Emerson Fisher 2625, Fisher 2625NS Instruction Manual

Instruction Manual

D100348X012

2625 and 2625NS Volume Booster

Fisherr 2625 and 2625NS Volume Boosters

January 2015

Contents

Introduction 1.................................

Scope of Manual 1..............................

Description 1..................................

Specifications 2................................

Educational Services 3...........................

Installation 4..................................

Mounting 4..................................

Pressure Connections 5........................

Diagnostic Connections 6......................

Supply Pressure 6.............................

Exhaust Ports 7...............................

Operating Information 7.........................

Principle of Operation 7.........................

Maintenance 8.................................

Diaphragm Assembly Replacement 8.............

Valve Assembly Replacement 9..................

Installation of Diagnostic Connections 10.........

Parts Ordering 11...............................

Parts Kits 11...................................

Parts List 11...................................

Introduction

Figure 1. Fisher 2625 Volume Booster

W4727-1

Scope of Manual

This instruction manual provides installation, operation, maintenance, and parts information for Fisher 2625 and
2625NS volume boosters (figure 1). Refer to separate instruction manuals for information regarding the valve body,
actuator, and other accessories.

Do not install, operate, or maintain a 2625 or 2625NS volume booster without being fully trained and qualified in
valve, actuator, and accessory installation, operation, and maintenance. To avoid personal injury or property damage,

it is important to carefully read, understand, and follow all of the contents of this manual, including all safety cautions
and warnings. If you have any questions regarding these instructions contact your Emerson Process Management sales

office before proceeding.

Description

The 2625 is certified for use in Safety Instrumented System (SIS) applications. Certification is by EXIDA Consulting LLC,
a global provider of functional safety and control system security. SIS certification is identified on the product by the
EXIDA logo on the 2625 nameplate.

The 2625 and 2625NS volume boosters are used in conjunction with a positioner on a throttling control valve to
increase stroking speed. The booster has a fixed deadband (controlled by the seat‐to‐seat dimension of the supply and

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2625 and 2625NS Volume Booster

January 2015

exhaust plugs) which is factory set during assembly and testing. In addition, the booster incorporates soft‐seat
construction and an integral bypass restriction to eliminate positioner saturation problems that can occur with volume
boosters that do not have these features. Adjustment of the integral bypass restriction is necessary for system
stability. This adjustment does not affect the deadband of the booster, but does permit the control valve to respond to
small input signal changes from the positioner without sacrificing steady‐state accuracy.

It also allows the booster to deliver high‐volume output for fast stroking when large, rapid input signal changes occur.

The volume booster is used to improve stroking speed. If precision valve control is required, the use of a positioner is
recommended. If you use the volume booster only with an actuator, for on‐off control, the integral bypass restriction
on the volume booster must be closed (turned fully clockwise).

To facilitate diagnostic testing, you can install connectors and piping with each 2625 and 2625NS volume booster.

The 2625NS volume booster is designed for nuclear power applications. The 2625NS construction includes materials
that provide superior performance at elevated temperature and radiation levels.

The O‐rings in the 2625NS are EPDM (ethylene propylene) and the diaphragms are EPDM/meta‐aramid. EPDM
demonstrates superior temperature capability and shelf life over nitrile. The meta‐aramid diaphragm fabric
demonstrates improved strength retention at elevated temperature and radiation conditions.

Instruction Manual

D100348X012

CAUTION

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

Under the 10CFR50, Appendix B, quality assurance program, the 2625NS volume booster is qualified “commercial
grade dedicated”. These can be supplied as 10CFR, Part 21 items.

Specifications

Specifications for the 2625 and 2625NS volume booster are listed in table 1. Information for an individual unit as it
comes from the factory appears on the product nameplate.

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Instruction Manual

D100348X012

Table 1. Specifications

2625 and 2625NS Volume Booster

January 2015

Port Diameters

(1)

Supply Port: J 9.5 mm (0.375 inch) or J 12.7 mm
(0.5 inch)

Operative Temperature Limits

2625: -40 to 71_C (-40 to 160_F)
2625NS: -40 to 93_C (-40 to 200_F)

Exhaust Port: J 2.4 mm (0.094 inch), J 9.5 mm

(0.375 inch) or J 12.7 mm (0.5 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

(2)

Maximum Flow Coefficients

See table 2

Connections

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

Hazardous Area Classification

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

When used in conjunction with a positioner or other
pneumatic accessory, always pipe the positioner and
booster with one common supply through a Fisher
67D, 67DR, or 95H regulator (see figure 2). A

Safety Instrumented System Classification

SIL3 capable - certified by exida Consulting LLC
high‐capacity filter, such as the Fisher 262K, should
be installed in the supply line to the regulator. Supply

Approximate Weight

pressure also must not exceed the maximum
pressure rating of the actuator. Constructions are

2.3 kg (5 pounds)

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)

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

Nominal Deadband

Percent of Positioner Output Span

(3)

(4)

:

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%

1. May be used in any combination.

2. The pressure/temperature limits in this document, and any applicable code or standard limitation should not be exceeded.

3. This term defined in ISA Standard S51.1

4. Zero psig to maximum supply.

with Sound Engineering Practice (SEP) and cannot

bear the CE marking related to PED compliance.

However, the product may bear the CE marking to

indicate compliance with other applicable EC

Directives.

(2,3)

Educational Services

For information on available courses for 2625 and 2625NS volume boosters, as well as a variety of other products,
contact:

Emerson Process Management
Educational Services - Registration
Phone: [phone] or [phone]
e‐mail: [e-mail]
http://www.emersonprocess.com/education

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2625 and 2625NS Volume Booster

January 2015

Instruction Manual

Table 2. Maximum Flow Coefficients

PORT SIZE COMBINATIONS

Supply Port Exhaust Port

mm Inch mm Inch C

9.5 0.375

12.7 0.5

FIELDVUE™ DVC6200, DVC6200 SIS, DVC6200f, DVC6200p, DVC6000, DVC6000 SIS,
DVC6000f digital valve controllers

FIELDVUE DVC2000 digital valve controller
Low Pressure Relay
High Pressure Relay

Fisher 3570 valve positioner 0.25 0.25

Fisher 3582 valve positioner 0.17 0.19

Fisher 3610J, 3610JP, 3611JP, 3620J, 3620JP, 3621JP valve positioner 0.37 0.30

2.4

9.5

12.7

2.4

9.5

12.7

0.094

0.375

0.5

0.094

0.375

0.5

SUPPLY PORT COEFFICIENTS EXHAUST PORT COEFFICIENTS

v

3.74

3.74

3.74

4.98

4.98

4.98

0.37 0.31

0.13

0.19

Installation

D100348X012

C

v

0.23

2.29

3.40

0.24

2.30

3.40

0.15

0.20

WARNING

Always wear protective clothing, gloves, and eyewear when performing any maintenance procedures to avoid personal
injury.

System damage may result if a volume booster is installed in a way that it can be physically damaged.

Personal injury or system damage may result when service conditions exceed booster or other equipment ratings.
Exceeding the pressure specifications in table 1 may cause leakage, parts damage, or personal injury due to bursting of
pressure‐containing parts or explosion of accumulated gas.

Check with your process or safety engineer for any additional measures that must be taken to protect against process
media.

Note

Do not use separate pressure supplies for the volume booster and associated positioner.

The volume booster may not exhaust immediately upon loss of a separate pressure supply. However, if the system is in a transient
state at the time of pressure supply loss or if changes to the booster's input signal are sufficient to overcome the deadband, the
booster will exhaust.

A loss of a pressure supply (either separate or common) to a 3582 or 3610J positioner will cause the positioners output pressure
(booster's input pressure) to decay.

Always pipe the positioner and the volume booster with one common supply. See figure 2 for typical installation
examples. A 67D, 67DR, or 95H regulator is required to provide sufficient capacity to supply both components. A
high‐capacity filter, such as the 262K, should be installed in the supply line to the 67D, 67DR, or 95H regulator.

Mounting

The volume booster is typically nipple‐mounted between the pneumatic supply source and the actuator, and may be
used with piston or diaphragm actuators. Many actuators require larger casing or cylinder connections and
modifications to allow the booster to deliver the higher volume output.

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