needed: 1/4 NPT diagnostic connection for easy testing, 1/4 NPT actuator bypass assembly connection foruse on an actuator with a handwheel, and 3/4 NPT connection
  • Soft-Seated Construction: Soft seated exhaust and supply valves provide for bubble tight shutoff toreduce unnecessary air consumption and ensure fail mode upon loss of plant air.
  • Robust Mounting: Flanged-style actuator mounting provides ease of maintenance, simplifiedtubing, compactness, and high vibration resistance.