• Fast Response—Booster delivers the volume needed for rapid actuator stroking when large input changes suddenly occur.
• Adjustable Response—Integral bypass restriction tunes the booster response so that smooth actuator motion follows the slow signal changes.
• Efficient Operation—Soft seats provide tight shutoff to reduce unnecessary air consumption and eliminate saturation of positioner relays.
• Maintains Accuracy—Booster permits high actuator stroking speeds upon demand without degrading the positioner steady-state accuracy.

Supply Pressure Ranges

When used in conjunction with a positioner or other pneumatic accessory, always pipe the positioner and volume booster with one common supply through a 64 or 95H regulator (see figure 3). A high-capacity filter, such as the 262C, should be installed in the supply line to the regulator. Supply pressure also must not exceed the maximum pressure rating of the actuator. Constructions are available in two maximum supply ranges.
When Normally Used With Diaphragm Actuators: Up to 2.8 bar (40 psig)
When Normally Used With Piston Actuators: Up to 10.3 bar (150 psig)

Input Signal Pressure

Positioner output

Maximum Input Signal Pressure

10.3 bar (150 psig)

Fixed Input-to-Output Pressure Ratio

1 to 1

Nominal Deadband

Percent of Positioner Output Span(1):
2.4 mm (0.094 inch) exhaust port: 2%
9.5 mm (0.375 inch) exhaust port: 3.5%
12.7 mm (0.5 inch) exhaust port: 5%

Construction Materials

Body: Aluminum
Seat Ring: Brass
Diaphragms 2625: Nitrile/nylon
2625NS: EPDM/meta-aramid
Upper and Lower Valves:
2625: Nitrile-CSM rubber/aluminum/stainless steel
2625NS: EPDM/aluminum/stainless steel
O-Rings:
2625N: Nitrile
2625NS: EPDM
Connectors for Diagnostic Testing: ■Stainless steel or ■brass

Operative Temperature Limits(2)

2625: -40 to 71°C (-40 to 160°F)
2625NS: -40 to 93°C (-40 to 200°F)

Connections

Input Signal: 1/4 NPT
Supply and Output: 3/4 NPT

Port Diameters(3)

Supply Port: ■9.5 mm (0.375 inch) or
■ 12.7 mm (0.5 inch)
Exhaust Port: ■2.4 mm (0.945 inch),
■9.5 mm (0.375 inch) or ■12.7 mm (0.5 inch)

Maximum Flow Coefficients

See table 1

Hazardous Area Classification

Complies with the requirements of ATEX Group II Category 2 Gas and Dust

Approximate Weight

2.3 kg (5 lb)

Note
Use a clean, dry, oil-free air supply with instruments containing EPDM components. EPDM is subject to degradation when exposed to petroleum-base lubricants.

Keep in mind that many actuators require larger casing or cylinder connections to take full advantage of the booster's ability to deliver its high-volume
output. Dimensions are shown in figure 4. Ensure that the supply pressure is connected to correspond with the flow arrow on the booster.

Note
Critical stroke speed time example: Valve to stroke in both directions in 4 seconds or less.

Non-critical stroke speed time example: Valve to stroke in approximately 4 seconds in both directions.

4. Nuclear service, if applicable. Consult factory for ordering assistance.

Note
Neither Emerson, Emerson Process Management, nor any of their affiliated entities assumes responsibility for the selection, use, or maintenance of any product. Responsibility for the selection, use, and maintenance of any product remains with the purchaser and end-user.