THORLABS PACU User Manual

PACU
Pure Air Circulator Unit

User Guide

Pure Air Circulator Unit

Table of Contents

Chapter 1 Warning Symbol Definitions..............................................................................................1

Chapter 2 Safety....................................................................................................................................2

Chapter 3 Description...........................................................................................................................3

3.1. Introduction ..................................................................................................................... 3

3.2. Setup Description ............................................................................................................ 3

3.3. Features ........................................................................................................................... 3

3.4. Replacement Parts .......................................................................................................... 3

Chapter 4 Setup.....................................................................................................................................4

4.1. Unpacking PACU ............................................................................................................. 4

4.2. Installing the Supply and Return Lines and Operation ............................................... 4

Chapter 5 Operation..............................................................................................................................5

Chapter 6 Maintenance.........................................................................................................................6

6.1. General Care Information ............................................................................................... 6

6.2. Filter Replacements ........................................................................................................ 6

6.2.1. Step One: Top Panel Removal ............................................................................................. 6

6.2.2. Step Two: Removal of Filters ................................................................................................ 7

Chapter 7 Specifications......................................................................................................................8

Chapter 8 Mechanical Drawing............................................................................................................9

Chapter 9 Appendix..............................................................................................................................10

9.1. Declaration of Conformance ........................................................................................ 10

Chapter 10 Regulatory...........................................................................................................................11

Chapter 11 Thorlabs Worldwide Contacts..........................................................................................12

Pure Air Circulator Unit Chapter 1: Warning Symbol Definitions

Chapter 1 Warning Symbol Definitions

Below is a list of warning symbols you may encounter in this manual or on your device.

Symbol Description

Direct Current

Alternating Current

Both Direct and Alternating Current

Earth Ground Terminal

Protective Conductor Terminal

Frame or Chassis Terminal

Equipotentiality

On (Supply)

Off (Supply)

In Position of a Bi-Stable Push Control

Out Position of a Bi-Stable Push Control

Caution: Risk of Electric Shock

Caution: Hot Surface

Caution: Risk of Danger

Warning: Laser Radiation

Rev F, October 4, 2017 Page 1

Caution: Spinning Blades May Cause Harm

Pure Air Circulator Unit Chapter 2: Safety

Chapter 2 Safety

All statements regarding safety of operation and technical data in this instruction manual will only apply when the
unit is operated correctly.

CAUTION

Please read the instruction manual carefully before operating the PACU unit. All statements regarding
safety and technical specifications will only apply when the unit is operated correctly. This equipment

is intended for laboratory use only and is not certified for medical applications, including but not

limited to life support situations.

CAUTION

Latex gloves should be worn to prevent oil from fingers from reaching all connections and fitting

surfaces.

SHOCK WARNING

Check the supply voltage of the system before plugging in the unit. Make sure the included

cord is connected to a properly grounded outlet (90 – 240 VAC; 50 – 60

SHOCK WARNING

Before removing any of the panels to gain access to the inside of PACU, disconnect AC power. Make

sure the power cable is disconnected from the unit.

Hz).

power

Page 2 TTN004825-D02

Pure Air Circulator Unit Chapter 3: Description

Chapter 3 Description

3.1. Introduction

The Pure Air Circulator Unit (PACU) is a stand-alone, closed-loop filtration system. It consists of several filters that
remove moisture and particulates. The unit is designed to operate in a closed-loop fashion. The exhaust or clean
air enters a cavity that is sealed from the external environment and exits that cavity back into the PACU. The PACU
is ideally suited for the continuous filtering and circulation of extremely clean, dry air (or nitrogen) in an optical cavity.
If the PACU is to be used in an open-loop system, the moisture trap should be monitored often, since the filter is
removing moisture from the surrounding environment.

A pump and three filters produce a continuous supply of extremely clean, dry air. An adjustable speed, micro­diaphragm, in-line pump pumps the intake air into a conglomerate of filters.

Filter 1 is filled with an indicating desiccant for the removal of moisture, impurities, and particulates from the
circulated air. Filter 2 is also an indicating type molecular sieve to absorb volatile organic compounds (VOC). Purified
air then enters the final Filter 3 to remove any particulate sized greater than 15 um. This filter traps fine particles in
a dense matrix of a sintered element. This sintered metal filter’s elements are manufactured from stainless steel
powders via a powder metallurgy process.

In typical closed-loop operation, clean air is filtered into a closed cavity and then pulled back into the circulator to
be processed again to remove any additional moisture or particulates. It may be used in open-loop operation, the
indicating desiccant should be monitored and replaced if saturation has occurred.

3.2. Setup Description

The Thorlabs PACU Pure Air Circulator Unit is a self-contained unit that may operate as a tabletop unit or may be
rack mounted in a standard 19-inch rack cabinet. Access to the intake and supply line must be available. If the unit
is to be used in on a tabletop, then the rack ears and handles may be removed.

 We recommend that the supply line tubing be a good-quality, low outgassing type, such as

fluoropolymer. This kind of semi-flexible tube maintains high integrity with less cross- contamination. We
use 3/16" ID x 1/4" OD x 3/32" wall, 266 PSI Chemfluor 367 Tubing throughout the unit.

 Because the unit is self-contained, it is only necessary to connect the 1/4” tubing to the device that needs

to be purged with clean air.

 The user should consider where the pure air will enter the unit and where the exhaust air will be drawn out

of the unit. Best results are achieved if the intake and exhaust are in the same plane, but this is not
absolutely necessary.

 If the unit is in open-loop mode, or the volume to be purged is exposed to external air (moisture), then

periodic checks on the indicating desiccant are necessary.

 The system uses a switchable power supply capable of 110 – 230 VAC, 50 – 60 Hz (90 – 264 VAC,47 –

440 Hz max rating).For support or more info, please contact [e-mail].

3.3. Features

 Closed-Loop Air or Nitrogen Filtration System


Adjustable Air Flow by Pump Speed

 Sight-Gauged Air Flow Meter
 1/4"Quick-Connect Hose Connections

3.4. Replacement Parts

 Filter 1 – Desiccant Filter (PACU-FTR1)


Filter 2 and 3 (sold together) – In-Line

 Tubing - 3/16" ID x 1/4" OD x 3/32" wall, 266 PSI, Chemfluor® 367 Tubing

Rev F, October 4, 2017 Page 3

15 µm filter

and Molecular Sieve (Part Number PACU-FTR3)

Pure Air Circulator Unit Chapter 4: Setup

Chapter 4 Setup

The PACU pure air circulator unit is self-contained. 1/4” supply and return hoses are not included.

4.1. Unpacking PACU

1. Remove the unit, including the AC power cord, from its shipping container.

a. If the unit is to be used in a 19” rack mount chassis, use four 10-32 rack screws.

b. If the unit is to be used on a tabletop, and the rack ears and handles may be removed from the

unit.

2. The unit is configured to operate at 110 – 230 VAC, 50 – 60 Hz. Simply connect a power cord
appropriate for your geographic region. The unit includes a U.S. power cord. If you need a different plug,
please contact [e-mail].

4.2. Installing the Supply and Return Lines and Operation

SHOCK WARNING

Check the supply voltage of the system before plugging in the unit. Make sure the included power

cord is connected to a properly grounded outlet (90 – 240 VAC; 50 – 60 Hz).

 The unit is designed for 1/4" tubing. We recommend type 3/16" ID x 1/4" OD x 3/32" wall, 266 PSI

Chemfluor® 367 Tubing. Chemfluor® 367, a unique fluoropolymer, maintains fluid integrity and in many
ways outperforms tubing made from standard, and even high-purity, PFA resin.

The surface is up to six times smoother than tubing made of standard and high-purity resin. This results in
less cross-contamination, greater productivity yields, and easier-to-clean systems.

This tubing can be used in virtually any application where maintaining high purity is critical, such as the
semiconductor, pharmaceutical, laboratory, environmental, or food processing industries. The operating
temperature ranges from -320 °F to 450 °F.

 The unit operates most efficiently when providing clean air to a sealed enclosure with an air intake and an

air exhaust. This maintains the integrity of the desiccant for longevity. The desiccant is moisture-indicating
and is situated in a transparent filter container for inspection.

 Once the supply lines have been installed, the unit may be turned on. A control knob regulates the

diaphragm pump speed. By increasing the speed, the amount of air flow will be increased. A flow meter
gauge measures air flow rates from 0 to 5 L/min. Clean air is supplied almost immediately after power on.



For optimal particle and moisture removal, the PACU should operate at a flow rate of 3 L/min.



A digital clock on the front panel keeps track of how long the unit has been powered up.

Page 4 TTN004825-D02

Pure Air Circulator Unit Chapter 5: Operation

Chapter 5 Operation

! !

Please read the instruction manual carefully before operating the PACU unit. All statements regarding
safety and technical specifications will only apply when the unit is operated correctly. This equipment

is intended for laboratory use only and is not certified for medical applications, including but not

limited to life support situations.

The flow rate of the Viton membrane pump is continuously adjustable by a knob on the front panel and is measured
by an in-line flow meter immediately before the output. A series of vent holes is provided on top of the housing,
which makes it possible for the user to see if satuaration has occured in the desiccant without dismantling the unit.
Pink desiccant indicates that the desiccant is saturated and should be replaced. An elapsed time counter on the
front indicates how long the unit has been in service. For instructions on how to replace the desiccant filter, please
see section 6.2. During standard operation it is recommended that the air flow meter is checked in regular intervals.

CAUTION

Rev F, October 4, 2017 Page 5

Pure Air Circulator Unit Chapter 6: Maintenance

Chapter 6 Maintenance

6.1. General Care Information

The desiccant filter that removes the moisture requires the most attention. The filter contains blue, indicating
desiccant. When indicating desiccant turns pink, the desiccant needs to be changed. Filter 1 and 2 may be inspected
through the vent holes in the top panel of the PACU unit.

Both Filters 1 and 2 are indicating when saturated and can easily be inspected for changing by their indicating color
change to pink. Filter 2 and Filter 3 should be changed together. The time period between filter changes depends
upon the chamber that is being filtered. When the unit is new, the flow meter typically peaks as the maximum pump
speed is approached. Should the filters be saturated, a reduced amount of air flow will show on the flow meter. We
have run the unit for hundreds of hours with no degradation of flow or increase in particle count. If it is deemed
necessary to change the particulate filters, they should be changed simultaneously.

6.2. Filter Replacements

Thorlabs uses indicating desiccant in the Pure Air Circulator Unit Filter 1, which changes color from blue to pink
when the desiccant is saturated with water. Filter 2 also uses a blue indicating material that will change its color to
pink when saturated. If either filter shows signs of saturation please replace them. The vent holes located on the
top panel of the PACU system offer a convenient way to check for saturation without having to disassemble the
unit. When used in a closed-loop system, the particulate filters used in the PACU should greatly outlast the
desiccant. Replace the particulate filter when you notice a decrease in flow rate at a given pump speed. The
instructions below describe the necessary steps to replace any of the three filters.

Thorlabs supplies replacement filters online at www.Thorlabs.com.

Phillips Head Screwdriver

Required Tools:

Flat Head Screwdriver
9/16” Wrench (Not Socketed) or Adjustable Wrench
Teflon Tape

6.2.1. Step One: Top Panel Removal

SHOCK WARNING

Before removing any of the panels to gain access to the inside of PACU disconnect AC power.

Make sure the power cable is disconnected from the unit.

To remove the top panel of the PACU system, use a Phillips head screwdriver to remove the four screws located
in the four corners of the panel (as shown in Figure 1).

Figure 1 Screw Locations

After all four screws have been removed; the top panel can be removed by sliding the top panel towards the back
of the system which will free the opposite side to be gently lifted. If you find it diffic u l t to slide the to p p a nel

Page 6 TTN004825-D02

Figure 2 Removing Panel

Pure Air Circulator Unit Chapter 6: Maintenance

back, you may need to slightly loosen the two screws on the tops of the side panels. Once lifted the
top panel can be pulled out (as shown in Figure 2).

6.2.2. Step Two: Removal of Filters

!

Latex gloves should be worn to prevent oil from fingers from reaching all connections and fitting

Once the top panel has been removed, you will have direct access to all three filters within the PACU system.
Before any filters can be removed, you must disconnect all hoses from filters 1 and 2 by loosening the hose clamp
connections. Do not remove the brass couplers. Loosening the clamp allows disconnection from the barbed filter
entrance and exit. Once both filters are disconnected they may be removed from the holding clamps. To remove
Filter 3, a flat head screwdriver and a 9/16” wrench or adjustable wrench is needed. The filter clamp holds Filter 3
in place and a Swagelok connection secures the tubing. Once all connections have been disconnected you may
remove that filter and replace it. Replacement filters can be purchased online at www.Thorlabs.com.

CAUTION

surfaces.

!

Figure 3 The red arrows indication locations where the indicating dessicant filter is connected to

the PACU System via hose clamps. Loosen the hose clamps and slide the tubing from the plastic

barb of the filter housing. Do not remove the brass couplers.

Figure 4 The red arrows indicate locations where the indicating particulate filter is connected to the

PACU System via hose clamps. Loosen the hose clamps and slide the tubing from the plastic barb

of the filter housing. Do not remove the brass couplers.

Rev F, October 4, 2017 Page 7

Pure Air Circulator Unit Chapter 7: Specifications

Chapter 7 Specifications

Flow Rate1 0.6 to 4.5 L/min
Flow Meter Range
Filters
Moisture Trap

2

(Desiccant)

Particulate Filters

Air Pump

Internal Tubing

External Tube Fittings

Power Compatibility

Dimensions (L x W x H)
Weight

Performance Specifications

0.6 to 5 L/min

1.25 lbs (0.6 kg) Desiccant

15 µm, Sintered Pore Element Filter

13X Molecular Sieve, 1.1 lbs (0.5 kg)

Micro-Diaphragm Pump with 4.5 L/min Max Delivery

Chemfluor

Type 316 Stainless Steel, Chemical-Resistant PVDF

110 - 230 VAC, 50 - 60 Hz Operation, Location

19.0" x 13.0" x 7.0" (483 mm x 330 mm x 178 mm)

®

367 Fluoropolymer Tubing, 3/16" ID x 1/4"

OD x 3/32" Wall, 266 PSI

®

Swagelok

Tube Fittings for 1/4" OD Tubing

Specific Power Cord Included

6.8 kg

1

The maximum value of 4.5 L/min occurs when the intake and exhaust are short circuited, i.e. directly connected.

2

Moisture Trap Capacity: 50 g

Page 8 TTN004825-D02

Pure Air Circulator Unit Chapter 8: Mechanical Drawing

Chapter 8 Mechanical Drawing

Rev F, October 4, 2017 Page 9

Pure Air Circulator Unit Chapter 9: Appendix

Chapter 9 Appendix

9.1. Declaration of Conformance

Page 10 TTN004825-D02

Pure Air Circulator Unit Chapter 10: Regulatory

Chapter 10 Regulatory

As required by the WEEE (Waste Electrical and Electronic Equipment Directive) of the European Community and
the corresponding national laws, Thorlabs offers all end users in the EC the possibility to return “end of life” units
without incurring disposal charges.

 This offer is valid for Thorlabs electrical and electronic equipment:
 Sold after August 13, 2005
 Marked correspondingly with the crossed out “wheelie bin” logo (see right)
 Sold to a company or institute within the EC
 Currently owned by a company or institute within the EC
 Still complete, not disassembled and not contaminated

As the WEEE directive applies to self-contained operational electrical and electronic products, this end of life take
back service does not refer to other Thorlabs products, such as:

 Pure OEM products, that means assemblies to be built into a unit by the user (e. g. OEM laser driver cards)
 Components
 Mechanics and optics
 Left over parts of units disassembled by the user (PCB’s, housings etc.).

If you wish to return a Thorlabs unit for waste recovery, please contact Thorlabs or your nearest dealer for further
information.

Wheelie Bin Logo

Waste Treatment is Your Own Responsibility

If you do not return an “end of life” unit to Thorlabs, you must hand it to a company specialized in waste recovery.
Do not dispose of the unit in a litter bin or at a public waste disposal site.

Ecological Background

It is well known that WEEE pollutes the environment by releasing toxic products during decomposition. The aim of
the European RoHS directive is to reduce the content of toxic substances in electronic products in the future.

The intent of the WEEE directive is to enforce the recycling of WEEE. A controlled recycling of end of life products
will thereby avoid negative impacts on the environment.

Rev F, October 4, 2017 Page 11

Pure Air Circulator Unit Cha

Chapter 1 Thorlabs Worldwide Contacts

pter 11: Thorlabs Worldwide Contacts

USA, Canada, and South America

Thorlabs, Inc.
56 Sparta Avenue
Newton, NJ 07860
USA
Tel: [phone]
Fax: [phone]
www.thorlabs.com
www.thorlabs.us (West Coast)
Email: [e-mail]
Support: [e-mail]

Europe

Thorlabs GmbH
Hans-Böckler-Str. 6
85221 Dachau / Munich
Germany
Tel: [phone]
Fax: [phone]
www.thorlabs.de
Email: [e-mail]

France

Thorlabs SAS
109, rue des Côtes
78600 Maisons-Laffitte
France
Tel: [phone]
Fax: [phone]
www.thorlabs.com
Email: [e-mail]

Japan

Thorlabs Japan, Inc.
3-6-3 Kitamachi,
Nerima-ku, Tokyo 179-0081
Japan
Tel: [phone]
Fax: [phone]
www.thorlabs.co.jp
Email: [e-mail]

UK and Ireland

Thorlabs Ltd.
1 Saint Thomas Place
Ely CB7 4EX
Great Britain
Tel: [phone]
Fax: [phone]
www.thorlabs.com
Email: [e-mail]
Support: [e-mail]

Scandinavia

Thorlabs Sweden AB
Bergfotsgatan 7
431 35 Mölndal
Sweden
Tel: [phone]
Fax: [phone]
www.thorlabs.com
Email: [e-mail]

Brazil
Thorlabs Vendas de Fotônicos Ltda.
Rua Riachuelo, 171
São Carlos, SP 13560-110
Brazil
Tel: [phone]
Fax: [phone]
www.thorlabs.com
Email: [e-mail]

China
Thorlabs China
Room A101, No. 100, Lane 2891,
South Qilianshan Road
Putuo District
Shanghai 200331
China
Tel: [phone]
Fax: [phone]
www.thorlabschina.cn
Email: [e-mail]

Page 12 TTN004825-D02

www.thorlabs.com